Trident autothrust system and autoland [Archive]

Trident Sim

22nd Nov 2010, 00:49

How surprising, and rather pleasant, that some level of interest in the Trident still exists!

Did the No 2 engine have a significant pitch couple?

No, not really; certainly not when compared to other, later, aircraft in BA’s fleet. A cynic might say that one needed significant thrust changes to cause a significant pitch change! ;)

My (hazy) recollection is that number 2 was actually not connected to the autothrottle

That is correct - although it could be if required. It was checked OUT during the pre-take off setting up of the FCS and Radios, and I can't remember No 2 A/T switch ever being engaged thereafter.

Had to keep number 2 at a medium thrust level (10,800 N1 or N2 maybe? - too long ago to remember)

Well remembered! I’ve still got the manuals and so was able to look the figures up:

T1: 10,800
T2: 11,000
T3: 11,200

It’s now nearly 30 years since I last flew the “Gripper”, but IIRC A/T was ONLY used for autoland

I would respectfully disagree, as my recollection is that A/T was used a lot, perhaps even a majority of the time, on all approaches, during the early days of the Trident fleet, as many a passenger who had the misfortune to sit down the back of the aircraft could probably testify to! The constantly varying noise levels from the engines, as they continually spooled up and down, was appalling!

In the early seventies, many (but not all) older Captains, who had come to the Trident from propeller driven aircraft, were very reluctant to allow manual throttle handling on approach. For those that would permit it, as O & H has already mentioned, it was their hands on the throttles, not yours, a procedure I still think odd!

I seem to remember that it was only after a significant number of Trident F/Os had returned to the fleet as Captains that a more enlightened and sensible approach to throttle handling became prevalent. By the time I flew the T3 in the eighties, manual throttle approaches were very common, and the reduction in noise nuisance, both on the ground and in the cabin, was substantial.

Jo90

22nd Nov 2010, 13:57

The reason why NHP handled the throttles on approach is that the throttles were so far forward that you could not properly reach them when fully open without leaning forward. This would hardly aid accurate flying.
Just one of the 'gripper's' many design failings.

petitb

22nd Nov 2010, 17:47

Many years ago, both the VC10 and Trident had "noisy" autothrottles. At Wisley Flight Test on the VC10 we considerably improved matters by moving the pitot heads further out from the fuselage and out of the boundary layer. As a result of friendly relations between a couple of individuals, we (the VC10 lot) gave the idea for the mod to Hatfield Flight Test free (well, let's say a pint or two) and gratis. Just thought you might like to know this.
Also, you might like to discuss engaging reverse thrust on the Trident before touchdown.

Old and Horrified

22nd Nov 2010, 19:09

Ahh - I had forgotten about that. You could actually use reverse at any altitude and so, with full airbrake as well, and despite residual power on number 2 engine, achieve huge rates of descent. The use of reverse in the flair was recommended for very short runways as the brakes were not great. I remember Edinburgh before it got extended and Gibraltar, but, as these were always Captain's landings I never did try it myself. I also happen to know that it often frighten the passengers at the back!

Crosswind Limits

22nd Nov 2010, 19:18

You just couldn't make this stuff up could you!? :p Using thrust reverse at altitude and in the flare!!!!! :ooh: :p

Why was the Trident called the "gripper"? Anything to do with pilots "gripping" the controls in case the autoland system failed or did something unexpected??

WHBM

22nd Nov 2010, 19:46

You just couldn't make this stuff up could you!? :p Using thrust reverse at altitude and in the flare!!!!! Tupolev 154 pinched the idea (maybe the pinched the entire set of blueprints) and have used this for the last 40 years. Plenty of photographs around of doing it.

Why was the Trident called the "gripper"? Anything to do with pilots "gripping" the controls in case the autoland system failed or did something unexpected??Allegedly it "Gripped" the ground on takeoff. However, having made more than one departure in those rearward-facing seats it had in the cabin, and felt on rotation that I was nearly falling vertically into the laps of those I was facing (usually the boss) were it not for the seatbelt, I never quite went along with this one.

Bilgediver

22nd Nov 2010, 19:49

Quote:

I remember Edinburgh before it got extended and Gibraltar, but, as these were always Captain's landings I never did try it myself. I also happen to know that it often frighten the passengers at the back!

We got used to it at Edinburgh and Aberdeen in those early oilfield days. Gave the SLF something to talk about over a pint in the SKean Dhu. Carrier Deck landings! :p

WHBM

22nd Nov 2010, 20:31

Trident into Edinburgh :

I recall that the Edinburgh route stayed with the Vanguard until the end of its service, because BA said the old runway was too short, and the wrong orientation for the prevailing wind, to use for Trident operations. This was a significant part of the discussions in the mid-1970s about the new runway.

Once the new runway was approved, it seemed the Vanguards steadily disappeared, and the route became 100% Trident quite some time before the new runway was commissioned (1977 ?).

Meikleour

23rd Nov 2010, 10:19

WHBM: The Trident did do flights into Edinburgh in the early `70`s but I seem to recall that these stopped after a particular Trident slightly overrun the end of 31 into the fence by the Falkirk road. Strong crosswinds at Edinburgh were a problem also for the Vanguard since you could not select Ground Fine until BOTH mainwheels were on the deck and sometimes that was difficult to achieve and so go-arounds off the runway were not unheard of! Still the passengers down the back got a fine view of the runway on approach due to the large drift angle!

blind pew

23rd Nov 2010, 11:18

The early Trident ones spawned the name "Ground Gripper" as it couldn't take off from Heathrow on a hot summer's day at Max take off weight - it was eventually re engined.
It did go into the old Edinburgh but one ran off the end.

SOP stated that engine 2 had to be left at 10800 even with engines 1 and 2 in reverse in descent although we had a character "batman" who would throttle engine 2 back until the cabin surged during descent into Gib.
He forgot to increase eng 2 rpm when he cancelled the reverse - voila another cabin surge.
He also managed to catch the cabin up with the result at around 3 grand, the dump valve opened and the cabin descended at 1500 fpm - guess the pax loved us!

Manual throttle was not permitted on 3 engines on approach but was compulsory with an engine out!

The most frightening aspect was the short field landing technique, 50 ft throttles off and select white knuckle reverse.

A mate came to a stop with the cockpit hanging over the sea wall in GIB - he was comatose and the skipper pealed his hands off the throttles and cancelled the reverse.

It was the most difficult kite that I flew (six different jets)- min drag was around 225 knots and we approached at approx 135 knots - faster than a lot of other ships which gave problems for ATC with spacing on approach.

I think the NHP operating the throttles came about as a few of the ex bomber command boys found it very difficult to hand fly.
The had all arrived via straight wing piston propellor aircraft.

We did has some excellent older guys but there were a few who thought that the a/p was minimum equipment.

It is probably how the monitored approach system came about.

It changed after with the ex meatbox/hunter and hamble guys arrived in the LHS.

The worst part was dead heading into Glasgow during the winter - scottish ATC wouldn't/couldn't talk to the southern ATC so it was always a dirty dive with reverse/airbrakes and ant icing whilst pointing an mountainous terrain.

The T2 also had a trick where you could drop the main undercarriage (gear in american) at VNE but someone forgot to reset the switch and ex LHR the crew returned as they couldn't raise it.

It was extremely fast and the best fun was racing the Swiss Coronados into heathrow - beat them a couple of times although never managed it into ZRH.

Happy memories!

suninmyeyes

23rd Nov 2010, 11:21

Her's one to tickle the memory cells.

I seem to remember some Tridents had 2 yaw dampers some had 3. On some versions you could go with one inoperative. I can't remember which way round.

Bergerie1

23rd Nov 2010, 11:30

Thank God, I never flew Ground Grippers. Iron Ducks were much better!

blind pew

23rd Nov 2010, 20:46

Couldn't agree more, loved the iron duck.

Missed one unique gripper feature - the undercarriage oleos had an extremely small movement - supposedly as it was believed that with a normal range of movement that the computers wouldn't be capable of performing an autoland.

There were a few brave souls who had a special landing technique - late flare and at the last moment stuff the stick fwd.

It worked wonders and used the technique later on the DC9-51 which was also difficult to grease on at 300M with a normal flare.(the earlier 9s weren't a problem).

If you manage to get hold of a copy of the corporations recruiting film made in the mid 60s you will see both the Gripper and the Duck.

Most entertaining - and enlightening-but showed a typical trident controlled crash.
It is available through the Hamble web site!

Prober

23rd Nov 2010, 22:38

Indeed, one does forget! Yes, of course the A/T was used for most approaches as well as A/Land - not as I said earlier. Yes, there was a switch somewhere in the ceiling for engaging No2, but this was, to my knowledge, never used. And reverse was selected at the flair for all landings so far as I recall, with the final few seconds spent floating on a cushion of air. The main gear as an airbrake switch actually disconnected the nose wheel deployment and the incident mentioned suffered a "nose wheel fails to lower" when it came to the actual landing. The switch was then disconnected! I remember more difficulty at Gib on the Vanguard rather than the Trident, with the fire service knocking on the window at the end of one white knuckle arrival! The worst of that airfield was the (RAF) controllers telling you that you had just violated the other side's airspace, rather than telling you that you were about to and you could then have done something about it. Hey Ho! As to EDI, T1 and T2 ops were usually uneventful (on 13/31). The arrival of the T3 caused tire bursts on a regular basis, and the previously mentioned method of touchdown (nose forward), was developed by some intrepid pilots and it worked very well, but trg establishment would rap our knuckles. It was a delight to fly and I enjoyed most of my 7,000 odd hours both as P1 and P2/3.
Prober

twochai

24th Nov 2010, 03:08

I never flew Ground Grippers. Iron Ducks were much better

Ok, Ok, I know the Gripper, but what's an 'Iron Duck' and why??

Old Fella

24th Nov 2010, 04:12

Sure, the BAC 1-11 used only two Speys against the Tridents three, but it only weighed about two thirds the weight of the Trident 3 at MTOW.

DozyWannabe

24th Nov 2010, 13:49

You just couldn't make this stuff up could you!? :p Using thrust reverse at altitude and in the flare!!!!! :ooh: :p

You could do it on many aircraft of the era.

The reason why NHP handled the throttles on approach is that the throttles were so far forward that you could not properly reach them when fully open without leaning forward. This would hardly aid accurate flying.
Just one of the 'gripper's' many design failings.

Ergonomics weren't a big thing on any airliner back then, no matter who made them! Early 707s were famous for having slightly different cockpit layouts depending on the customer.

Technologically speaking the Trident was probably the most advanced airliner in service at the time it was launched - most of the compromises that hobbled it were in fact demanded by BEA. This is borne out by the fact that Boeing took the original specification and design (minus the advanced avionics) and copied it almost verbatim in the form of the 727, which went on to become the best-selling aircraft in the world, holding the record for nearly two decades.

Sure, the BAC 1-11 used only two Speys against the Tridents three, but it only weighed about two thirds the weight of the Trident 3 at MTOW.

If only BEA hadn't meddled and Trident got the RR Medway engine originally specifed...

WHBM

24th Nov 2010, 14:30

This is borne out by the fact that Boeing took the original specification and design (minus the advanced avionics) and copied it almost verbatim in the form of the 727
Ths is a long-standing comment, but I wonder how accurate it is, apart from the basic aircraft configuration. The 727 front end and fuselage were taken directly from the 707 (and the 737 still is). Is the DC8 also a 707 copy, because it was the same configuration ?

As I understand it, although the first Trident design had more substantial engines, it didn't have the high-lift devices of the 727 which lifted the first 727s off short runways because it was intended (by BEA) to operate from Heathrow to other major European airports, most of which were already handling 707s etc, whereas the 727 sold initially to US airlines to operate into many places where the DC6 was the biggest they had seen up to then. I doubt either Trident version could have operated out of the 6,000 foot runways that La Guardia had when the 727 came into service.

The first generation of "smaller" jets, 2 and 3 engined (of which the pioneer was the Caravelle), all went for rear-end, fuselage-mounted engnes, because that was more straightforward to control with an engine out, plus they were concerned about sucking up FOD on lesser runways. Only when the 737 came along had the research been fully done on how to handle wing-mounted engines. This configuration then came back into vogue more recently when all the the RJs came along, for different reasons which we need not dilute this discussion of the Trident era with.

Bergerie1

24th Nov 2010, 14:47

twochai

The Iron Duck was the magnificent Vickers VC10. Our irreverent colleagues on 707s used to call it that because much of the structure was milled out of the solid - alumnium not iron! I spent many happy years flying VC10s.

DozyWannabe

24th Nov 2010, 14:58

Ths is a long-standing comment, but I wonder how accurate it is, apart from the basic aircraft configuration. The 727 front end and fuselage were taken directly from the 707 (and the 737 still is). Is the DC8 also a 707 copy, because it was the same configuration ?
Interesting article here - no proof of course, but it does seem an odd coincidence:

British Airliners 'Nearly Get It Right' Shock! - Aircraft of World War II - Warbird Forums (http://www.ww2aircraft.net/forum/post-war/british-airliners-nearly-get-right-shock-17298.html)

You're right in that the Trident didn't have the same high-lift devices as the 727, but the first generation's droop and flap configuration was still pretty potent. It needed to be, because the wing was designed for high-speed cruise (I have it on good authority that despite being a bugger to get off the ground, the Gripper went like a scalded cat in cruise). Re-use of the 707's nose and fuselage section would always have been a no-brainer for Boeing, because they already had all the jigs and tooling in place.

While you're also right about the Caravelle, the Trident was the first design to use a triple engine configuration with an S-duct on number 2, which is the primary similarity with the 727. Had it had the Medway engine as specified, I don't think it would have found a 6,000 ft runway a problem. Purely speculation though. :)

dixi188

24th Nov 2010, 15:41

IIRC the title sequence for the BBC series "Softly Softly Task Force" showed a BEA trident landing at GIB and you could see the reverse thrust smoke from the cascades before touchdown.

slast

25th Nov 2010, 13:23

Prober, "The main gear as an airbrake switch actually disconnected the nose wheel deployment and the incident mentioned suffered a "nose wheel fails to lower" when it came to the actual landing. The switch was then disconnected!!" ...... not quite the full story......... "I was that man"!! (Also can you point me to the post with the "incident mentioned").

We were doing LHR-GVA-LHR in about 1967 (EDIT: 16 December 1966) in a Trident 1 (EDIT: GARPM) , with a Very Senior Management Pilot (VSMP) in the LHS making his once a month recency flight, and as I recall he flew the approach. I was the junior F/O with one ring I think. Can't remember the SFO in the RHS at the moment (EDIT: SFO Chris Cross) and my logbooks aren't to hand. Strong NW tailwind and held up very high by French ATC all the way to the then Swiss border, as was their habit, before getting clearance to descend from GVA control. Anyway the very late TOD meant using everything to get down expeditiously approaching.

IIRC the layout was that the airbrake lever was on the left side of the console, and just to one side and behind its stowed position was a toggle switch which enabled you to drop the main gear only, as you said, at a max. speed of 320 kts (?) IAS. Alongside the switch was an amber warning light to tell you you'd used it. Retraction was limited to 280 (?) though.

VSMP deployed airbrake lever and then main gear while decelerating, cleaning up as the speed decreased and we got round and landed with no problems.

We turned around and took off again, and on selecting gear up the main wheels stayed firmly down: 2 reds and 2 greens. The main gear had an emergency free fall that was activated via a hatch in the centre cabin floor that actually opened into the cargo hold, and accessed a lever for a compressed air bottle that would blow the gear down.

VSMP says there has been an incident elsewhere on the network where a loader in the hold has grabbed this lever and discharged the bottle, causing the main gear to refuse to retract. Therefore that is what has happened. Declares an immediate return to GVA and we went back and landed. VSMP departs cockpit to investigate and deliver bollocking to ground staff.

SFO and I are discussing this in this his absence and doing the turnround checklist when we notice main gear airbrake switch is still in "extended" position although the warning light is out.

VSMP returns and red faces ensue. SFO and I got an informal bollocking from chief pilot for not being smart enough to know that VSMP needed watching like a hawk! and "lessons are duly learned".

Meanwhile VSMP takes up subject of failed warning lamps etc. with manufacturer (de Haviland). It transpired that on every other aircraft on the fleet there was a striker pin on the airbrake lever, such that when the airbrake was stowed after use, it would also return the "main gear airbrake" switch to the "up" position, if it hadn't already been done. It wasn't installed on this aircraft! More significantly, they were horrified to find that we were using this facility on a relatively routine basis, as it was only intended as an emergency facility for rapid decompressions etc. Hence came the removal of the ability to use it - I can't even remember if it was even actually installed on the T2 and T3.

Happy days!
Steve

blind pew

26th Nov 2010, 10:20

As pointed out Vickers built the VC10 and supposedly used ship building techniques - I was told that the Iron duck came from the substantial titanium brackets that held the donks on!

Trident gear/airbrake limits. Lower retraction speed was if the grey matter is correct - due to the nose gear doors ( undercart was off set with one large door).
The main gear airbrake was still in use in 1972 when I come onto the gripper - I believe there was yet another incident at lhr before the function was inhibited.

Cruise speed - yes it was very fast but MMO had been reduced (think it was originally M.92)
It went very fast on one special flight with a couple of Very senior management extremely competent pilots (if you believed them) who,if P3 is to believed, pulled the CB and flew at M.design as tghe young lady down the back was late.
I think most of us heard about it as P3 made a point of telling all and sundry.

twistedenginestarter

26th Nov 2010, 18:26

Can you expand on this idea of controlling noise? I can only think you are saying the centre engine was disconnected to cut down the noise when the autothrottle applied full power. This would suggest it was inclined to command wide power excursions. Was this an accepted shortcoming? Did leaving the centre engine at a fixed power mean the aircraft took longer to regain the glidepath?

slast

26th Nov 2010, 18:47

I think it was to reduce the degree of noise changes inside the rear cabin - as the centre engine was in the rear fuselage it was pretty noticeable.

Prober

26th Nov 2010, 21:34

Marvellous after all these years to hear from the horse's mouth. Unlike Chinese Whispers, the story actually did not get too twisted in the telling, but it is wonderful to hear what actually happened. Thanks, Steve for that.
Fast? Yes it was. Normal cruise was M.88 (on the T1). (I recall a charter from SNN to VIE in which we managed an average of 660 kts G/S - but not quite the same on the way back!) M.92 was the max during base training and recovery from that proved just as frightening an experience as deploying airbrake on the T7 Hunter at M1.1, or landing an Auster on a carrier. The T2 was .8 for no other reason than IIRC wear and tear. Then came the 1974 fuel crisis which, apart from producing the national speed limit of 70 mph (it was nothing to do with road safety), made everyone thing seriously about fuel. Up till then, fuel was not much more than an incidental in one's costings and consequently the cruise speed for all Tridents was reduced to M.8 or maybe .78 (I cannot remember).
As to noise, the Gripper was far preferable to the B1-11 with A/T engaged. The 1-11 had to do it all with 2 engines whilst the Gripper had the modifying influence of the steady No 2. Positioning on the 1-11 was not a pleasant experience, especially down the back.
Prober (Mike)

spekesoftly

26th Nov 2010, 22:20

Then came the 1974 fuel crisis which, apart from producing the national speed limit of 70 mph (it was nothing to do with road safety)

The 70mph national speed limit was first introduced as a temporary measure in 1965, and made permanent in 1967. The 1974 fuel crisis lead to a 60mph limit on dual carriageways, and 50mph on all other roads except motorways, where the 70mph limit still applied.

Anyway, please forgive the digression, and many thanks for all the Trident stuff.

Micky

26th Nov 2010, 22:35

corporations recruiting film made in the mid 60s you will see both the Gripper and the Duck.

v7RMlluY0sA
C6ilhtHLqOI
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Do you mean this film?

You can at one point clearly see the Throttle's 1&3 moving with 2 being in the roughly 12 o'clock position.
Wanted to post the same question about the auto throttle when I first saw these movies, but forgot.
Thank you everybody for the great stories...Really like the trident:ok:

Good night

Micky

Ps Really like the kick off drift writing in the RA...

lederhosen

27th Nov 2010, 06:18

slast

27th Nov 2010, 07:56

Hi Prober,
I'll have to dig out the old logbook I guess, Blindpew says we were still using main gear airbrake in '72 so it looks like I may have compressed the timescale from our event to it eventually being removed as a facility. As a junior F/O I wasn't privy to any of the management discussions! I seem to remember it was Peter Harper, with whom I later worked a lot on BALPA's technical committee, who said DH weren't happy about it, but it's a bit hazy in the mists of time!!

Prober

27th Nov 2010, 21:59

All this reminiscing brings another snippet to mind. As F/O I went to FBU with Capt Ormonroyd (Snr) who was one of the A/Land boffins and aces. FBU closed, so we had to go to Gardemoen which, in those days, was a minor satellite, semi mil, used for diversions (by BEA). We were given an NDB Approach and Capt O said that now we had a chance to prove the A/Land system. We two minions looked at each other slightly aghast, but Capt O just asked us to cast our minds back to how the system worked. All very well for him - he was a semi boffin - but we were mystified. "Remember", he said "at 133ft the aircraft system disengages from the ILS and flies the final bit on memory. We will fly a steady approach and fool it into thinking it was doing an ILS!"
We held our breath and after touchdown (hands off - nearly) I swear he smirked.

ArmyAir

27th Nov 2010, 23:47

From the Trident comments - does anyone remember Capt Jimmy Green c 1967 (ish) a BEA Captain?

G G

Landroger

28th Nov 2010, 10:56

What a great fim! I love the bit with the test pilot nonchalantly talking to the camera over his shoulder as the aircraft descends through two hundred feet. Talk about confidence in the autoland system.

Forty years later I am not sure how much things have improved. I certainly would not feel comfortable doing that on my 737....not after the autopilots tripped out in the flare a few weeks ago! Certainly got my attention.

As an SLF 'Flight Deck Groupie', when such things were possible :sad: I remember a 1983 Autoland approach to (I think) 10R at LHR in a BA 737 ex Moscow. We could see aircraft on approach disappearing into the clag from about overhead Beaconsfield VOR and all innocent, I asked if we would doing an autoland?

The reply was that they wouldn't, ordinarily, do one because they would probably break out at 1000ft and land mandraulically, but since I'd asked and they hadn't done one in a few weeks ...... :eek:

It was fascinating and just like the first film clip. The FO sat with his hands on his knees, watching and the Captain was turned round chatting to me! Mind you, just before touch down they both said "Ohhh no!" and there was a hell of a bang on landing. Stuff fell out of the rack behind me and I was clearing it off the centre console as we braked. :rolleyes: Obviously I asked ......

Apparently the Trident and BAC111 had their A/L set up to do 'greasers' on the long runways of Europe, but Boeing set up theirs to trip the WOW switches "on the zebra stripes". Obviously so the 737 can land in foul weather at indifferent airfields in Battle Creek, Michigan without falling off the runway. :rolleyes: A very interesting evening that. :D And if you are still reading; thanks to those two and all the other crews who put up with me in dozens of cockpits around the world. :)

Roger.

lederhosen

28th Nov 2010, 14:07

We have to do one a month for currency plus the real ones so over the years I have probably done a couple of hundred on the 737. Actually I don't think it does a bad job, not noticeably worse than us anyway. :}

I do not believe it is set up to make a dirty dive for the beginning of the runway, however good a story that might be. It follows the glideslope which as a cursory scan of the Jepp chart shows can lead to a quite different point. It also doesn't call you a retard in the flare, a pleasure I am soon to enjoy.

However if you do a practice autoland for currency purposes unprotected (e.g. low vis procedures not in force) there seems to be a marked tendency on our early NGs for the autopilots to trip out when the previous aircraft clears the runway.

I am fascinated by Prober's story of trying to autoland off a non precision approach. The concept of the aircraft flying based on memory seems to have been resurrected in part on our newer aircraft which are more tolerant of minor beam deviations. So again there is not much new under the sun. However the rest of it (and the earlier VSP anecdote) reinforces why some pilots get into management and maybe should stay there.

Escape Path

28th Nov 2010, 15:32

but Boeing set up theirs to trip the WOW switches "on the zebra stripes". Obviously so the 737 can land in foul weather at indifferent airfields in Battle Creek, Michigan without falling off the runway.

Pretty much.

I remember one of my instructors talking about auto-land. He said: "The autopilot doesn't care for a greaser. Its job is to put the airplane in the TDZ, sometimes it pulls a greaser but when the conditions are appropriate it comes out quite a smack-down"

blind pew

29th Nov 2010, 10:10

The film was ALL IN A DAYS FLYING - 1965 director Richard Dimbleby and narrated Johnny Morris who did Animal magic.
It showed a VC10 trip with captain Bill Williams and his son who was at Hamble at the time as well as a Trident one with a GVA and Nice turnaround with shopping excursions. ( Nice was rather impoverished at the time)
The Trident 1 carried out a typical controlled crash - no real attempt to kick off the drift or flare.
We all winced when we were shown it during current affairs at Hamble - thought that the landing should have been left on the cutting room floor!
It was shown as a B movie and for recruiting for the corporations.
Still available for around a tenner from Phil Nelson - link via the Hamble website.
A very good example of the privileged life of a pilot in both of the corporations at the time.
I was one of a handful of guys who experienced both the gripper and the Iron duck.

forget

30th Nov 2010, 11:56

Speaking of the Trident wing versus the 727 -take a look at this cracking shot. The way that wing 'came apart' always impressed me.

http://www.pprune.org/spectators-balcony-spotters-corner/415919-m-fahd-b727.html

Wookey

2nd Dec 2010, 09:48

Have enjoyed reading this thread. Flew a lot on Tridents (as SLF) from the mid 70's and loved the aircraft from a pax point of view although some interesting moments.

Any support for a Trident thread on AH & N for some more of those stories?

blind pew

2nd Dec 2010, 12:09

Prober - was it Capt. Ormonroyd who was the intrepid aviator that removed the Comets fin in a low go-around at Bedford?

ASN Aircraft accident de Havilland DH-106 Comet 3B XP915 Bedford-Thurleigh Airport (http://aviation-safety.net/database/record.php?id=19710119-1)

It was in the days of training accidents seemed to be part of normal life in the BEA group (several tridents, the odd Vanguard and Airtours 707).

Cremeegg

2nd Dec 2010, 13:00

Thanks for that Pew - hadn't heard of that one although my father told many tales of many others. He'd spend weeks on T1's and T2's at Shannon and Prestwick doing base training at a time when fuel was cheap and I presume simulators poor. He certainly got rather tired of being required to use autoland as often as possible to build up the reference database. He claimed that the passengers didn't like it as it was prone to give a rather more agricultural arrival than the manual version. I presume today it'd all be done on the simulator.

slast

2nd Dec 2010, 14:48

errrr.... what's AH &N?
(And while I'm displaying my ignorance, where on PPrune does it tell you how to insert quotes in messages?)
Steve

Escape Path

2nd Dec 2010, 14:57

Aviation Hobby & Nostalgia :cool:

Wookey

2nd Dec 2010, 15:18

Try this?

http://www.pprune.org/aviation-history-nostalgia-86/

slast

2nd Dec 2010, 15:39

The 1st Trident sims were very sophisticated - by the standards of the day!!

I was on one of the first Hamster courses so if cremeegg's dad was a trainer he may have done me.... be interesting to know but would kind of bust your anonymity. Anyway at that time (winter 65-66? again I'll have to find the logbook) the sim. was not approved for stall training, so we did full aerodynamic stalls in the aircraft at Shannon. Must have been exciting for those skippers, with a kid with all of 250 hours in each of the other 2 operating seats, and a T-tail aircraft with a known deep stall potential! The supervisory F/Os assigned to "mentor" us had their work cut out and were outstanding guys as well.

One story about the Shannon Base Training.

We were on day 1, Geoff Fowkes (lovely gent) was the boss. We must have spent 45 mins doing the preflight setup (remember we had no "part function simulators" or "procedures mockups"), while the Shannon ground mech is hanging around underneath on the headset in the winter breeze. Eventually Geoff says "Hello Ground, we're ready to start".
"Sorry skipper, it'll be just a moment now, we've got a shift change". Click of intercom, we watch him walk off to the hut. We twiddle our thumbs for 10 minutes and there's another click on the intercom. "OK skipper you're clear to start now".

Geoff: "are you the gentleman who was here before?"
Ground "that's roight"
Geoff "I thought you were having a shift change?"
Ground "That's roight, oi'm on a double shift today! Do you want to start up?"

So we start, taxy off and fly circuits for several hours before returning to the pleasures of the Limerick Intercontinental Hotel, our first experience of the lavish lifestyle we were to become accustomed to as "BEA pilots on the fastest jet airliner in the world" (well it was at the time !!)......

Wookey

2nd Dec 2010, 16:10

As not much response to my suggestion that a new thread on AH&N might elicit more fascinating insight into this aircraft maybe a new technical question - Mods feel free to move/delete or suggest a completely new thread if you feel too much thread creep here!!

From my few visits to the 'Best Seats In The House' end of the Trident I recall that it apparently had a moving map display which seemed to consist of a paper (?) scroll and a moving pen? I cant imagine how this worked let alone how you guys used it on longer sectors.

ChristiaanJ

2nd Dec 2010, 16:38

Wookey,
It seems most of the Trident crowd has congregated here, so why not stay here?

"....a moving map display which seemed to consist of a paper (?) scroll and a moving pen?"
Ah, you're opening a new can of worms as well!
No, the scroll was some type of Mylar, and the moving pen was a moving marker.
But I'm as curious as you to hear a bit more about its workings!

By the time Concorde came around, they'd progressed to a projected moving map display, using projected maps stored on film.
And in the case of Concorde it was thrown out almost as soon as it arrived... a bit useless over water, and replaced by the INS.
Only the prototypes had it, and even then only in the earlier days.

CJ

petermcleland

2nd Dec 2010, 18:33

The moving map was worked by "Doppler" and that also showed on the Doppler Ground Speed and drift instrument above it. The First Officer put the Doppler map position right occasionally when passing a fix. Then it did its own thing by applying its own calculated speed and drift. It did not, in my experience, do this very well and I always said that Doppler was only right when the First Officer had put it right!

dixi188

2nd Dec 2010, 19:39

slast

2nd Dec 2010, 20:04

The Doppler navigation used a x-shaped antenna in the belly - it rotated so that when each side was reading an equal groundspeed the angle relative to centreline = drift.

There’s more info on a couple of other pprune pages and a good photo at Photos: Hawker Siddeley HS-121 Trident 3B Aircraft Pictures | Airliners.net (http://www.airliners.net/photo/BEA---British/Hawker-Siddeley-HS-121/0643499/L/&sid=fae9c37304bf4661a5439f2e489d3b00)

The Special Reactive Instant Navigation Geographic Current Location Indicator Pointer” (SPRINGCLIP) fixed just above the map in the pictures is holding a bare metal rod I think, initially there was a pen with a little ink reservoir on it. The idea was to have a permanent “flight recorder readout” of actual track flown for record purposes e.g. to improve airspace usage etc., most F/Os were glad that got dropped pretty early as there was often more ink on fingers than map! Also the maps had to be route specific so started to be significant cost as single use items.

Drift could be fed to the autoflight system, in fact IIRC the steering was actually looking to keep commanded track not heading per se. Just below the compass you can see a horizontal rectangle with 4 white marks on it (can’t remember what they are). This covered a drift selector, with it open you set drift yourself (e.g. to fly radar heading set it to zero) and with it closed as in the picture drift was auto. (I think!!)

The current “actual drift and G/S” are just above the map in the picture. As PeteMcleland has just pointed out this could be adjusted because Doppler wasn’t always reliable especially above e.g. smooth water or snow. The adjustment was by an X shaped switch at the rear of the centre pedestal. Move the switch > change the drift and groundspeed readouts. As Peter says the actual display motors could also be adjusted to drive the pointer around the map.

Voice activated autopilot. This was a very advanced feature only occasionally demonstrated to a certain category of SLF. It was only available after the introduction of the Cockpit Voice Recorder and required good outside visibility. The mike for the CVR was located in the overhead towards the back of the centre panel. Remember the Gripper had 3 pilots. Remember F/Os flew alternate legs as RHS pilot and “Flight Engineer” (all qualified in both seats). Also we operated with noise muffler headsets and used intercom as standard.
Suitable SLF asks usual questions – gosh isn’t it small in here, do you understand all those knobs and dials, what do you do all the time ‘cos it’s all automatic now isn’t it?” 2 front pilots deal with SLF questions, P3(F/E) apparently oblivious of visitor.
Response to question 3 “yes it’s so automatic we don’t even have to turn any knobs any more, it’s voice activated”
“NO!?!”
“want a demo? OK lean forward a bit and speak into that mike.” (You see where the SLF needed appropriate qualifications now) “ Say clearly “TURN LEFT”.
SLF: “TURN LEFT!”
P3's left hand resting nonchalantly on rear of centre console increases right drift ……. Autopilot senses drift error, banks aircraft left …………
You get the drift I’m sure….
Steve

ChristiaanJ

2nd Dec 2010, 20:50

slast,
Steve... ROFLMAO re the VOAP....

Thanks for the other info too.... so I was wrong, and it was indeed paper at the time. (Love the perforations...)

dixi188,
The Doppler of course was "dead-reckoning" and "self-contained" if indeed less accurate than INS or nowadays GPS.

Decca would provide a "true position", but IIRC, by that time Decca coverage (being ground-based) was totally inadequate for the typical BEA route structure.

Looking forward to more info.

CJ

Hobo

2nd Dec 2010, 21:29

Steve,

where on PPRuNe does it tell you how to insert quotes in messages?)
Steve

Above the box where you type your words into your post there is a small yellow cartoon quote. Highlight any of you own text or any you have copied and pasted, and click on this.

Flew all the Tridents for 14 years (once or twice with you)....happy days.

Prober

2nd Dec 2010, 22:04

No, I know who I think it was. All I can say is that Capt O was NOT cocky, but apart from that I had better go no further.
Prober

petermcleland

2nd Dec 2010, 22:17

I thought the Trident had Decca Harco navigation with moving map display.
I seem to recall that it was fitted to the BAC 1-11s of BEA also.
I saw a few of these at Hurn in the early '70s.
I also worked on a Jetstream and a Hughes 500 with Decca Danac which was similar to the Harco.

The Super 1-11 had Harco and I loved it...I only flew it as a First Officer and I remember that some Captains were not to happy with it. I remember you had to remember a particular circuit breaker to punch in and out a few times on the first trip of the day if it was reluctant to wake up...After that it was good as gold!

I never flew the Trident as a First Officer but I flew the Trident 3 as Captain from 1975 till it retired in 1985...36794 in your logbook if you flew with me :)

Trident Sim

2nd Dec 2010, 23:41

Peter

36794 in your logbook if you flew with me

My logbook has your signature and that very number by some sectors on 05 Oct 83 and also 10 Feb 84.

And a similar signature on my membership card for a club in North London!

Good to hear from you, and I trust all is well with you Peter!

Best Regards

Trident Sim

blind pew

3rd Dec 2010, 07:24

Trident simulator visual.

The Trident sim was fitted with a visual display - it was a rubber conveyor belt around 6 ft wide and 20 ft long and mounted vertically.

The black and white TV camera was mounted above it and positioned by two threaded rods to give vertical and horizontal displacement from the belt centre line.

The cloud base was controlled by a sheet of frosted glass positioned in front of the camera.

The airport buildings and runway were made of paper and card with trees and grass made form those bits of kit used by model railway enthusiasts.

On one of the last exercises taken by a non flying simulator instructor I was given a main gear collapse after landing, the belt flexed and the camera lens touched the paper runway.
Unfortunately for the crews for the next few days the lens tore the paper which proceeded to peal away in an ever increasing roll.
I shouted to my fellow trainee to duck as we were going to hit a road roller and we careered across the tarmac and destroyed the hangar.

We P****d ourselves and were taken down into the guts of the machinery to see the results of our incident - looked like the bark on a silver birch.
The instructor had humour failure and talked about the consequences for us but after I reminded him that he had initiated the gear failure he calmed down but still didn't see the funny side of it!

Fortunately never did the Trident high fly but was told of a stick push exercise which nearly went wrong - the nose just remained pointing skywards after the push fired - it took several seconds before it slowly descended!!!!
Believe it was stopped soon afterwards.

Did a High fly on the Duck though - scared me s******s.
We didn't do the full Trident stall rubbish but dutch roll recovery. I still believe that dutch roll was a necessary exercise whereas the stall exercise was stupidity personified.
The Duck had a periscope to observe the huge T tail. The exercise was limited to 30 degrees of bank after a trainee had put in the wrong correction with 60 degrees of bank and got the wings through the vertical.
I am still amazed how much the T tail flexed without breaking off - the tips must have moved at least five feet.

My only real emergency was a dutch roll type of incident on the Duck when we thought it was going to break up - after declaring a mayday, reversing course and initiating the descent I decided to try and hand fly it - contrary to my trident teachings - the movement had got so bad that ceiling panels were falling down.
Punched out the A/P and the dutch roll type of movement stopped - runaway roll or yaw damper which apparently had never happened before.
Got plastered in Hong Kong.

Wookey

3rd Dec 2010, 08:45

Moving Map Display

Thanks for the explanations so far. This is probably a stupid question but looking at the picture link from slast's post it seems that the map movement was up and down ( north/south) while the pointer/marker could track sideways (W/E). What happened if you were flying a sector with a significant W-E component? Was the map scale adjusted to allow for the travel limitattions of the marker. If this was the case how positionally accurate would some of the longer W-E sectors be, say London - Moscow (if the Trident operated this route).

THICKO

3rd Dec 2010, 09:25

I seem to remember that the map roll was oriented with the E-W bit to N-S if you see what I mean! :)

Wookey

3rd Dec 2010, 09:43

Wow bet that was interesting. Cant imagine trying to read my sat nav rotated through 90 degrees !

DozyWannabe

3rd Dec 2010, 11:02

It's what you're used to, isn't it? Modern civilian satnav wouldn't hit the market until nearly 40 years after the Trident first flew!

The technology might have been a bit steampunk by comparison (with attendant reliability issues), but some of the innovations in the Trident's avionics were truly special.

I don't think she'd have had the range for London to Moscow though... ;)

petermcleland

3rd Dec 2010, 11:07

Peter

My logbook has your signature and that very number by some sectors on 05 Oct 83 and also 10 Feb 84.

And a similar signature on my membership card for a club in North London!

Good to hear from you, and I trust all is well with you Peter!

OK, I know who you are then...How nice to hear from you again. Yes, all is well with me I took early retirement when the Tridents went and I came to the Southwest with my boat and married again. Are you retired now?

Wookey

3rd Dec 2010, 11:10

Longest sector I travelled on a Trident was Tel Aviv - LHR (needed a tech stop in geneva as I remember) which has a significant W-E and N-S component. Again can I ask if the map scale is adjusted to allow for this and if so how accurately were you guys at the front able to establish your position?

DozyWannabe

3rd Dec 2010, 11:22

I have no personal experience, but there's a good thread on it here...

http://www.pprune.org/tech-log/384288-moving-maps-displays-ancient-mechanical.html

ChristiaanJ

3rd Dec 2010, 11:28

Wookey,
London-Rome would also be SE-NW.
I hope somebody will confirm this, but I would expect they would be route maps, oriented along the track from A to B, rather than oriented N-S or E-W, and that when operating a given route you would have loaded the relevant map.
Not sure how you coped with a significant diversionn though.

This was long before you could put the entire map of Europe and the display electronics into a little box the size of a cigarette package .....

CJ

petermcleland

3rd Dec 2010, 11:56

No, no, each sector had its own roll and it was track orientated...Same as Harco. You picked up the map roll with all the other clutter for the nav bag at briefing. Navigation on the Trident was certainly NOT done with the moving map...It was done with VORs and NDBs as indicated on an RMI. You could lock the autopilot to a VOR radial and uncage the drift shutter if you wished but mostly the autopilot would be locked to Heading and the handling pilot would steer with the heading pointer knob on the compass, changing heading as the RMI needle swung round to indicate the passage of a fix and make a small allowance for drift as appropriate.

We didn't have glass cockpits in Tridents you know!

Here an old picture in the cruise...Note the MachNo:-
http://www.petermcleland.com/trident/Trident010.jpg

WHBM

3rd Dec 2010, 12:10

Seeing as all you great Trident guys are here, can I please ask a few questions.

How much was the extra "half engine" actually used on the Trident 3B, was it only if the boost was really needed ? Was it eventually given up and removed ?

Why was the nosewheel offset when virtually every other manufacturer managed to design it in the centre. Did it make any difference when taxiing ?

As the Trident was used on many of the sectors to socialist eastern Europe at the time (1960s-80s), what were the loads like ? Is it true that these trips were often operated virtually empty ?

Wookey

3rd Dec 2010, 12:28

Great picture Peter and thanks for the explanation. I think I now understand the process much better!!
Mach no. noted as well. I seem to recall from a friend who used to fly Tridents that he called the T2 the GT version as it had better performance than the other variants.

petermcleland

3rd Dec 2010, 12:54

Yes the T2 was the sports car varient and it climbed higher up to about 42,000 feet...The T3 was limited to 35,000 feet and had no "Drop Down" passenger oxygen system. The plastic Boost Engine had 5500 lbs of thrust and you used it for take-off if the runway length or air temperature were limiting. You could also light it in the air if extra thrust was required if you had lost a main engine.

I did lots of Warsaws on the T3 and it was always very full...Often with no seats left at all.

The sideways retracting nosewheel saved an enormous amount of space to put the electronics bay in.

Cremeegg

3rd Dec 2010, 12:56

Moscow was certainly a regular non-stopper with, I believe, only T2's. My father had an unscheduled week there trying to fix a couple of errant starter motors. Remember him talking about some "interesting" readings on the radiation meter as they flew over certain parts of eastern Europe.

Tel Aviv also a regular non-stopper - out and back. Again I think only with the T2. Used to have huge bags of citrus fruit brought back from those trips that the family much enjoyed.

bizdev

3rd Dec 2010, 16:15

I was told that because the Cat3 autoland was so accurate the nose gear had to be offset to prevent discomfort to the pax as the nose wheels would be bumping along the runway lights!!!!!! :E (I was an apprentice engineer at the time and believed everything the old salts told me)

WHBM

3rd Dec 2010, 16:54

...The T3 was limited to 35,000 feet and had no "Drop Down" passenger oxygen system.
All those years of pax briefings on the Shuttle T3s (and also the T1s they used at first) and I never noticed this. The Caravelle was the same but when these were sold to United Airlines in the US the FAA would not allow this and they had to be re-engineered with an overhead oxy system. The Trident of course was never certified in the US - or was it ?

petermcleland

3rd Dec 2010, 17:33

All those years of pax briefings on the Shuttle T3s (and also the T1s they used at first) and I never noticed this. The Caravelle was the same but when these were sold to United Airlines in the US the FAA would not allow this and they had to be re-engineered with an overhead oxy system. The Trident of course was never certified in the US - or was it ?

That was the reason for the 35000 feet altitude limit...No drop down Oxy. No, I don't think it was ever certified in the US.

blind pew

3rd Dec 2010, 18:39

Cremeegge
I was the stooge who worked outside with our traveling engineer while your dad drunk coffee in the warm! :):)
It was around zero and slush everywhere.
The procedure was to start engine 2, remove the starter motor, fit a blanking plate which was carried in the engineers kit and then mount the starter on engine three.
After we started two we refitted the starter to engine three but it wouldn't start - I thought we had got the starters mixed up and we swopped them around - no joy.
We had already re-fueled after the first starter had broken - it took nearly an hour to carry out the procedure in the dark but with another good hour and a third re fueling in Moscow your dad decided we would run out of hours and we night-stopped. Fantastic decision!!!!!
The starter motors were flown in the next day on the subsequent service and we flew back with a couple of pax only.
I always suspected that the starter motor had gone bang ex LHR after some engineering bodge - it was the only time I ever had a starter motor failure in my career- let alone two!
In those days we often had a lot of carry forward defects as well as prodigious tech log entries "ground tested and found satisfactory".
The night stop was a hoot - although we didn't have a room party as Male and females were on separate floors with a granny sitting at the end of the corridor.
Station gave us a briefing about the KGB and BOAC who had unscrewed a chandelier floor mounting plate believing it was a secret microphone causing the chandelier to crash to the floor below.
The hotel room was similar to a french one - cold with a trickle of brown water running out of the tap - brushed our teeth with champagne.
The next day we paraded around Red Square in our uniforms jumping all of the queues into the churches. We got as far as jumping a 1/2 kilometer queue into Lenin's tomb but couldn't be a*****d just to see the coffin.

Moving Map

Played a prank once with a new skipper who decided to have a kip on a night med flight - probably Malta.
When he went to sleep I unplugged his head set jack plug.
We got descent with London ATC and took out all of the manometric locks, slightly throttled back and started the descent on pitch wheel.
It meant that the autopilot annunciator panel was blank - We always included it in our scan to understand what the autopilot was trying to do.
This was followed by winding the doppler map to it's very end - think it had the sector details on it.
All of our radio aids were detuned and P1s jack plug was replaced.
Waking up he would have immediately assumed that we had overflown Heathrow and that the aircraft was descending out of control.
As he stirred we assumed sleeping positions but out of the corner of our eyes we watched the panic dawn over his less than angelic face.
Dare not write the expletives down.
Bet he didn't let his FOs do all of the work on a night flight again!

Trident Sim

3rd Dec 2010, 23:19

Peter

Private message sent.

Best Regards

Trident Sim

Hobo

4th Dec 2010, 05:18

Jo90

4th Dec 2010, 09:53

I've been trying to remember the type number of the boost engine but no joy.

I believe it was originally designed to provide vertical lift for some proposed vtol fighter that never got built. Consequently it had a very high thrust to weight ratio largely because it had no starter motor, no generator or hydraulic pump to drive, only minimal anti-icing and not even an oil pump. Probably the only commercial jet engine to run with zero oil pressure!

forget

4th Dec 2010, 10:01

Trident fourth engine.

Rolls-Royce RB162 - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Rolls-Royce_RB162)

Rolls Royce RB162 Cutaway - Pictures & Photos on FlightGlobal Airspace (http://www.flightglobal.com/airspace/media/aeroenginesjetcutaways/rolls-royce-rb162-cutaway-5643.aspx)

petermcleland

4th Dec 2010, 10:45

I was P3 on a LHR-GLA trip, when climbing through about FL150, I noticed a slight whistling coming from the back of the flight deck. This gradually got louder, and I drew it to the attention of P1/P2. They thought they could both hear it and P1 scanned the pressn panel and said 'probably a loose door seal - put it in the book for GLA to look at'.

It gradually got louder. Passing about FL230, I noticed that I had left the manually operated dump valve fully open - left open for T/O and closed shortly therefafter. Very slowly, to prevent any surging, I wound it closed with my right foot. Sure enough the noise stopped. Passing about FL280 I asked P1 & P2 if they could still hear the noise, as I couldn't detect it any more.

They couldn't and commented that 'these door seals often sort themselves out'.

I then owned up, when P1 said he had done exactly the same as P3 on a Comet - but on that occasion, he hadn't noticed until the 'rubber jungle' appeared.

PMc, do you remember doing a block of work 28-31/1/80 including 5 CATIII approaches (@ LHR BFS & GLA), including, on one of the GLA's ex LHR 28R, #1 blowing up on rotation, with an incredibly long and loud graunching sound - we all thought the U/C had collapsed as I rotated - closing the R/W for an hour while it was swept of fan blades, with a subsequent 2 eng landing on 27L in about 800m? As if that wasn't enough, we ended the block with a night Malta! Apart from Malta, we reckoned we did't see the ground above 200' all week.

Yes indeed "A"...I remember that number 1 engine blowing up as you rotated, very well. I remember that the bang was so loud that I thought we had hit a vehicle. I also remember, after sorting out the close down drill and keeping an eye on your flying, that my ASI needle sat very nicely on the yellow bug...Not just nicely but EXACTLY in the centre of the yellow bug. I also remember that I was so impressed that I left the controls with you for the assymetric landing back at Heathrow and a very nice job you made of it. I still have a mangled turbine blade from the runway sweep up. The engineer gave it to me as we were doing all the paperwork, prior to moving over to the replacement aeroplane now full of our waiting passengers...Oh yes! I remember it well :)

WHBM

4th Dec 2010, 11:15

PMc, do you remember doing a block of work 28-31/1/80 including 5 CATIII approaches (@ LHR BFS & GLA),
I am wondering if this is the same winter's time (because it was around then) when I was paxing extensively up to Edinburgh and back, it had been dreary grey on the ground for many days. Departed Heathrow at 0800, straight up into the stuff for several minutes, and with a good rate of climb the Trident burst out of the top into bright sunshine. The whole cabinful of suits (as we all were on the Shuttle at such a departure time) all went "aaaah" as it did so !

slast

4th Dec 2010, 16:48

The Trident sim was fitted with a visual display - it was a rubber conveyor belt around 6 ft wide and 20 ft long and mounted vertically. The black and white TV camera was mounted above it and positioned by two threaded rods to give vertical and horizontal displacement from the belt centre line.

Ah, the canvas countryside conveyor!! I thought my career was over with that thing. Not the Trident one actually but a similar thing on the Vanguard /Merchantman. It worked by projecting the TV picture onto a set of mirrors in front of you.
After 9 years almost to the day as a Trident man (boy really!) and still with only 2 stripes I got a Merchantman command. Did the 1st days sim with my “buddy” then had 2 days sick and had to catch up.
So it a dark and stormy night, and it was me and a ground instructor who I think was probably a retired Base Training Captain and not too pleased to be spending Christmas Eve in an otherwise almost totally deserted Heston Training Centre doing exercise 2, engine failure RTOs. Careful explanation of what to look for – stop the nose swing, instruments move, etc. The emphasis was on watching for a heading change on the compass I think. The Trident had pretty good clear Smiths SEP5 instrumentation and of course virtually no swing on losing an engine. The Merchantman had the Smiths Flight System (in my opinion the worst instruments ever designed) and of course big asymmetry! So this was a big deal for a Gripper boy.

Anyway line up on that cardboard runway with the grey flickery TV visual, instructor in RHS opens up, we accelerate, he pulls an engine, I think I am correcting the right way but can see the runway swing, frantically try again and the world goes mad as we ground loop off the runway.
Instructor says patiently “you corrected the wrong way didn’t you” and goes through it again. Repeat exercise with same result. And again. And again. My heart rate is rising exponentially. His patience is getting sorely tested! I am sure I am doing what he is telling me to and the damn thing is not responding correctly - poorest excuse ever but I can see my career vanishing down this black hole! Eventually he says “look I’ll show you”.

Instructor in RHS opens up, accelerate, he pulls an engine. We see the nose swing, and the world goes mad as we ground loop off the runway.

Long silence then instructor says “There IS something wrong here!” and swiftly departs the sim to get the engineers. Leaving me to deep contemplation of bad news for Christmas. When he returns I timidly point out my recollection that when I saw this on day one, the “airport buildings” were on the left – now they are on the right. Lo and behold the engineers had been working on the visual, and had somehow reassembled it so the runway image was for the reverse of the simulator direction, e.g. the sim thought it was on r/w27 while the image was for r/w 09. Or something. Don’t ask me to explain how you would do that. Anyway if you tried to correct a swing on the visual, you actually went in the wrong direction. In retrospect I can’t understand why we didn’t detect it even before the failure, I suspect that I was keeping straight by a combination of being frozen with fear, focus on that damned compass, and a combination of errors which totalled out to zero!
Anyway they fixed it an I eventually got one nailed for Christmas. And was very glad to get back to the Trident about 2 years later!

slast

4th Dec 2010, 16:55

does anyone remember Capt Jimmy Green c 1967 (ish) a BEA Captain?
My earliest record of flying with a Captain Green is LHR/FRA/LHR 4 May 1966, and apparently we did the famous runway 25 high level penetration, but I am not sure if it was Jimmy Green, there was at least one other, Neil I think.
Steve

arearadar

4th Dec 2010, 18:22

What DO you know?

The `gripper` or `ground hugger` as the Trident 1C was affectionately known to us in ATC, was due to the fact that it only ever got airborne due to the curvature of the earth.

A friend of mine, a British Eagle BAC-11 skipper said that aslong as he was stabalised he would select reverse idle over Heston, landing on 28R (27R to the youngsters).

I understand that DC-8 were certified to select reverse at altitude to inccrease descent rates. (all models ?)

Dave:)

STBYRUD

4th Dec 2010, 18:42

So was the Concorde ;)

Crosswind Limits

5th Dec 2010, 13:56

to arearadar

I know absolutely nothing or very little, hence my question! ;)

Glad to see the thread develop so well. All interesting stuff - keep it up!:ok:

slast

5th Dec 2010, 15:01

If you look at http://upload.wikimedia.org/wikipedia/commons/5/51/TridentFlightDeck.JPG
and zoom in on the rear of the centre console you will see the map display control panel immediately in front of the Nav 3 display and APU temp gauge. IIRC the system was told the general orientation of the map centreline (in this case "C" "1" and the pen could be driven about the map with the 4 pushbuttons - left/right moved the pen horizontally and up/down moved the map roll. The Doppler controller is to the right of the APU Temp.

forget

5th Dec 2010, 15:12

Ref the above photograph. ....... I may well regret this - but I have to ask. Why are the Intercomm and Press to Talk switches on the inboard side of the yokes. :confused:

ChristiaanJ

5th Dec 2010, 15:24

slast,
Thanks for that link!
It's rare to find a photo that's so hi-res that you can read practically all the legends.

forget,
I suspect you'll get the answer in the form of another question...
"Where are your thumbs?"

CJ

slast

5th Dec 2010, 15:34

Christiaan J has it I think!!
unless you mean why are the yokes symmetrical as opposed to identical, in which case I don't know - clearly the A/P disconnect button and radio switches work on either side of a yoke!

forget

5th Dec 2010, 15:45

Well every aircraft I've ever known has those switches outboard so you can switch and use your inboard hand for whatever, things like knobs and levers and throttles. From what I can see the Trident is unique so the question stands - why?

And while I'm here - did the Chinese Tridents have a conventional yoke? According to one web picture they did. :bored:

ChristiaanJ

5th Dec 2010, 16:20

forget,
Apologies for having misinterpreted your question.
And I'd even add another question... if the outboard button is indeed the A/P disconnect, why is it so big?
It almost looks like a precursor of the 'coolie hat' four-way trim button, but I doubt it is that.

CJ

slast

5th Dec 2010, 16:26

Don't know the answers to those questions I'm afraid. I did over 7500 hrs and probably over 5000 sectors on it in both seats, and it never crossed my mind that either set of buttons wasn't well placed!

ChristiaanJ

5th Dec 2010, 17:05

slast,
Since you flew the beast... for this (avionics and AFCS) ancient, could you just confirm that big 'outboard' button is indeed the "instinctive A/P disconnect"?

CJ

forget

5th Dec 2010, 17:15

Thanks slast. This is intriguing. Why did the 'where to put what committee' decide that the A/P cut-out was best placed on the outboard yoke? Or is there another reason? :confused:

I can see this as being a minor pain to convert to/from Tridents.

DozyWannabe

5th Dec 2010, 17:32

Interestingly on this thread, our own Bellerophon considered the Trident yoke to be better designed than that of Concorde:

Concorde Style Yoke — Tech Ops Forum | Airliners.net (http://www.airliners.net/aviation-forums/tech_ops/read.main/267786/)

I can't see any "press to talk switch" inboard though. It would make a lot of sense if the outboard button was indeed the "press to talk", because if one were using the yoke one-handed while operating the panel with the inboard hand, there'd be less chance of inadvertently knocking the inboard selector switch.

Regarding conversion, remember the Trident was designed in the late '50s. Ergonomics was in its infancy and commonality across types was practically unheard of!

slast

5th Dec 2010, 17:56

Christiaan,
yes.

petermcleland

5th Dec 2010, 18:00

slast,
Since you flew the beast... for this (avionics and AFCS) ancient, could you just confirm that big 'outboard' button is indeed the "instinctive A/P disconnect"?

Well I'm not Slast but I can confirm that big button is the Autopilot Disconnect and if you have your left hand on the left grip then your left thumb naturally rests on that button. That is handy on an Autoland as the your first action as the wheels touch the ground is to press that button.

Edit...sorry Slast...Crossed!

forget

5th Dec 2010, 18:05

Dozy, this is the FO's yoke. You can see the switch is marked OFF - I/C - OR(?).

OFF is Intercom OFF. I/C is Intercomm ON. OR(?) is Radio Transmit and is spring loaded to I/C. I've checked other pics of other aircraft, lots of 'em. They all make sense - apart from the Trident.

http://i21.photobucket.com/albums/b270/cumpas/trident-3.jpg

JW411

5th Dec 2010, 18:12

I have only just found this thread. Some of you might not realise that the Belfast had the same auto land system as the Trident and in fact did a lot of the system proving trials.

Now the Belfast also had a "rams horn" type of control column which I found to be very comfortable.

I have just looked at my old Pilots Notes and I can confirm that on the cockpit photographs the disconnect button for the automatics were on the left side for the captain and the right hand for the F/O. The PTT/intercom buttons were inboard.

This seems very logical to me. We had a set of throttles each so it seemed right to have your outside hand on the control column and your inside hand on your own set of throttles with your thumbs close to the disconnest buttons for the automatics and the auto throttles.

Hobo

5th Dec 2010, 18:17

1063? Fairly high pressure day then!

....PM - I've still got a couple of those melted blades myself! It was my 2nd engine failure - I seem to recall it was your first - do I remember P3 telling us it was his 8th?!! 30 years ago and it almost seems like yesterday. Great days eh?

forget

5th Dec 2010, 18:33

... so it seemed right to have your outside hand on the control column and your inside hand on ... throttles with your thumbs close to the disconnect button for the automatics and the auto throttles.

Can't disagree with that - as I said. Just include the 'radio switches' on the outboard and everyone's happy. :) I knew about the Belfast Autopilot but I couldn't find a decent cockpit photograph. The only one I've seen doesn't (seem to) show a huge A/P cut-out, a la Trident.

PS. Interesting - from Wiki.

The Trident’s autopilot had separate engagement switches for the pitch and roll components, and although the normal autopilot disengagement was by means of a conventional control yoke thumb-button, it was also possible to disengage the roll channel while leaving the pitch channel engaged. In these operations the pilot had acquired full visual reference, normally well above decision height, but instead of fully disengaging the autopilot with the thumb-button, called for the second officer to latch off the roll channel only. He then controlled the lateral flight path manually while monitoring the autopilot’s continued control of the vertical flight path – ready to completely disengage it at the first sign of any deviation. While this sounds as if it may add a risk element in practice it is of course no different in principle to a training pilot monitoring a trainee’s handling during on-line training or qualification.

slast

5th Dec 2010, 19:59

I think in fact the switching was push forward to transmit, centre position was off, down was intercom and the O/R position was" over-ride".

forget

5th Dec 2010, 20:39

In fact I think you're right. Is the Txmt bit over the top and unseen in the pic above? What was O/R for? (Hard to believe I worked avionics in BEA hangars very early 70s; 1-11s, Merchantmen conversions, and Tridents. :hmm:)

Hobo

6th Dec 2010, 04:31

slast is right, forward to transmit - you can't see the decal in this pic.

Having flown a 'conventional' Seattle made yoke before the Trident (and afterwards) the rams horns with its switches was no problem and was completely intuitive - I never gave it a thought until now.

In fact, I think the rams horns made very accurate manual flying easier.

petermcleland

6th Dec 2010, 11:37

....PM - I've still got a couple of those melted blades myself! It was my 2nd engine failure - I seem to recall it was your first - do I remember P3 telling us it was his 8th?!! 30 years ago and it almost seems like yesterday. Great days eh?

I'm pretty sure that it was my only engine failure in BA...Although I did do a three engine ferry on the Vanguard. I had a few engine failures on fighters in the RAF and one of those involved a dead stick wheels up landing...The others I managed to relight.

I expect you are finding like me, that time flashes by at an incredible rate when you are retired...Every time I reach an age, devisable by 10, when I thought I would be old, I find myself saying "No I won't be properly old till (age+10)". I'm approaching another one of those points and wondering if I will say it again. :)

Yes they were all great days and I find myself thinking about them a lot. Here is a PowerPoint presentation that I made this year about events in my life Fifty years ago:-

http://www.petermcleland.com/powerpoint/208_Squadron_in_Kenya.pps

The download will take at least 5 minutes and you must have Microsoft's Powerpoint to view it...A free download of Powerpoint Viewer can be obtained here:-

Download details: PowerPoint Viewer 2007 (http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=048dc840-14e1-467d-8dca-19d2a8fd7485)

Nice to speak to you again "A"...Surprised to find this much interest in the old Trident.

blind pew

6th Dec 2010, 14:52

P3's responsibility on every autoland was to monitor the autopilot's performance and latch off the autopilot in the event of a failure.
(he was bent forward and had his fingers stretched across the pedestal and resting on the AP engage levers from around 1000ft).

Can't remember all of the functions but one was possibly the kick off drift and It's associated green light??????
Think there was a latching indication for either roll or yaw damper and also a dolls eye for when the ILS (loc and/or GS?) had been captured.

INTERCOM.

Think the O/R position would block out all other inputs to the headsets and override the Off position.

It was the only aircraft I flew and only used I/C to communicate between FD members- I was told it was a legal requirement!

Witnessed a captain insert two butter pats under the headset speaker cotton covers of a colleague who had a reputation for verbal diarrhea when the victim went into the cabin - It took about 15 mins before we noticed the butter dribbling down his cheeks and an another 5 before the guy saw the mess on his trousers. - Kept him quiet for about 10 mins.
Still brings tears to my eyes..............

blind pew

6th Dec 2010, 15:03

For all you Trident aficionados passing near to heathrow - BA has an excellent museum 2 mins walk from hatton cross tube station.
It is staffed by volunteers and you need to make an appointment but it is well worth the visit. Allow yourself a couple of hours and take a packet of biscuits along to complement the free mugs of tea (the staff really appreciate good ones).
There are all of the aircraft manuals, some of the old uniforms which bring back far too distant memories - the B-Cal kilts, the BOAC pinafore dresses of the early 70s and not forgetting the last BEA one with a wrap around skirt!!!!!

And for the gruesome lots of the old flight safety reports and I mean lots!!!!!

Spent 3 days researching their archives.

WHBM

6th Dec 2010, 15:41

Here is a PowerPoint presentation that I made this year about events in my life Fifty years ago:- ....... The download will take at least 5 minutes and you must have Microsoft's Powerpoint to view it.
67 mb for those who have bandwidth limitations. Interesting photos of East Africa. Half those cars look pre-war.

petermcleland

6th Dec 2010, 16:18

Well it should be a little over 100MBs so you may have been limited yourself...It may be better to choose "Open" rather than "Download" and then select "Open with Microsoft Powerpoint"...I think that makes the file just Temporary rather than permanently cluttering up your disc space :)

Oh yes, it has music so you might want to turn the volume off or up according to taste!

slast

6th Dec 2010, 16:46

Forget, Dozy…..

Interesting you refer to the 'where to put what committee' and to “remember the Trident was designed in the late '50s. Ergonomics was in its infancy and commonality across types was practically unheard of!” While I’m pretty sure the decisions in this case were taken in-house, I don’t know how much awareness there is of the airline industry's actual cockpit “where to put what" committee. It dates from the late 1940s when the US airline industry started acquiring lots of ex-military transport aircraft, which came with a variety of instruments scattered in all sorts of places and ended up in accidents because the pilots became confused about what was where on different aircraft of allegedly the same type.

I believe it was Scott Flower who was chief (test) pilot for Pan Am who got some of the other chief pilots together to try and get some standardisation into civil cockpits, and started with really enforcing the implementation of the “Basic T” that we see today. That kind of work became formalised under the banner of the Society of Automotive Engineers as “SAE Technical Committee S-7, Flight Deck & Handling Qualities Standards for Transport Aircraft”.

I had the privilege of being a member of it for quite a few years and chaired it for a while before I retired. It was an extremely interesting group to be involved with, as the pilot members were all either senior test pilots from the major manufacturers and authorities or chief technical pilots from the major airlines, plus we had a lot of very good engineering and research guys as well. The official output is “Aerospace Recommended Practices” but bureaucratic inertia and commercial pressures meant, as always with standardisation activity, that it actually reflected the past while trying to address the future. Remember also the two rules about standardising things: “the great thing about having standards is that there are so many from which to choose” ; and “the BEST is the enemy of the merely GOOD” !

In reality by far the most valuable aspect was the informal discussions, as for example Boeing and Airbus test pilots could get “off the record” criticism and comment on their products from people they respected, and feed that back up the chain in a way that wouldn’t have otherwise been politically acceptable. However on many occasions of course there were “agreements to disagree” after debates that took place more in the bar afterwards than in the committee sessions – it was a very social group! The requirement that you had to be an active pilot to vote was important in keeping things fresh but I think the economic squeeze has reduced industry willingness to release people for such activities. A great pity really. Anyway, I’ll have to try and see if there’s an ARP which refers to positioning of radio transmit switches!

pax britanica

6th Dec 2010, 17:04

As well as commenting on WHBN s question about loads to Eastern Europe I wanted to say what a great thread this has been. I started flying as pax in 71 and made full use of fathers BEA/BA concessions which treated me as a child until age 26 (on reaching age 26 I married a Speedbird London radio op so the concessions continued)

Flew a lot on all BA Trident marks as pax thought they were great although on a trip to Rome with a friend who was a BOAC SO or junior FO on 707s he said he was never that good passenger especially flying backwards.

Tridents took me safely all around Europe and on my honeymoon and back so great affection for them. In fact the return from there was a very rare landing on 05R wooden approach light poles and all into a freezing and snowy Heathrow after a fascinating approach from ‘overhead the field’ which gave me my best ever view of my home airport.

Anyway back to Eastern Europe, I don’t think low load factors were confined to Eastern Europe –because I travelled sub load a lot I got quite adept at finding which flights were less busy. Some seemed to be virtually positioning flights to operate a peak hour sector back to LHR –mid mornings or afternoons to Amsterdam come to mind. As to Eastern Europe (proper Eastern Europe in those days too with soldiers and guard dogs on the ramp) I made a couple of trips there in 70s Budapest was one I think and that was a sort of Tue Thu Friday affair and as I recall was fairly busy but a trip back from Prague seemed to have about three people in addition to a BA football team I was a ringer for and of course we were all subload. Lot of fussing around by the crew on weight and balance issues on that trip –everyone forward of the wing I think.

A noisy beast on the outside but a good looking plane and I believe very fast-I recall one trip back from Rome as we smoothly passed a BOAC VC10 a few thousand feet below; the Captain ( this would have been pre BA) pointing out that we were easily overtaking the other iconic Brit jet. I also went to Stockholm several times on Tridents and they were markedly quicker than the Scandi DC9s over that sector but I don’t suppose saving 10-15 mins on even the longer short haul sectors made much sense economically.

Enjoyed all the postings here and it is so nice that PPrune allows those of us not Crew or ex Crew or Airline staff to enjoy such fascinating discussions.

ChristiaanJ

6th Dec 2010, 17:13

slast,
Ever met André Turcat?
I've met him a few times, never got to discuss the subject.

But reading his book ("Essais et Batailles"), he too really 'pushed' for more readable instruments, more 'ergonomic' controls (not sure the word was invented yet), and better panel lay-outs.

CJ

ChristiaanJ

6th Dec 2010, 17:21

For all you Trident aficionados passing near to heathrow - BA has an excellent museum 2 mins walk from hatton cross tube station.Address? Link? Contact details?
May pass that way sometime in the not too distant future (I hope), and would be livid ending up in front of a closed door.
And yes, I'll remember to bring the biccies.

CJ

slast

6th Dec 2010, 17:42

ChristiaanJ,
not really. I believe he was a guest at the first IFALPA Conference I attended which was organised at very short notice by SNPL aboard a ship (the Mermoz") but I was way junior too on the BALPA team to get to talk to someone like that. Brian Trubshaw's mother lived half a mile from me when I was a kid in South Wales though!

blind pew

7th Dec 2010, 19:42

links for the Museum
email link is on the link below.
British Airways - Heritage collection (http://www.britishairways.com/travel/museum-collection/public/en_gb)
- web address through BA page.
One of their staff of volunteers was present at the first ever departure from LHR.

ChristiaanJ

7th Dec 2010, 20:57

Thanks!
Link didn't work, but for anybody interested,this one should.
BA museum collection (http://www.britishairways.com/travel/museum-collection/public/en_gb)

CJ

Edit, no, it doesn't work either, if you use an ad-blocker.
Copy and paste the URL:
"http://www.britishairways.com/travel/museum-collection/public/en_gb"

ITman

8th Dec 2010, 04:37

Can you advise where the Trident cockpit is located, I seem to remember it was supposed to be located near a public house near the south side of Farnborough airport..?

Thanks

slast

8th Dec 2010, 11:00

typically it was the OCCUPANTS of a Trident cockpit who were to be found near pubs in the vicinity of airports.......

petermcleland

8th Dec 2010, 13:28

Can you advise where the Trident cockpit is located, I seem to remember it was supposed to be located near a public house near the south side of Farnborough airport..?

Zulu Kilo is at the Manchester airport park and the cockpit is in excellent shape...Here is a shot taken a couple of years ago of me in my old seat!...
http://www.petermcleland.com/ZK/znow.jpg

Old and Horrified

8th Dec 2010, 16:01

For all you Trident fans, while clearing out my office I rediscovered an interesting article in an old Flight magazine. In the April 8 1971 issue there is quite a long article about bringing the Trident 3B into service and also one about how they are built. I have checked and the edition is available on Flight's archive.

ChristiaanJ

8th Dec 2010, 16:27

ITman,
I think the one you're thinking of is
G-AVFH HS121 Trident 2E - Forward Fuselage
at the de Havilland Aircraft Heritage Centre.

petermcleland

8th Dec 2010, 16:43

Don't know if this will work here but I'll try it:-

http://www.petermcleland.com/misc/TridentCockpit.gif

It is a comparison of the real thing and David Maltby's Flight Sim model.

ChristiaanJ

8th Dec 2010, 17:44

Peter,
That's great.
You really have to look closely for the differences (apart from the missing PVDs in the original pics, of course).

CJ

slast

8th Dec 2010, 17:53

I'm missing something here - who is David Maltby and what/where is the model? Both pics look pretty real to me!

petermcleland

8th Dec 2010, 17:53

Peter,
That's great.
You really have to look closely for the differences (apart from the missing PVDs in the original pics, of course).

Christiaan,

The original PVDs are there if you look closely...The black rubber surrounds on the real thing used to sag quite a lot and the slot through which to view the "Barber's Pole" closed up a bit. However, when you sat in the seat the scrolling of the pole to left or right was clearly visible.

petermcleland

8th Dec 2010, 18:00

Slast the model is the one built for Microsoft's Flight Simulator by David Maltby. It is an extremely accurate simulation which will even do an autoland with full "Kick off Drift" in Fog. The other picture is the real thing. Both are the Trident 3 with boost engine.

Here is a YouTube video I made of a turnround using this model:-

YouTube - TridentTurnround.mp4 (http://www.youtube.com/watch?v=yu_FBY8ZU_c)

It has sound.

Helen49

8th Dec 2010, 19:06

Thank you chaps for the fascinating insights. Very interesting and enjoyable.
H49

ChristiaanJ

8th Dec 2010, 20:24

Christiaan,
The original PVDs are there if you look closely...The black rubber surrounds on the real thing used to sag quite a lot and the slot through which to view the "Barber's Pole" closed up a bit. However, when you sat in the seat the scrolling of the pole to left or right was clearly visible.Thanks, Peter!
I had the impression they'd been removed.

Comment from an ancient (very)... I always thought the PVD was an interesting idea at the time, much like the 'tunnel' displays, and the HUD, and MicroVision, none of which really were adopted in the end.

(The 737NG does seem to have a HUD as standard, but I don't know how much it's used.
We had a very simply HUD for runway guidance on some of the early Airbuses, but that too 'didn't make it').

CJ

DozyWannabe

8th Dec 2010, 21:34

Slast the model is the one built for Microsoft's Flight Simulator by David Maltby. It is an extremely accurate simulation which will even do an autoland with full "Kick off Drift" in Fog. The other picture is the real thing. Both are the Trident 3 with boost engine.

So I have to ask, how does the virtual Gripper compare (other than the fact that you have to be your own First and Second Officer ;))?

Tom355uk

8th Dec 2010, 21:48

So I have to ask, how does the virtual Gripper compare

Well, I've never been fortunate enough to even see a Trident in the flesh, but I have used Flight Simulator for many years and I have to say that David Maltby's Trident is the best aircraft I have ever used in Flight Sim, including payware aircraft costing in excess of £40.00. The level of detail and functionality is simply breathtaking, and as Mr McCleland mentioned (I believe he assisted in its development, hope I'm not wrong about that) the autoland with kick off drift is amazing, even with 20 kt crosswinds and dense fog.

As an aside, his BAC 1-11 and VC10 aircraft are equally as amazing. The man deserves the PC equivalent of an Oscar!!!

:ok:

Tom

Prober

8th Dec 2010, 22:36

Mention of the introduction of the T3 sparks memories. The fact that the engine was ‘plastic’ gave rise to great incredulity. The first few months in service however, saw a concrete block because it had not yet proved itself. When in service, it required (IIRC) a min of 900 kgs of fuel in the centre tank. The engine was shut down on reaching 3,000ft, by pressing the fail light, often by P2’s left foot! P3 was always kept busy when taxying out at LHR because any intersection T/O would require a YES/NO or a revision of figures. When in the R/H seat, I had a flight to ZRH with a particularly fuel conscious management pilot (TW). On arrival, he asked for our estimated T/O weight and this required the boost engine, so the extra 900 kgs were duly loaded. When the papers came, we were 5 or 600 kgs over the ‘No Boost Wt’. This, of course, was caused by the extra 900 kgs. Much cursing and grumbling ensued, all the way back home and his calculator was read hot working out just how much that had cost the company (and, of course, it was all our fault).
Prober

411A

9th Dec 2010, 00:56

Historical note...

PVD's were used (to the best of my knowledge) on only one civil American type, a Gulfstream One aircraft, owned and flown at the time by the radio and television personality...Arthur Godfrey.
With this aircraft, CATIIIA hand flown approaches were FAA approved, circa 1960.
The PVD's were certified and provided by the Collins Radio Corporation.

Having used the PVD in TriStar equipment (ex-BA aircraft)...they worked to perfection.

Full marks for the designers of the HS.121 Trident aircraft...they provided CATIII autoland when others couldn't/would't/didn't.
A superb achievement.

Dan Winterland

9th Dec 2010, 01:07

Some of the 744s I used to fly had PVDs. Airbus has a PVI (for indicator) as an option.

ITman

9th Dec 2010, 04:26

Thanks for the information ChristiannJ and Petermcleland I have now found the Farnbourough location:

The nose section of Trident three G-AWZI is located
at the Farnborough Air Sciences Trust (FAST) museum,
Farnborough airport. The museum is open every weekend
and bank holidays from 10:00 – 16:00 and entrance is FREE.
Address: Farnborough Air Sciences Trust Museum
85 Farnborough Road
Farnborough
Hampshire
GU14 6TF
Telephone: 01252-375050
Website: Farnborough Airsciences Trust homepage (http://www.airsciences.org.uk).

It is worth a look at their website many interesting items there....

Hobo

9th Dec 2010, 05:06

rogerbucks

9th Dec 2010, 08:02

A few years ago a 'flew' Andy Mattick's Trident 3 sim; He had a purpose-built barn for the beast, and I remember doing night touch & go's at Gatwick (no day visuals were available).

As I recall, you did not attempt to flare for landing (this inevitably resulted in a stall), but flew the aircraft straight onto the deck. The sim was somewhere near Tatsfield- lost his number, so I don't know whether it's still operational.

petermcleland

9th Dec 2010, 10:32

Prober - re the boost fuel - I stand to be corrected, but IIRC the fuel load was calculated in the normal way and 900KG min (ie it wasn't an extra 900kg) was loaded in the centre tank as that was the only tank that fed the boost (or an imbalance would result if it was fed from a wing tank). What was left was used in the passing FL100 fuel balancing process.

The T2 had a fin tank (700kg??) which drained into the centre tank - there was a speed limit (300kts??) until it had been used - also the T2 had water injection as an option on take off. This enhanced performance as long as you didn't want to climb, accelerate and turn at the same time. I remember a few occasions at Naples climbing into an inversion, turning and automatically levelling out.

The original Trident had 'pitch pvds' to the outboard of P1 & P2.

David Maltby's sim looks very close to the real thing - with the significant ommission of the pen holders under the coaming and chart holders below the DV window - both vital + (the scrap of card on the coaming with the flight number on it!)

Hobo, on that last point (the vital data card) David improved on that by mounting it over on the left as a grey card that could have the numbers written in chinagraph. When you load the aircraft and climb aboard the card is blank, however one click on the card fills it with the relevant figures for your weight at the time. In the air, on final approach, another click fills in the Vref. I think that card is visible in my YouTube video previously pointed to.

BTW...as someone mentioned, I had a very small part in its development but only very tiny points about things like the drift shutter operation and how the handbrake two sets of gauges worked etc. He did all the modelling and programmed the flight characteristics which are extremely realistic compared to the real thing. I wrote the Autoland Tutorial that can be downloaded with it and supplied some files that set up various training flights from Heathrow, culminating in a full Cat IIIb approach with very near minimum conditions. The other really amazing thing about it is the fact that it is Free!

You can probably judge just how realistic the Cat III is by glancing at these screenshots:-

FSScreenshots.com Forum - Viewing topic #5514 - Anyone for CAT III... (http://forum.fsscreenshots.com/dcboard.php?az=show_topic&forum=2&topic_id=5514&mode=full&page)

keyole

9th Dec 2010, 12:05

Hi, very interesting thread.
There used to be a guy named Andy Matocks who had a fully functionaling ex BA Trident 3 set up at his farm. It used to be about 100 quid for 2 hours. The sim was located near to Biggin Hill airport. I'm afraid I don't have any contact information now, but a bit of 'googling' around or a trip to Biggin Hill would probably find Andy and his sim.
rgds Bob.
ps I seem to remember reading somewhere that information regarding the Papa India accident in 1972 was classified for 50 years. I've read the accident report, but I'm curious about what mustn't be released for 50 years. Anyone got any ideas? Cheers.

Craggenmore

9th Dec 2010, 14:46

Found this going through some old pics. Shame I can't get the scan clearer!

http://img230.imageshack.us/img230/8763/familytrident.jpg (http://img230.imageshack.us/i/familytrident.jpg/)

avionic type

9th Dec 2010, 19:01

Thank you all for bringing back long forgotten memories of the Trident Auto Pilot system I was a avionic mech who helped to de-snag all the defects in the central area at LHR crawling under the flt deck floor to the "Electrics bay"to change the triplex system of pitch,roll,yaw , and autothrottle computers which were situated there plus that blasted signal generator that was housed there as well without which we would never have be able fault find and recertify the Autoland . it had its faults as a system ie it had mechanical switching as electronic switching was not available at the time and these used to stick and that channel was "thrown off " by the the other channels ,but from the late 60s to the end of the Tridents life it did 1000s of Autolands safely and may be did not repay the huge amount of the costs of development but it cut down huge diversion costs in bad weather But it was the first and the A.R.B. laid down very hard demands to reach its goals
it could all be summed up by the remarks the passengers said which were "Did WE Land in this fog, how are we going to drive home ?":ok::ok::ok:

Aileron Drag

9th Dec 2010, 19:13

Does anyone else remember the trouble one had starting the T3 boost? I seem to remember having to open the rpm on number 2 at a very carefully judged rate to get the damned thing to light-up. Too fast on the rpm increase and it would stall; too slow and it would overtemp, resulting in flames gushing out of the tail-pipe.

There were Boost-Engine-Gurus, who could always start the blasted thing first time. And when you switched the thing off (at 9,500 feet?), the average disgusting Gripper Mark 3 would start to descend! The T3 was absolutely and indisputably the second-worst aircraft I've flown. The worst was the Piper Tomahawk, but the revolting T3 wasn't far behind.

The T1 was a nice aeroplane; the T2 was a sports version. The Trident 1E was the turbocharged edition.

I'm sorry for the poor souls of my generation who were condemned to a decade flying the Trident 3. They deserve a medal. :)

AD

WHBM

9th Dec 2010, 20:48

I remember doing night touch & go's at Gatwick (no day visuals were available).Unfortunately the Trident never operated out of Gatwick.

As I recall, you did not attempt to flare for landing (this inevitably resulted in a stall), but flew the aircraft straight onto the deck.You mean like a PA-28R with the Hershey bar wings ? :)

Trident Sim

9th Dec 2010, 21:33

WHBM

Unfortunately the Trident never operated out of Gatwick.

Actually it did, albeit on rare occasions.

Although as far as I’m aware there was never a permanent Trident base at LGW, it was not unknown for an aircraft and crew to be based temporarily at LGW, to cover aircraft shortages or unserviceability there.

Twice in the 1980's I did just that, being based at a LGW hotel for a week, and operating to FRA and DUS.

Regards

Trident Sim

WHBM

9th Dec 2010, 21:50

Indeed, I should have been more precise, and have said that there was not a Trident base or schedule at Gatwick.

I think the only London bases were Heathrow ....... and Stansted (that should be good for a few more posts :) ).

avionic type

9th Dec 2010, 22:19

I'll talk to tristar 500 and ask him to give you the gen, he used to be good at starting boost engines at 4am in the morning on ramp checks.:ugh::ugh:

petermcleland

10th Dec 2010, 09:58

I've just been reminded of a Video that an ex BA crew friend made of the Trident Autoland in Flight Sim...It makes some use of the "Virtual Cockpit" as well as the 2D Panel. It runs for about 4 minutes and is best viewed when clicked up to HD 1080 and "Big Screen". It has sound:-

Ian's video of Autoland:-

YouTube - Autoland Cat IIIb (http://www.youtube.com/watch?v=gB_NvGeEFvI)

Wookey

10th Dec 2010, 12:23

Just why was the Trident a three pilot flight deck when surely most short haul aircraft of the era had become two crew operations?

slast

10th Dec 2010, 12:49

Just why was the Trident a three pilot flight deck when surely most short haul aircraft of the era had become two crew operations?
The two pilot crew aircraft up to the early sixties were propeller driven types (piston or turboprop) and hence much slower and operated at lower altitude and so were less complex. There were no two crew civil transport jet types at that time as far as I recall. Initial 737 development started about 1964 with delivery '68 I think, the first DC9 was delivered in 1965. Crew complement and associated costs did not become a major issue until the 70s.

petermcleland

10th Dec 2010, 13:12

Just why was the Trident a three pilot flight deck when surely most short haul aircraft of the era had become two crew operations?

The Super 1-11 was two pilot crew but I think the HARCO helping automated route flying was part of the deal to get it accepted as two pilot crew...Later, HARCO was removed and the workload went up again. I flew it as a First Officer with HARCO and I really liked it...However, I got my command back on the three pilot Merchantman/Vanguard and then onto the three pilot Trident and I count myself very lucky to have been a Captain on three pilot crewed aircraft. As a First Officer I preferred two crew but as a Captain I much preferred three crew, especially with the excellent Trident First Officers!:)

slast

10th Dec 2010, 13:21

Sorry, yes I forgot the 1-11, that was first delivered in January '65 so didn't pre-date the Gripper. The other shorthaul jets of the era included the Comet and Caravelle which were both 3-crew.

tristar 500

10th Dec 2010, 14:45

As avionic type haas quoted me as a Boost engine wizz!! I should point out that the biggest problem we had with them was lack of use, resulting in the fuel draining back to the centre fuel tank. This required the fuel system to be bled, my dodge was to bleed it but instead of doing a blow out to clear the residual fuel out of the system, was to replace the fuse & go straight for a start & most times that would fix the problem. I do recall that the run procedure was via the control switch on the overhead panel which could be selected to the rpm required, "eg" idle, climb & take off.

Wookey has commented on the crewing for the Trident. It was a very complicated aircraft & very advanced for it`s time. However in BEA (Best Ever Airline) we flew with a third pilot, other airlines like Northeast used a Flight Engineer. Their main task was monitering the systems as any failure had to be dealt with manually, "eg" generator or hydrualic failure.

JW411

10th Dec 2010, 15:56

I always thought that BEA was Back Every Afternoon.

Hobo

10th Dec 2010, 16:16

Better Eat Afterwards

ChristiaanJ

10th Dec 2010, 16:33

Let's try not to go too much O/T, 'coz this thread is too interesting.
I'm sure there's already another thread (JetBlast probably) with all those jokes.
Anyway, I always thought BEA stood for "Britain's Excuse for an Airline"....

I'm not biased, because I never had the occasion to fly either BEA or the Trident. I regret the latter....
I did fly on the 1-11, though. The very same one that went and got its feet wet off the end of the Corfu runway, one week after I flew on it...

CJ

Nick Thomas

10th Dec 2010, 16:50

I am enjoying reading this thread and have learnt a great deal about the Trident. So thank you all
I flew to Venice from LHR with BA in the summer of 1982. IIRC it was a Trident but am not sure which version. Were BA still flying all 3 versions in 1982?

Regards
Nick

WHBM

10th Dec 2010, 16:52

Just why was the Trident a three pilot flight deck when surely most short haul aircraft of the era had become two crew operations?
I think the first jets with more than two engines which was two crew were the 757/767, introduced some 18 years after the Trident. In fact when the Trident came along there weren't any 2-crew jets at all.

Among the twins, Caravelles were three crew, and even the first 737s had an option of a three crew flight deck, not sure if any were so configured. In the USA, the FAA had an arbitrary upper limit of 80,000 lbs (40 tons) for two-crew operations, which the Trident was well beyond. The first One-Elevens were marginally over this, and not sold in the USA, but it was redesigned as the One-Eleven 400 that came just inside the limit, as did the first short DC9-10s. The restriction was later relaxed when the DC9-30 and 737 came into prospect.

d71146

10th Dec 2010, 17:46

BEA= Back Every Afternoon
Well thats how it used to be in days of old.

Data Dad

10th Dec 2010, 17:58

At the risk of thread drift....

WHBM Wrote:

The first One-Elevens were marginally over this, and not sold in the USA, but it was redesigned as the One-Eleven 400 that came just inside the limit,

have to disagree - the intial One-Elevens were series 200 and MTOW was originally 73500lbs later 78500lbs (up to 79 pax) and was operated by Braniff, Mohawk and Aloha in the US. The later -400 was 92000lbs, up to 89pax.

Back to Tridents.... Spent a very enjoyable week or so in 1982 with British Airways as part of my ATCO training, 'flying' the Trident 3 Cockpit Procedures Trainer. That was until we broke it :eek: So we rounded off the time getting up at oh-dark hundred to use the full flight sim at Cranebank :) Also made a number of line-trips on the jumpseat - a late evening Bovingdon Snatch onto 10L was certainly interesting as was watching the flourish with which the crews operated the autopilot.

DD

Tom355uk

10th Dec 2010, 18:13

I think the first jets with more than two engines which was two crew were the 757/767,

AFAIK there has never been either a 757 or 767 with more than two engines....:} I believe the first two crew civil airliner with more than two engines would have been the MD11, closely followed by the 747-400.

Mt first ever trip was on a 1-11, operated by Maersk Air UK in BA Landor livery from BHX to BFS in 1995. Unfortunately, only being 10 years old at the time I didn't realise the significance of this beautiful machine. Would have asked for a flight deck visit if I had! I reckon we should sod the Euro noise regulations and bring back the old metal :cool:

avionic type

10th Dec 2010, 23:48

I see the old jokes are begining to come in over the initials B.E.A. etc but it was my airline and I was very happy to work there, I prefered the Trident 1 to the others and was happy to see the Auto pilot from when it started in 1964 as a very basic system to when it reach the system that was trusted to carry out fully automatic Cat3B/C blind landings with complete faith by all. It had 3 of everything 3 separate power supplies ,3 hydralic systems, pitch and roll computers, gyro units, servo units on each control surface so it was a complicated piece of kit
in fact it was 3 auto pilots working together and if 1 disagreed with the other 2 it was automaticlly disconected from the system and the other 2 carried on ,if they disagreed with each other the system disconnected itself and and the A/C reverted to manual flying but after a lot of work it was finally given the authorisation to do what it was designed to do. :ok::ok::ok:

ChristiaanJ

11th Dec 2010, 00:29

avionic type,

Myself, I was brought up on the "duplex monitored" principles used on Concorde (and earlier on the VC-10?).

Slightly more hardware, possibly, since each of the two computers contained a complete "duplicate", charged with monitoring the "command" side, and handing over to the other one, if "command" and "monitor" disagreed.

The two computers barely talked to each other (the standby one stayed synchronised, but "kept its mouth shut"), while a triplex system involved a lot more data being exchanged and compared between the computers, hence more and differently designed hardware.

I have no idea what really was the best solution..... espcially since not so soon afterwards we went to digital systems, where we were dealing with a whole new ballpark.

CJ

WHBM

11th Dec 2010, 10:42

AFAIK there has never been either a 757 or 767 with more than two engines....:} I believe the first two crew civil airliner with more than two engines would have been the MD11, closely followed by the 747-400.
Oh dear, what a cockup. A real victim of too quick cut-and-paste combined with Getawayitis from the office (note a posting time of 1752 on Friday evening !). I suddenly realised the error driving up the M4 Heathrow spur about 30 minutes later. Now I believe the first more than two engined jet with two crew was the BAe146, which does marginally fit the topic as it followed the Trident some years later down the assembly hall at Hatfield. Any parts of the Trident contributed to the 146 ? I believe its main gear design owes a lot to the Comet.

safetypee

11th Dec 2010, 21:03

Oh the years I have waited for this trivia question.
IIRC the ‘Q’ pot was the same in both aircraft, and possibly the same design as in the Comet (and even the Sea Vixen).
Greater contributions from the Trident were in the experience gained by the design team, the technical and operational certification, and the practical application of the airworthiness philosophies of triplex systems. These were major advances in modern airworthiness.
Lessons learnt from the Trident – the 146 was strong, well built, also like the 125. The 146 had sparkling field performance in comparison ;-)

The two crew certification of the BAe146 was ‘a first’ in that it had to follow precedence set by the BAC 1-11 and DC 9 types, particularly with the FAA – but they had failed to consider that a two crew, 4 eng aircraft, could exist.

Adverse Jaw

12th Dec 2010, 16:05

After the BEA/BOAC merger, the then L/Haul PLC attempted to preclude the transfer of S/H pilots by imposing an arbitrary experience limit of 4-eng jets only, quite overlooking the fact that Trident 3 was (sometimes) just that and so, a number of the unwashed got their hands on VC10 and B747.

Aileron Drag

12th Dec 2010, 17:18

Yes, AJ, and that was when things got interesting.

We flat-earthers had been taught that the 'OD' crowd were aliens. Their SOPs were odd. Everything about them was odd. The BEA people who migrated to VC10s & 747s were looked upon with awe; as though they were throwing themselves into enemy territory, never to be heard of again.

On the other side of the coin, the rule that new commands must be on short-haul meant we (on the Gripper) were flooded with newly promoted OD 'aliens'.

Guess what - they were great guys, and the barriers came tumbling down.

It's odd now to think how tribal British Airways was, in respect of flight-crew. Forced integration fostered mutual respect. And it started on the Gripper.

Shame the flight-deck / CC barriers still exist. (sorry Mods). :)

AD

Midland 331

12th Dec 2010, 18:06

Does anyone have anything nice to say about The Trident? The best praise I detect from this fascinating thread is mere polite neutrality. As befits well-mannered Nigels.

I'm guessing that it cruised happily at M0.88 or whatever, and I've read that it could descend impressively when called upon. But were any of the variants a vaguely fun stick and rudder machine? I suspect not the "3"

r

Aileron Drag

12th Dec 2010, 19:39

Midland 331 - no, not the '3'. The Trident 3 was a stretched T2, with 30-odd seats added. Same wings, same undercarriage, same engines. Ergo - it couldn't get off the ground.

So, they stuck a plastic engine in the tail which was either 'off' or 'full-on'. It couldn't be re-lit in the air. In an infamous incident a T3 lost an engine out of Madrid. I recall that this happened after the plastic engine was shut down. The aircraft returned to Madrid, but had to go around on short finals due a blocked runway.

Without the boost engine, the damned thing wouldn't climb engine-out! They flew around at zero feet trying to build up a little kinetic energy!

In short, the T3 was a nightmare. The wings started to crack eventually beacause the weight was too great. Ugh!

Does anyone have anything nice to say about The Trident?

Yes, the T1 & T2 were brilliant. The T1E was even better. I still get wobbly-knees at how fantastic the T1 & 2 were to fly.

It's the dreadful T3 that I'd prefer to forget! Fortunately, I escaped to the 'new' 757 fleet a few months after being press-ganged onto the '3'.

AD

Hobo

12th Dec 2010, 19:43

I had 14 years on the Trident, most of it on the T3. I wouldn't have missed it for anything - great aircraft, great routes and the best bunch of fellow pilots.

From the late 70's onwards, most of the time most people flew manual raw data approaches with manual throttle - just for the pleasure of it, and the level of expertise was second to none.

slast

12th Dec 2010, 19:53

Does anyone have anything nice to say about The Trident?

I think it was the most technically advanced aircraft of its era. It had (IMHO) excellent flying qualities throughout most of the flight envelope but was marred by inadequate performance which was the result of all the b****ing about done by BEA’s management at the very beginning to reduce the basic design requirement. That resulted in it being very difficult to stretch and improve commercially. All the “stretching” done from the 1C to the 3B really just put it back to where it should have been in the first place and exhausted the potential. A T3 with more powerful engines from day 1 could have been stretched to a 200 seater and would have been a real world-beater.

Two examples of its good points. I flew the Trident from early T1 introduction to the point where it started being replaced by the 757 - BA was the launch customer for the 757 along with Eastern. I was lucky enough to be involved on the BA/BALPA 757 liaison team, so we saw a lot of the development work from the inside and got to know a lot of the Boeing test pilots and engineers.

When I managed to get qualified on the 757 fairly soon after it was introduced, there was a conversation with some of the Boeing guys (maybe together with Peter Harper who was the BALPA Tech Committee chairman at the time and also qualified on it) along the lines of “how do you like your new ship?” To which the reply was while we LOVED the power and performance, we weren’t very impressed by the flying qualities which seemed like a step backwards. A Trident handled like a sports car in terms of control response especially in roll, it also had very little trim change with speed and configuration and very light control forces. With a 757 if you took the wheel and rotated it quickly it from one side to the other and back to neutral, the aircraft would just sort of “turn round and look at you” as if to say “oh, are you talking to me?”. Similarly, with an asymmetric approach, every time you changed the power, you had to re-trim in all three axes.

Maybe these comments were slightly exaggerated for effect, but the Boeing guys were astonished and said that we ex-Trident pilots were the only people who had commented negatively about the 757’s flying qualities. But the only other people who had been exposed to it at that time were accustomed to other Boeing and/or Douglas products and measuring from a different "norm".

Another early experience was when I flew a 757 service which replaced the Trident on either Brussels or Amsterdam, and we had thick fog. I had to delay departure for quite a while till the RVR improved as the lowest 757 takeoff RVR was higher than that of the Trident with its PVDs. It was caustically noted by some of our regular passengers the old T1s that were then being broken up had a better all-weather capability than their shiny new replacements!

Prober

12th Dec 2010, 22:43

Yes, they do. We ex Gripper chaps are professional aviators and we do not go all gooey over our aircraft. We flew and enjoyed ourselves without fuss. (Tongue in cheek, in case.) I went from “Guardsvan” to Tridents as F/O, back to Merchantman as LHS and then back to Tridents. I had 2 years in each of the Trident seats and enjoyed it immensely. It really was a marvelous aeroplane and going back to the VC9 seemed like going back to the stone age. I remember Slast very well but did not have nearly such a distinguished Trident career as he did, so I cannot comment on the background of much that went on. I remember well sitting on the edge of my seat during the early days of autoland. There was an alarming, but fortunately rare, likelihood that it would either try a reverse acquire or do something equaling entertaining at the flare. I used to wish that all the dolls eyes and other A/L indications could be grouped together in a ladder, to advance progressively to (hopefully) give a LAND decision. I, too, converted to the 75 and there was the ASA!! And I was dumbstruck at climbing to FL410 in 20 mins – on the Gripper, one applied “contingency power” (an extra 200 rpm!) when the rate of climb fell to 300fpm. Getting to cruise could easily take 30 mins or more and yes, the T2 had a Fin tank which would be empty before TOC. But to answer the question – YES, it was brilliant and great fun to fly. Only the 767 has anything like its controls response – and that definitely in ROLL only.
I remember the report on the 2 eng go around for the T3 at MAD (the R/W layout had been sitting there just waiting for this to happen). The average ROC was 200 FPM and the ATC reported that when it disappeared behind the hills they did not expect to see it reappear. I never discovered why the Boost was never cleared for an inflight start – I bet that crew wished it had!
Prober

Hobo

13th Dec 2010, 05:23

Subsequent to the MAD incident, a procedure was introduced where the boost could be started in flight. It involved a very lengthy procedure with CB's being pulled to make it think it was on the ground and an extremely small relight speed window (IIRC). The Chinese insisted on this from the start on their T3's.

With Gil Gray, I took one of the T3's to Hatfield for sorting out the wing cracks. While we were waiting for the transport back to LHR John Cunningham showed us round one of the Chinese examples. All the decals were in Chinese and the flight deck extended back to the fwd door, where the fwd toilet usually was, to make space for a huge desk portside rear, where the 'Commondant' of the aircraft sat - inter alia making sure the crew didn't defect to the West.

Adverse Jaw

13th Dec 2010, 08:54

I too spent 9 happy years on the Trident mainly Threes and don't recognise some of the adverse comments made. As conveyed so well by Steve, the problems of lack of thrust were of BEA's making - but entering a descent after boost engine shutdown - absolute tosh. As for its flying qualities they were superb - and I've seen it up to the high subsonics, with no signs of mach buffet or need for artificial devices. By contrast, the Tristar required the terrifying Recovery Speed Brake and the DC10 hit a wall above M.85 needing bank angle limitation to obviate buffet during cruise.
How good to see Pete and Steve going strong though Pete barely recognisable without pipe.

slast

13th Dec 2010, 09:30

I think one of the reasons that the "it wouldn't climb with an engine out" story came so common was actually that the aircraft obviously DID meet the requirement to be able to climb - but without much to spare most of the time! Most people (fortunately!) don't ever experience how low a gradient and how little clearance is actually required to meet the performance requirements - it is very little indeed!

Virtually all our experience is gained with all engines operating, and in circumstances where we are well within the limits of the performance envelope. In normal operation the Gripper unfortunately seemed to sit a lot closer to the edges of the envelope than most other types do. Fortunately at that time the ARB (predecessors to the CAA) used to require a sample of every fleet to be air tested each year to ensure that the overall performance was still typical of that demonstrated in initial certification. I suspect (I don't know) that's been jettisoned under JAA/FAA harmonisation of rules as the Americans certainly didn't like that idea, but I remember flying as P3 to Gordon Corps doing one of these recurrent air tests. (Gordon was CAA chief test pilot before joining Airbus in 1982, and a member of the SAE S-7 "what goes where" committee I referred to earlier (Post #117). One certainly realised how little climb capability was needed to meet the rules when seeing it demonstrated by someone like that - I was stunned by how precisely he could fly the aircraft straight off the ground when probably he hadn't been near one for over a year, and any "wobbles" away from the precise optimum speed would certainly affect the outcome.

slast

13th Dec 2010, 09:37

Anyone interested in hearing how BA internal politics and Trident reverse-in-flare landing nearly screwed up NASA's Air Safety Reporting System??

forget

13th Dec 2010, 09:59

Anyone interested in hearing how .........

Yes! :) ........... and any news on the inboard PTTs?

Hobo

13th Dec 2010, 11:52

I had 2 engine failures in my career, both on T3's. Both were on rotation and both when I happened to be handling pilot. On neither occasion was there any problem with climb rate, although one was GLA-LHR and the second LHR-GLA, so not particularly heavy. The controls felt a bit wishy washy compared to normal, but no problem.

The first was #2 in YZ in June '76, my logbook tells me. As I rotated there was a loud muffled bang and I felt the control column being pushed forward, immediately followed by it being pulled back, then returning to the trimmed position. I had to resist the forces quite strongly to keep the column where I wanted it to maintain attitude during the rotation.

The aircraft had had a history of yellow hydraulics problems on initial climb, so P1&P3 looked up to the hyd levers for the stuck valve light, as I said check the hydraulics as I felt the forces through the column. Nothing there, no yaw of course, I glanced at the engine instruments and saw the TGT of #2 off the clock. No fire, shut down and return, right hand visual circuit to 06.

The second in VF in Jan '80

(With PMc). #1 blew up on rotation, with an incredibly long and loud graunching sound - it sounded like, and felt through the controls, and I thought, the U/C had collapsed as I rotated. It felt to me like we were being 'held' on the ground by the collapsed oleos dragging along the runway, and I remember being slightly surprised to see a positive rate of climb as the rotation progressed and we eventually got airborne. PMc thought we had hit a vehicle. Again no climb problems.

I remember thinking after the second one, this was the classic scenario, just what we do in the Sim, an engine failing on rotation, yet neither of these was anything like I had experienced in 12 years on simulator checks to date. Because of what else was happening, and the visual, tactile and aural clues we were getting, on both occasions, with no fire bell, not one crew member's first thought was that we were experiencing an engine failure - although it was very quickly picked up.

Still got some melted fan blades from both incidents.

Adverse Jaw

13th Dec 2010, 12:40

Yes, Go on Steve!

Wookey

13th Dec 2010, 15:26

Fascinating to read these insights on the Trident from you guys who do the pedalling.
From a pax point of view I always enjoyed flying in the Trident (moreso than the S1-11), always comfortable and seemed to handle turbulence well and of course those were the days when full service airline meant just that!!
On my earlier question about the 3 pilot crew, who decide which crew member would be P2 or P3? Could P3 count his hours sitting in the middle seat watching the guages.? Did P2 and P3 change seats with each sector?

TRC

13th Dec 2010, 15:33

Not wanting to get in the way of slast's story, but I have a question about the Trident.

I flew as SLF on this type at least a couple of dozen times, and every time I was in a seat that had a view of the wing I noticed that the aileron was constantly moving. Not in a random fashion, but systematically up and down a few degrees pausing for a second or so at the end of each move, with an attendant roll back and forth. The roll was most noticeable if the sun was casting shadows inside the cabin which moved up and down - it was a bit like being on a ship.

I saw this often enough for it to be a norm rather than a particular aircraft with a lazy autopilot.

Anyone else notice this?

slast

13th Dec 2010, 15:47

Wookey,
The Gripper in BA service was unusual in that all the First Officers were licensed in both the copilot and flight engineer seats. Typically (unless there was a training or other requirement for one pilot to be in a particular seat) the two F/Os would toss a coin to decide who sat where for the first sector and then changed seats each leg. The P3 was fully integrated into the overall flying tasks rather than "watching the gauges", and not licensed as a Flight Engineer who could carry out additional engineering tasks on turnarounds. So time as P3 was counted fully as "Copilot" hours.

With experienced crews and suitable conditions, many captains operated a leg and leg basis that meant that on a three sector day which was pretty common everyone got a takeoff and a landing in the course of the day.

Wookey

13th Dec 2010, 15:55

slast

Thanks for the explanation

TRC

I never really noticed this and I probably flew several times a month most on Tridents for maybe 10 years. But then maybe I was just enjoying the full service too much to notice !! Be interesting to hear if the 'pros' have any insight into this

Hobo

13th Dec 2010, 16:08

TRC Unlike some types (eg 737) you couldn't see the wings from the flight deck windows. I was never aware of what you describe.

...regarding the climb performance, the standing joke was:-

Scottish -".... can you make 300 or above by the Cross*?"

Trident - " Not even Northbound."

* Dean Cross - VOR about 80 nms South of GLA/EDI

petermcleland

13th Dec 2010, 16:15

TRC

13th Dec 2010, 16:30

I never really noticed this ........
I was never aware of what you describe

Well, it wasn't much of a roll - it didn't spill your your drink... You could just see the t/e of the aileron appearing and disappearing relative to the t/e of the wing. The moving shadow was a little more obvious when there was one.

It always fascinated me - maybe I should have taken a better book..

slast

13th Dec 2010, 17:01

It was a dark and stormy night……
Actually we’ll start a bit earlier. Remember the sequence post WW2 – the old Imperial Airways was relaunched by the new Labour government as BOAC and BEA. I think that given the chance some of the more radical thinkers went to develop BEA’s new high density European network while the traditionalists stayed with the old Imperial “flag carrier” tasks of BOAC. In flight ops certainly BEA had a lot of challenges including a high exposure to poor visibility ops and was prepared to develop new thinking on a variety of issues including training flight deck procedures and so on.

BEA’s management seemed to take the view that if existing solutions don’t fix a problem, you need to find a new solution even if goes against tradition. BOAC’s seemed to be that its practices were the best there could be, and required extremely high individual performance: in general, safety problems were due to failure to meet those standards, and that could be fixed by dealing with individuals by disciplinary or other means. There were thus two very different philosophies about how to achieve the best safety results in the two corporations.

So when the decision was taken to create BA by bringing them back under a single roof, but retaining “autonomous operating divisions”, what had previously been a legitimate rivalry between two separate organisations became entrenched internal warfare. This led to weird situations and turf wars where groups which were supposed to be on the same side were actually allied with their nominal “enemies”, e.g. in discussions with the pilots it wasn’t so much “BA management vs BALPA for BA pilots” as “Longhaul pilots and management” vs “shorthaul pilots and management” with leaks and “conspiracies” galore, especially before the privatisation of BA forced a proper merger to take place (eventually).

One of BA’s best aspects has always been having an independent Safety Branch, independent of departmental managements and reporting directly to the Board and giving the Board clear overall responsibility for corporate safety. The Air Safety Adviser therefore carries a lot of “clout” which is good in many ways - but can have drawbacks.

As I said earlier, BEA was never averse to making radical changes if it thought them necessary and the need to fix the low visibility ops problems led to the autoland programme which among other things required validation of test landings. This in turn led to the development of much more advanced flight recorders and in particular the Quick Access Recorder, which could be analysed after every flight.

There was also a difference in attitude between the pilots’ representatives in BALPA on the technical/safety side and those on the industrial side, with again the “techies” tending to be more open to changes while the industrial guys were very suspicious of them especially when initiated by management. Anyway, over the years collectively BALPA, BA and the CAA developed understandings about the use of flight recorders for ACCIDENT investigation, about confidential “no blame” incident reporting which basically led the world. This then led to an agreement with BA about the use of FDRs for INCIDENT analysis, and which has eventually led toroutine use for preventive measures in QAR programmes etc.

It was basically BALPA and BA which did the ground-breaking work on all that. So all this was followed with interest elsewhere, especially by NASA who were keen to introduce similar confidential anonymous reporting and so forth in the US, against a lot of opposition from many in ALPA, as well as some voices in the FAA and DOT, who were concerned about the legal implications etc. So how BA’s agreement worked was seen as setting some pretty important precedents.

So much for the background - now to the “dark and stormy night”…... and a T3 is making an approach at a Spanish coastal airport. There is a big T-storm approaching the far end of the runway. The Trident NORMAL landing procedure as noted earlier in this thread, is to close the throttles and select reverse idle (pod engines obviously) IN THE FLARE. This was actioned by the P2 as non-handling pilot, the handling pilot P1 having both hands on the yoke. Optionally one could then select FULL reverse while in the flare, and this was a very effective technique on short or wet runways as the Trident had pretty mediocre brakes. So the crew brief for this technique, in the flare the call is “Power off and full reverse”. The P2 closes the thrust levers and immediately pulls up the reverser levers, the buckets deploy and the pod engines never spool down but increase RPM from the approach value to close to full power for a few moments, then back to idle as the aircraft slows. The aircraft has rolled into a wall of water at touchdown and during the rollout the P3 notices that the antiskid stops working on the right gear. Roll onto the ramp, the rain is bucketing down and an engineer comes aboard to report that two tyres are burst and four are badly scalded.

Then all the lights go out in the region as the rainwater floods the area. So the a/c is on the ground for the night while some new tyres are shipped down. The crew write up on of the new Mandatory Occurrence forms for the burst tyre incident and return to base, and life goes on as normal.

About a month later the Captain gets a summons to see his manager, who has a “confidential” engineer’s analysis of the QAR, saying that (inter alia) the tyres were burst because “the pilots had not used the recommended landing technique of selecting reverse IDLE in the flare. In a sort of drumhead court-martial, the Captain is suspended and is required to do a base check before being allowed back on the line.

At this point the s*** hit the fan because they had effectively taken disciplinary action against an employee without complying with any of the requirements of their own disciplinary procedures. Not only that, the pilot involved happened to be one of the BALPA reps involved in developing the agreement on the use of FDRs for incident analysis, and the management have just busted every clause in it!

The whole event demonstrated why the agreement had all the clauses about getting ALL the information, and involving all parties including the crew members concerned, BEFORE reaching a conclusion as to what happened. They had just gone raw FDR > engineers interpretation > management > disciplinary action. (Of course the bare statement about not using the reverse IDLE was correct, unfortunately the trace does not contain the reverser position.)

So what was the politics behind it? One interpretation was it was an opportunity to make an example: “OK, if we can get a BALPA rep right at the start we’ll never have a problem using FDR info to prove pilots haven't complied with recommended procedures”. More likely in my view was that there had already been a major difference of view at top level about the company philosophy. The air safety adviser, was ex BOAC and seemed to believe that pilots who had incidents and had not followed recommended procedures to the letter should be disciplined. The ex BEA chief pilot I think took a much more nuanced view of the complexities of everyday operation and was actually reluctant to use disciplinary action per se. I suspect the chief pilot knew the engineer’s analysis was automatically sent to the board’s Air Safety adviser, and decided to pre-empt any criticism (“here’s another of your pilots screwing up, what are you going to do about it?”) and clear his own yard-arm by just getting the pilot re-confirmed as competent, so he could tell the Air Safety head where to go. But it didn’t work out quite like that because he was out on a limb on both the actual event and the procedures.

Internally the upshot was a letter of apology from the Deputy Flight Ops Director to the Captain concerned (via BALPA!) and an acknowledgement that the whole thing had been grossly mishandled, to the great embarrassment of the company, followed shortly after by some changes of management pilots. However, it nearly caused the whole agreement to come off the rails, just at the time when NASA was trying to convince US ALPA that airlines and authorities could be trusted to use safety data responsibly and not use it to screw individuals who took part. When Charlie Billings who was running a lot of that activity heard about what had happened, he was afraid that word would soon get out in the wider industry. I thought he was going to have a heart attack, as the BA/BALPA agreement was being held up as a global example of how this stuff could be made to work, and here was the first example of what actually happened! Fortunately we damped it down and things proceeded smoothly in the long run, but it could easily have turned out differently.

u118075

13th Dec 2010, 18:21

The Gripper in BA service was unusual in that all the First Officers were licensed in both the copilot and flight engineer seats. Typically (unless there was a training or other requirement for one pilot to be in a particular seat) the two F/Os would toss a coin to decide who sat where for the first sector and then changed seats each leg. The P3 was fully integrated into the overall flying tasks rather than "watching the gauges", and not licensed as a Flight Engineer who could carry out additional engineering tasks on turnarounds. So time as P3 was counted fully as "Copilot" hours.

With experienced crews and suitable conditions, many captains operated a leg and leg basis that meant that on a three sector day which was pretty common everyone got a takeoff and a landing in the course of the day. You mean like this!

http://i1185.photobucket.com/albums/z357/u118075/Tridentcockpit.jpg

Adverse Jaw

14th Dec 2010, 09:05

Steve, your post reminds us that a lasting legacy of the Trident was that on completion of the autoland proving trials, the company found themselves with a redudent 64 channel data recorder on the entire fleet. This data could have been used in a variety of ways, some of them harsh & disciplinarian. However, BEA and BALPA came up with the enlightened SESMA programme which in my view is one of the greatest single contributors to air safety.
Then again Papa India, the main cause of which was the Tridents big design flaw - not incorporating flap & droop into a single lever, brought about the introduction of CVR

slast

14th Dec 2010, 09:20

AJ, agree completely.

Meikleour

14th Dec 2010, 09:53

Slast: really enjoyed your "stormy night " tale, but wasn`t that rather close to home......................

DozyWannabe

14th Dec 2010, 10:02

A Trident handled like a sports car in terms of control response especially in roll, it also had very little trim change with speed and configuration and very light control forces.

Or in other words "like a De Havilland" - to paraphrase "Cats-Eye" Cunningham... ;)

slast

14th Dec 2010, 10:32

Meikleour, I have no idea what you mean....! ;)

WHBM

14th Dec 2010, 11:05

Or in other words "like a De Havilland" - to paraphrase "Cats-Eye" Cunningham...
I believe that John Cunningham himself didn't like the feline nickname at all - although my only contact with him was a passing "Hello Mr Cunningham" when he opened the Biggin Hill show about 10 years ago.

411A

14th Dec 2010, 12:17

...Tristar required the terrifying Recovery Speed Brake

The only thing 'terrifying' about the Recovery Speed Brake was the UKCAA's insistance that one be fitted. There was no such requirement by the FAA, who by the way, originally certified the aircraft.
The UKCAA always was a bit obtuse in the certification department...:rolleyes:

DozyWannabe

14th Dec 2010, 13:16

I believe that John Cunningham himself didn't like the feline nickname at all.

Apologies in order - was paraphrasing from a book.

ChristiaanJ

14th Dec 2010, 13:43

I believe that John Cunningham himself didn't like the feline nickname at all.I remember the same, from reading "Night Fighter" (by C F Rawnsley and Robert Wright, great book btw).
To 'camouflage' the performance of the early airborne radar, the story was put about that his successes were due to "being able to see in the dark like a cat", hence "Cat's Eye Cunningham".
The book mentions too, that John heartily detested the nickname !

CJ

Dan Winterland

14th Dec 2010, 14:19

And to help perpetuate the myth, they were introduced to the press all munching on raw carrots. Allegedly (but not truley accrately) the beta kerotine aided night vision. This article helped perpetuate the myth that carrots helped you see in the dark. The joke carried as the Luftwaffe tried it as well after having read the article!

Wookey

15th Dec 2010, 10:03

....... and back to thread topic !!!!

Given the different performance carachteristics of the different variants, were the crew licenced on all three types in use with BEA/BA?
Secondly (assuming that they were) was the flight planning routine complicated by this factor, particularly T3 with it's 'fourth' engine?

Aileron Drag

15th Dec 2010, 10:53

Wookey - No, we were not qualified on all three types. You were on either the T1 and T2 (that is, qualified on both, and alternating according to your roster), or you were licenced on the T3 only.

Having said that, when I left my T1/T2 fleet and converted onto the T3, it was a pretty straightforward conversion.

Regarding flight planning, I think I remember correctly - the T1 fuel planning sheet (can anyone remember what we called it?) was printed on white paper, the T2 was on blue paper, and the T3 on pink. Have I remebered that correctly? Performance data was also on different coloured pages.

My memory is heading 180 Magnetic, I'm afraid.

AD

Hobo

15th Dec 2010, 11:08

From about 1980 onwards all crews were 'Tridextrous' and flew all 3 types.

Colours correct, it was called the P3LOG IIRC, it then became the KELOG, when Pete(?) Kimmens and Simon Edwards redesigned it.

Wookey

15th Dec 2010, 11:25

From about 1980 onwards all crews were 'Tridextrous' and flew all 3 types.

Hobo, what happened in 1980 to change things? Alternatively, prior to 1980 was the reason that T1/T2 were isolated from T3 just the fourth engine and performance, or something else?

Hobo

15th Dec 2010, 14:36

I think, although Steve might know for sure (?), that the reason was that from about 1975 there were no new NEP/DEP pilots coming into BA on the Trident, so by about 1980 the minimum co-pilot experience was 8-10 years or so, and the CAA, who had vetoed it before, were persuaded by BA, with this amount of experience, to approve the tridextrous route - economics presumably being the driver.

I don't think it was the 4th engine, all this did was give extra thrust for T/O and although its operation was complex, it was just another system. I think the main reason was the very different pitch attitude on approach. IIRC 7-9 degrees in a T1/2 and 3-4 degrees in a T3.

I had done 2 years on the T1/2 when the T3 came in. Initially it attracted more pay, so all the senior guys went on it. After a short while there was parity with the T1/2 so nobody wanted to go on it - it didn't go to the Eastern Med - so juniors were posted. After 7 more years on the T3 I became tridextrous, 1 sim session in the T1 sim, 3 sectors line training with two landings. IIRC you couldn't do 3 consecutive sim checks in the same sim, and there were no requirements for recency flying on the 3 types.

Meikleour

15th Dec 2010, 16:30

Hobo: The following licencing quirk may amuse some of the posters on here.

As Steve posted earlier, The Gripper was crewed by three pilots in BEA/BA but by two pilots + flight engineer in some other airlines.
Now, when BEAirtours started operating the B707-436 they had no qualified Flight Engineers on staff as required by the CAA. The company got approval to qualify their F/Os as P2 and as flight engineers. To get this approval, one had to have 2,000 hours flight time on 4 engined aircraft. This was mainly Viscount and Vanguard/Merchantman people but, believe it or not , the T3 qualified also as it had four engines!!
This, I recall, did not sit very well with a branch of BA that flew predominately long haul!

slast

15th Dec 2010, 17:57

I think Hobo's got it pretty well covered...! And wasn't the official term for the P3 IIRC was "SPO" - "Systems Panel Operator" ? as opposed to Flight Engineer.

Prober

15th Dec 2010, 21:37

The mists of time are starting to drift in, but I seem to remember that a general feeling at the time was that the T2 and T3 had more in common and the T1 should be its own fleet (if---if that was necessary at all). When "Tridextrosity" (??) was introduced, the view was that it had taken all those years for common sense to prevail.
Prober

blind pew

16th Dec 2010, 09:03

Adverse Jaw
I beg to differ on your comment re "design fault caused Papa India."

Cunningham's testimony at the inquiry stated that we operated the Trident contrary to HS's design philosophy.

This was to retain T/O flap until acceleration point. If this had been carried out than none of the premature droop retractions would have happened.

BEA noise abatement procedure was one of the most foolish procedures that I have ever carried out - except the Vmca at 300ft in the Baron over the English channel.

Very interesting history from SLAST.

The philosophies in BOAC were incredibly different to BEA, I was in the first group that "went across" - there was a movement to send us all back - started by some of the 707 training captains (ex National Service)as we were not up to BOAC standards.
Fortunately I was on the Iron Duck with mostly ex Hamble training captains who understood the deficiencies in BEA.

One point was that I had never used wx radar in my 6 yrs on the Trident!

I think the greatest shock for my first line training captain was when I asked if it was OK to descend and then whether he would mind if I disconnected the autopilot - both standard practices in BEA.

It took me around six months to "get into the grove" and accept that when I flew a sector I made ALL of the decisions - including declaring the only Mayday I made in my career.

slast

16th Dec 2010, 11:49

Cunningham's testimony at the inquiry stated that we operated the Trident contrary to HS's design philosophy.
BP, do you have a reference for this (I couldn't find it in the report but that doesn't have the verbatim statements.)

Hobo

16th Dec 2010, 12:07

I carried JC on the jump seat once in the mid 70's, returning from a conference, and he said the only thing he would have, in retrospect, changed on the Trident was to have the droop and flap on the same lever, with the last 'flap' setting being the droop. IIRC this was echoed in later editions of Handling the Big Jets by DPD.

After PI, there was a mechanical interlock put on the levers, so the droop lever couldn't be moved without the flap lever in the up position.

During the course of this flight, he said that HS couldn't get to the bottom of why the T3 usually gave a firmer landing, and was more difficult to grease on, than the T1/2. Even he said he couldn't guarantee the landing on a T3. Their best guess was that it was to do with the different 'rigger's angle of incidence' ie the way the wings were fixed relative to the fuselage, and the different height above the ground that that put the trailing edge of the flaps. The theory was, that this distance, on the T3, was so critical, that mm's meant the air being 'sucked' out with a venturi effect (firm) or not (greaser).

bp .... the deficiencies in BEA

Which were?

Wookey

16th Dec 2010, 15:36

Do the old rivalries linger on ?????

There have been a number of posts in this thread that have referred to the Trident's ability to cruise at high speed (Peter McLelland's reference to the mach meter in his photo etc.). I am curious as to whether the 'Gripper's' lack of climb performance was due to it being underpowered or due to lack of lift from the wing design and whether this translates into lower drag and higher cruise speed.

Adverse Jaw

16th Dec 2010, 16:08

BP

Just think about it - with a single lever, Droop could NOT be raised in lieu of flap.

Aileron Drag

16th Dec 2010, 17:25

You said,

'After PI, there was a mechanical interlock put on the levers, so the droop lever couldn't be moved without the flap lever in the up position.'

I was on my initial conversion 'sim' phase when PI was lost, but I'm sure the flap/droop interlock was in place before that accident. There had been a suggestion that some captains were in the habit of raising the flaps as soon as they were airborne, having utilised their effect of minimising the take off run, and by their retraction improving the 2nd sector climb angle.

By doing so, they were removing the lock on the droop at only two or three hundred feet.

The DC10 had a mechanical link between the trailing/leading edge levers, so that both levers moved together, and only the last selection would retract the slats. The system was (IMO) foolproof. Conversely, the Trident arrangement was an accident waiting to happen.

Hobo

16th Dec 2010, 18:04

AD, you could be right, does anybody else remember something being done to this lock after PI ...?

I think there might have been some who did what you describe.

slast

16th Dec 2010, 19:00

AD, some captains were in the habit of raising the flaps as soon as they were airborne
I have to say that I don't believe I ever encountered anyone who did this in 9 years as an F/O, in fact I can't even remember hearing about it being done. But that may just be my memory having a gap in it.... and I can't recall the sequence of design/mod to that interlock.

slast

16th Dec 2010, 19:18

Wookey, cruise at high speed... underpowered or due to lack of lift from the wing design.... lower drag and higher cruise speed.
Interesting question and I have no idea what the answer is! Certainly we flew initially at M 0.88 but it wasn't long before .84 became the norm. I think one of the factors was fuel burn and another was tendency to catch up with other traffic in airspace that was still largely procedurally controlled (not much secondary radar in those days).

Aileron Drag

16th Dec 2010, 20:03

I hope this link works. it is to the AAIB report into PI. Have a look at page 39 - the Fox Hotel incident.

Air Accidents Investigation: 4/1973 G-ARPI (http://www.aaib.gov.uk/publications/formal_reports/4_1973__g_arpi.cfm)

blind pew

16th Dec 2010, 20:04

SLAST
I spent three days researching the testimonies in the BA museum and made a FOI request to the AAIB.

I have written a biography but due to advice from counsel have put publishing it on hold.

Cunningham's testimony I have read in full and there is a reference to him in the accident report.

As has been pointed out we flew a different noise abatement procedure than that recommended by Davies who was the ARB test pilot , it is in handling the big jets.

There is also a file on his testimony which I do believe is not mentioned in the official report. I missed reading this which I regret and at the time I didn't understand the significance that he isn't mentioned in the report.

The report states that there was a baulk (or interlock) fitted between the levers as there was a theory put forward that if the down selection wasn't made correctly then the droop could automatically move when the flap lever is selected up .

I remember playing with the levers with the engines off and realised it was balderdash - the theory is in the report.

There are several opt out clauses on FOI which the AAIB used after they had retrieved the files for me.

Two important questions they couldn't answer under these constraints, one was whether my letter about our training had been submitted by FM to the inquiry.

But I had a very interesting conversation from one of the accident inspectors.

The main points of this conversation for this forum were his distancing himself and the AAIB from the inquiry conclusions and that the simulator flying characteristics were markedly different those of the aircraft.

The other interesting testimonies were George Childs who had quizzed me on what to do with a stall warning and had tried to get management to introduce a correct stall recovery procedure, Evans, Holloway and one training captain who said he had interviewed numerous co pilots who, to a man, had recounted a stall recovery procedure which was rather different to that which I had been taught and was in my flying procedures - those of us on the fleet at the time will know what I am getting at.

Hobo

Sorry I will not go into much detail on the forum but somewhere in the inquiry report it says words to the effect that co pilots were provided to ASSIST the Captain as the Trident was to complicated to be operated by one pilot.

Contrary to what was stated in equally sharing the flying, I achieved around one leg in five and when I was initially P2 only I flew EIGHTEEN sectors RHS without being allowed to attempt a landing.

And if you really want to look at the BEA field of influence - I joined the week the Vanguard dug a hole near Ghent - this was followed by another six or seven aircraft in my 6 years in BEA.

All bar one were 100% our fault - except for Zagreb although the report stated that if the crew had looked out then the accident might have been avoided.

Other prangs were the viscount flew into cloud wiv hard centre.

Cyprus T2 - low slow during training - became XM.
Two 707s .
Bilbao 1E.

I left BEA in 1978, the accidents didn't initially - so it wasn't my fault your honour.

BOAC didn't destroy anything during this period.

I owe a huge amount to some of the ex national service pilots and Hamsters on the Trident and without their nurturing I would have never successfully completed my transition on the Iron Duck.

blind pew

16th Dec 2010, 20:20

Flap retraction after take off - yes I witnessed that as well.

Even got to Burnham off 27 left at 365 knots and three grand.

Re high speed cruise / wing performance.

The Trident one approached around 30 knots faster than the DC 8 - I know as had to go around on my annual route check when an Eitie didn't understand " keep 180 knots to the outer marker" and reduced to an approach speed 30 knots below our minimum.

I believe that we rotated at a comparatively high speed due a very dirty wing and lots of drag. Don't forget that the T1 had a rather crude droop compared to the T2.

The clean wing was very thin - I believe that MMO was .92 but later reduced to .885 - therefore power wasn't a problem in level flight.

We used to race the Swiss Coronados (which were equally hot) into LHR - best trick was to get underneath them and match their speed.

Happy days.:O

Trident Sim

16th Dec 2010, 20:28

Aileron Drag

The DC10 had a mechanical link between the trailing/leading edge levers, so that both levers moved together, and only the last selection would retract the slats. The system was (IMO) foolproof.

Not wanting to go too far off topic, but the DC10 system, whilst better, was not foolproof, as a couple of stalling incidents in the mid 90s showed. One of these was on approach, when flap was selected out, but not the slats. It needed a bit of wear and tear on the levers and linkage, but it could, and did, happen.

Hard to believe, I know, especially if you know the linkage between the two levers, but I was on the fleet at the time, and watched in amazement as a TCP showed me exactly how the two levers had been (inadvertently) separated on one of the incident flights. Like watching a conjuring trick, you know what you've seen, but you don't believe it!

I believe Boeing got it right, with the single lever concept.

Regards

Trident Sim

DozyWannabe

16th Dec 2010, 20:40

There had been a suggestion that some captains were in the habit of raising the flaps as soon as they were airborne, having utilised their effect of minimising the take off run, and by their retraction improving the 2nd sector climb angle.

Interesting - I seem to recall though that Captain Key (the PIC on PI) was in fact very much a stickler for by-the-book flying, his one concession being a tendency to engage autopilot early in the climb.

I believe Boeing got it right, with the single lever concept.

Some 727 pilots worked their way round that by popping CBs though, so no system is completely foolproof.

ChristiaanJ

16th Dec 2010, 21:23

Following this with great interest, even though the "Gripper" was 'before my time'.
Some 727 pilots worked their way round that by popping CBs though, so no system is completely foolproof.This of course calls for that classic remark:
"It's so difficult to make anything fool proof, because fools are so damn ingenious..."

CJ

DozyWannabe

16th Dec 2010, 22:00

Following this with great interest, even though the "Gripper" was 'before my time'.

I have a very strong belief that the avionics of your beloved bird owed a great deal to the advances made on the Trident - I understand that Lockheed later poached a lot of the avionics guys to work on the Tristar too.

ChristiaanJ

16th Dec 2010, 23:30

I have a very strong belief that the avionics of your beloved bird owed a great deal to the advances made on the TridentI don't think so....
I'd be the last one to restart the "Smiths/Elliotts war" of the time on a forum and a topic like this, a subject so much better discussed today over a pint at the local!

But it's a subject worth discussing, and I'll be only too pleased to see other input!

For me, there are two key differences between Trident and Concorde.

The first one is, that Smiths went for the "triplex" solution, with three computers continously "talking to each other", and checking that all three were "reading from the same song sheet".
If they didn't agree, no autoland.

Elliott, who did the VC10, and then Concorde (with SFENA), went for the alternative "duplex monitored" solution, with two computers, where each of the two was effectively two computers in one, with a "command" and a "monitor" channel being compared continously.
If the two halves didn't agree... end of story : the computer would disconnect and hand over to the other one, which up to then would have been a "hot" standby.
Otherwise, the two computers basically did not "talk to each other".
BITE (built-in test) was used to assure that both computers were still serviceable just before committing to an autoland, thereby reducing the 'time at risk' of a common failure to a couple of minutes, and the resulting risk of such a failure to "highly improbable".

The other difference was simply a matter of age.

The Trident system came into being before the arrival of integrated circuits.
Now, I've never had a real opportunity to dive into the Trident electronics, but going by other systems from the same period, I would expect it to be full of things like magnetic amplifiers, transistor-based operational amplifiers, and transistor and relay type logic.

Concorde happened just at the time of the arrival of the first integrated operational amplifiers and the first integrated logic circuits.
At that time, integrated circuit development was going so fast, that the avionics on the prototypes, the preproduction aircraft and the production aircraft basically ended up using three succesive generations of integrated circuits..... (for the conoscienti here... think 165, 709 and LM101 for the opamps, and RTL, DTL and TTL for the logic).

So, to make sure we agree... the Trident and Concorde both, certainly profited hugely from the pioneering work of the BLEU, and the experiments with the Lear system on the Caravelle.

But, IMO, they diverged afterwards.

CJ

411A

17th Dec 2010, 01:36

I understand that Lockheed later poached a lot of the avionics guys to work on the Tristar too.
Actually, it was Collins Radio Corporation, who designed the dual/dual autoflight system, and as I recall, they came from Smiths, all four of 'em.

Dan Winterland

17th Dec 2010, 10:17

Smiths made the very first operational automatic landing system - as fitted to the RAF Victors and Vulcans. It was a different system to the civilian ones though.

Prober

17th Dec 2010, 22:52

Indeed! When fairly new on type, I was pre-warned, but even so slightly alarmed when a well known Captain from a far flung part of the Empire insisted on flap being fully retracted by 500ft. Interesting and exciting, but not now part of the aviation scene. Getting old.
Prober

Wookey

18th Dec 2010, 11:15

Maybe dumb question but was the Trident the first aircraft to have wing leading edge lift devices (slats or droops or whatewver you call them)?
Dont recall noticing them on other aircraft of the era or earlier that I flew on like Caravelle, comet etc.

ChristiaanJ

18th Dec 2010, 13:30

Maybe dumb question but was the Trident the first aircraft to have wing leading edge lift devices (slats or droops or whatever you call them)?
Dont recall noticing them on other aircraft of the era or earlier that I flew on like Caravelle, comet etc.If you mean airliners, I don't have a quick anwer.
But wing leading edge devices as such go back to WWII, and probably even pre-war. Some Messerschmitts come to mind, and the Fieseler Storch STOL, but the list is much longer.

CJ

petermcleland

18th Dec 2010, 14:56

If you mean airliners, I don't have a quick anwer.
But wing leading edge devices as such go back to WWII, and probably even pre-war. Some Messerschmitts come to mind, and the Fieseler Storch STOL, but the list is much longer.

...and includes the Tiger Moth :)

rogerg

18th Dec 2010, 15:10

gonebutnotforgotten

18th Dec 2010, 18:38

Re earlier question on what changes were made to the flap and slat/'droop' system post PI, the story isn't quite right. There always was a flap/droop balk so that if the flaps were not up, the droop lever could not be moved inadvertently or otherwise. What killed PI was that having moved the flaps up, there was nothing to stop anyone raising the droop at a ludicrously low speed. The claim that a single lever would have prevented PI is questionable - it is just as easy to retract slats early with one lever as two, you just have to forget what you are doing, as someone just proved recently with an A320. The Stan Key Memorial Mod was to add a speed balk to the slat/droop lever, set, if I recall, at a nominal 208 kt.

An even earlier post asked how it flew, thinking it might be difficult. Actually as Pete Mcclelland and others have said it was a doddle once a whole lot of cr*p acquired in early training was ignored and people went back to treating it like an aircraft. No thrust/pitch couple, little asymmetric yaw, super crisp ailerons, immaculate High Mach behaviour, and a 'classic' trim system that left you knowing exactly where you were. The only inconvenience was the position of the thrust levers (sorry, throttles) which were indeed a bit of a stretch, but that didn't stop the final iteration of Trident handling being just like any other aircraft, with the handling pilot handling (gasp!) his own throttles.

Finally despite rumours to the contrary the aircraft was not speed unstable on the approach, Vat was above min drag at the appropriate flap setting, and experienced hands could carry out an ILS hardly moving a muscle. Nothing since has come close (though I only encountered the splendid L1011 in the sim so perhaps there is room for argument, 411A).

ChristiaanJ

18th Dec 2010, 21:04

[Tiny O/T...]
Vat? Wot's dat?
Two seconds on Google.
It's Velocity At Threshold, and merely a term I personally wasn't familiar with.
Never too old to learn....
[End O/T]

CJ

411A

19th Dec 2010, 00:27

Nothing since has come close (though I only encountered the splendid L1011 in the sim so perhaps there is room for argument, 411A).
L1011, very speed stable...pitch too, thanks to DLC.
A pilots dream...with dual/dual (not triplex) autoland thrown in.

Wookey

22nd Dec 2010, 09:41

Reluctant to let this thread die as I have enjoyed reading the insights into this interesting aircraft (as have others judging by the number of posts) so here goes with another (naive) query.

The Trident had leading edge slats whereas I believe that the 1-11 had a fixed leading edge. Was the 1-11 wing design that much more efficient than Trident or was it simply a power:weight factor?

Swedish Steve

22nd Dec 2010, 15:23

The Trident had leading edge slats

The original Trident 1C had leading edge droop. It wasn't a slat because there was no slot, otherwise worked the same.
But for us engineers, very difficult to make it work properly. Rigging it after a component change took 8 hours.

Wookey

23rd Dec 2010, 08:24

The original Trident 1C had leading edge droop. It wasn't a slat because there was no slot, otherwise worked the same.

Sorry, SLF ignorance. Hadnt appreciated the distinction between droops and slats !!

Original question remains though. Does anyone know why Trident had the extra lift devices over the 1-11?

Hobo

23rd Dec 2010, 10:30

Pedant mode on.....

It's flaps, slats but droop, not droops.

....pedant mode off.

Wookey

23rd Dec 2010, 11:42

Hobo

It's flaps, slats but droop, not droops.

hahaha. Ok if we are being pedantic, and to satisfy my curiosity, if there is one 'droop' on each wing, should the plural not be employed? Or do you consider the aircraft to have just one wing rather than a port and starboard? Or is there something else? :confused:

gonebutnotforgotten

23rd Dec 2010, 11:56

A definitive answer requires input from someone in the project office at the time, but a few pointers are clear: the Trident was designed to be as fast as was feasible in the early 60s. This meant a good high speed wing section, and with the wing sections available at the time, a relatively high sweep back (I don't recall the exact number but a comparison with the 1-11 shows that the Trident had a lot more). Such sections are also not noted for good high lift at low speeds so a degree of 'variable geometry', in this case camber, was needed to keep take-off and landing speeds, as well of course field lengths, within bounds. As it was the aircraft had the reputation of a ground gripper (though that has a lot to do with the installed thrust). Its contemporary the 727 sprouted even more impressive high lift devices as Boeing wanted even better field performance though I think they weren't aiming at quite such high cruise Mach (T1 MMO - M0.88, 727 0.84 at a guess). Nowadays advanced sections allow the same Mach cruise with about 15 degrees less sweep and better low speed performance, but once the moving leading edge genie was out of the bottle it was employed to optimise the designs and all the current crop of airliners use them.

Wookey

23rd Dec 2010, 12:03

Gonebutnotforgotten

Thanks for that explanation, makes perfect sense to this humble SLF. However as you say it would be interesting to hear from anyone who might have been involved in the design or planning process.

Hobo

23rd Dec 2010, 12:14

Wookey AFAIAA it has never been referred to in the plural apart from the non pilot origin PI stuff and here. Flaps and slats are referred to in the plural because there are usually more than one section of each on each wing, but there was only one section of droop. On most types, the call is Flap 1,5,30 etc. I.e. in the singular.

Based on my experience of over 6000 sectors and around 10,000 hours flying Tridents of all types plus over 100 simulator sessions and being involved on the technical side as well; I'm here to tell you, it's droop not droops.

Wookey

23rd Dec 2010, 13:02

Hobo

Fair enough. Having re-read my earlier reply I can see that it might be misconstrued. However it was a genuine question as to why droop would be singular but flaps and slats were referred to in the plural which you have now explained perfectly. Apologies if you thought my response impertinent.

Merry christmas to you and all contributors to this thread

bizdev

23rd Dec 2010, 13:28

Not sure whether I dreamt it, but I seem to recall that the original DH Trident design was of Trident Three size with Medway (larger) engines and slats (not droop) leading edge devices - then BEA got involved by demanding a smaller and "simpler" aircraft - hence the T1 with Speys and droop L/E?

stilton

25th Dec 2010, 05:09

Gone but not forgotten.

MMO on the 727 was .92 Mach, actually making it a little faster.

it was very comfortable at that speed, although a little noisy, like the Trident it was a superb high speed aircraft but with its elaborate wing still able to have good field performance.

777fly

25th Dec 2010, 15:19

The T1C wing was certainly optimised for high speed cruise, as it had 38 degrees of sweepback, and high lift devices were required to get acceptable lift off the wing for takeoff and landing. It had a Vmo of 380 kts and, if I remember correctly, a Mmo of 0.93M and cruise of .885. this was later reduced to 365kts and 0.85M cruise to come into line with the T2, which at 35 degrees sweepback was a little slower. The B727 had a higher Vmo but surely not a higher Mmo, as we used to leave them standing in the cruise.

The T1 had excellent high speed handling. I remember seeing over 0.95M during our high fly exercise (cb pulled) and there was no buffet or airflow separation, even turning at 30 degreees of bank, just a slight rumble from the ailerons. During the emergency descent manouevre, the rate of descent could only be determined by use of a stopwatch and the altimeter between FL300 and FL200, as the VSI was jammed onto the bottom stop. It was in excess of 18,000 fpm, a capability the ATC soon learned to make good use of.

In the late 60's as the autoland system was developed and proved, we were initially only allowed to carry out 'autoflare' landings, with roll control provided by the pilot. After a certain number of these had been completed we moved onto full autoland, right down to Cat 3c capability. This was found to be impracticable, as in complete zero vis it was impossible to taxy or be found by the emergency services, so Cat 3b with 75 metres vis was established as the working minimum.

A further feature of the T2 was water injection for the Spey 512 engines. This was used to uprate the performance out of short and/ or hot airfields, such as the old Malta Luqa or Nicosia airfields. This provided about three minutes of sporty performance, but the water usually ran out at about 20 kts below the slat retract speed, leaving the aircraft ' hanging' in ISA +15 air and very reluctant to accelerate. A very long practically level segment was required to get up to clean climb speed. The system was not used extensively and was soon withdrawn, as a water injection pump failure left a tank of water on board which could freeze at altitude.

While I can still remember:
T1 full tanks: 13680 kgs
T2 full tanks including fin fuel 23040kgs
T2 full tanks without fin fuel 21809 kgs.