727 Early high sink rate crashes [Archive]

misd-agin

10th Jul 2008, 16:58

barit1 (http://www.pprune.org/forums/members/107138-barit1)

Join Date: Feb 2005
Location: flyover country USA
Age: 66
Posts: 2,142

There were four within six months. All had high sink rate, unarrested descent.

UA Lake Michigan 8/65 (http://www.ntsb.gov/ntsb/brief.asp?ev_id=74466&key=0)

AA CVG 11/65 (http://www.ntsb.gov/ntsb/brief.asp?ev_id=72940&key=0)

UA SLC 11/65 (http://www.ntsb.gov/ntsb/brief.asp?ev_id=72941&key=0)

All Nippon - Tokyo Bay 2/66 (http://aviation-safety.net/database/record.php?id=19660204-0)

Additionally a PA ship crashed 11/66 (http://www.ntsb.gov/ntsb/brief.asp?ev_id=22245&key=0) in E. Germany, suspected similar circumstances
Last edited by barit1 : 7th July 2008 at 21:50.
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The UAL crash into Lake Michigan was miles (20+?) from the airport. Indication of misread altimeter, by 10,000, caused the accident. During descent accepted a descent to 6,000. Unfortunately a/c was already at 2,000, well below it's cleared altitude.

AA CVG was visual approach and they lost sight of the airport. Crashed 4 miles from the runway and is more consistent with CFIT as opposed to unstabilized final approach segment.

All Nippon Tokyo impacted 12 kms from the airport. CFIT as opposed to unstabilized final approach segment.

Pan Am East Germany crash - crashed over military training area on initial approach segment. Some suspected accidental shoot down by East Germany/Russian military. Western crash investigators weren't allowed on site. Eventually some of the parts were unexpectedly driven to the West Berlin border and handed over. (Pan Am brat in West Berlin at the time). Final cause was unknown, but it wasn't unstabilized final approach segment crash.

grumpyoldgeek - in my opinion (IMO), except for the UA SLC crash, these accidents don't qualify.

You can search www.airdisaster.com (http://www.airdisaster.com), or other crash investigative websites, and enter B-727 in the databases. There might be others that IMO would qualify. I'd also check out B-707, DC-8, DC-9 and B-737 crashes in the 1960-1970's. They might have had some unstabilized final approach segment crashes that are, over time, getting lumped together.

misd-agin

10th Jul 2008, 17:13

Barit1,

Just reread my post. We could get into a circular argument about high sink rate, unarrested descent vs. CFIT crashes. Almost every accident is by definition "unarrested descent".

IMO the AA CVG crash is an example. Crew took a visual approach, ceiling reported at 1500 BKN. While trying to tune ILS frequency and get established on ILS they flew into the ground. Unstable approach? Blame it on high sink rate/unarrested descent? Or perhaps basic loss of situation awareness and basic instrument crosschecking?

Me? I'd blame it on loss of SA and basic flying. The NTSB makes no mention of high sink rate/spool issues.

NTSB? PROBABLE CAUSE(S)
PILOT-PLTS DID NOT MONITOR ALTIMETERS DURNG APPRCH
WEATHER - RAIN

misd-agin

10th Jul 2008, 17:18

grumpyoldgeek,

After rereading you post I realized I focused on the high sink rate and unspooled portion of your post. Had I focused on the "not flying the approach by the numbers" I would agree that all of these crashes can be attributed to that probable cause.

That's almost a Catch-22 - did poor flying cause the crash? Yes. IMO only one is directly attributed to high sink rate problems(SLC), AA CVG might have been except they crashed 4 miles from the airport as opposed to less than 1-2 miles from the field.

PantLoad

10th Jul 2008, 18:53

It's been almost 25 years since I flew both the 727-100 and 727-200, but as I recall, the SOP for that aircraft at my company required being stabilized on the approach no later than 1500 feet AGL (as opposed to 1000 feet AGL for the other aircraft in our fleet). This was due to the aircraft's ability to develop high sink rates with a dirty configuration, relatively low airpseed, and unspolled thrust conditions.

While I haven't that much time in the 727 (maybe only 2800 hours total time), I recall that, in order to get a good landing, the flare technique was somewhat different from other aircraft I flew. As I recall, as you came across the fence, you eased back on the yoke slightly...as doing so, increasing thrust slightly. Then, as nearing the runway, we relaxed the back pressure...perhaps even pushing a bit on the yoke...and perhaps increasing just a bit more thrust. Such techinque resulted on rolling it on at Vref +5 to Vref +10 or so.

Again, as I recall, the airplane stopped well...so much so that the nose wheel brakes were removed by most carriers....not necessary. Between the big main wheels and brake assemblies, and the reverse of those three engines, stopping usually wasn't a problem.

Overall, the airplane flew like a dream. I loved it. But, you had to be careful not to scrape the tail skid...especially an issue on the -200 model. Thus, on takeoff, we normally did the 'two-step' rotation technique. I can't recall, specifically, the numbers...but I'm thinking the -200 hit the tail skid (struts compressed) at 10.5 degrees nose up...11.25 degrees nose up on the -100...so, we did the first step rotation to about 9.5 degrees, until she lifted off, then, further rotated to an initial target pitch of 15 degrees (+/- for the various factors).

Sorry if my memory is failing...which is proved daily...so, someone please correct me.

PantLoad

con-pilot

10th Jul 2008, 19:48

Sorry if my memory is failing...which is proved daily...so, someone please correct me.

No, that's pretty accurate. I ended up with about 7,000 hours in the 727, mostly in the 100. I my experience as well I found the 100 much easier to land smoothly than the 200. If fact it is astonishing how fast you can stop a 727 on landing.

Now, in regards to the flaps 40 landings. We were cautioned about the high sink rate that you get into with 40 flaps, however, we were told that reason that most airlines had blocked out the 40 position was two fold. First was for fuel savings, it takes a lot more power at flaps 40 verus 30 on final and secondly for noise abatement. We had flaps 40 available on our 100s and 200, we seldom used that position for the above reasons. When the aircraft were modified for stage III the 40 position were blocked. However, we could remove the block if we deemed it necessary for operational reasons.

One thing I can tell about landing with flaps 40, when you pull the power off, you land, right then. I never dumped the 02 masks, but I've been on board when other pilots did. In fact one memorable landing a guy not only dumped the masks, but the life rafts as well. And that was a flaps 30 landing.

wileydog3

10th Jul 2008, 20:10

I got the privilege of flying the 727-100, the -200 with the -7, -9 and -15 engines along with two re-engined 727s with the JT8D-200 series engines. It was not a difficult machine to fly but it did require planning.

The initial flaps dribbled out very slowly but it was possible to go to flaps 25 without the gear horn that could NOT be silenced. Flaps 30 or 40 and you had the horn. Drag increased considerably beyond flaps 15 but it was possible to leave thrust at around 2700-3000lbs/eng and configure to the next flap setting as the drag increased. And you could actually go down AND slow down in the 727, something not available in the 737 or the 757/767.

At flaps 30 the machine was very stable BUT if you had a speed decrease, it was necessary to keep adding power until the speed decay was arrested and then start bringing power back off. You could NOT add a bit of power.. add a bit of power and arrest the speed decay. You had to be aggressive.

Flaps 40 increased drag considerably but not unduly. I had flown the KC-135 and we used flaps 50 so maybe I was conditioned. Some fellow aviators never used 40 but if you added about 4-500lbs/hr/eng, things worked out nicely, especially on wet or contaminated runways. We used to call flaps 40 "give me 50 percent wing disassembly'. Our flaps 40 position was never locked out although I believe after the merger that did occur. (I got bumped during the merger).

You could definitely develop a high sink rate in the 'seven two' but you could also do that in the early Lear 20 series.

As for landing, there were multiple techniques. For me, it was reduce power and hold the nose exactly where it was. Others used a BIG flare and many of the BI guys had perfected the 'shove' where they released a bit of back pressure after the slight flare and that cushioned the landing.

I never got the 'rubber jungle' in a landing but had a few friends that did. You could definitely rattle some teeth with a firm landing.

The Mighty Tri-Motor is one of the grandest flying machines ever built IMHO. I enjoyed my time on it although I could never figure out the slightly off center yoke in the -100. I enjoyed the 727 much more than my time on the 737.

Fantome

10th Jul 2008, 20:43

That slight pole forward before a skating on greaser was something I saw many times watching from the holding point. Arsey and classy it looked.

Straight after the early prangs in the states a movie was made about the techniques for a safe, stabilised approach, widely distributed to 727 operators.

Rather sorry never to have made it onto the three holer. She of the ventral entry. First encounter was at Mascot in '62 when the demonstrator came in on it's world tour. Plastered with all the logo stickers of all the airlines that had ordered them. Sales staff handing out all the pins and ties and little diecasts you asked for. And just about any odd or sod could cadge a ride.

PantLoad

10th Jul 2008, 20:54

Wileydog3....

Did you fly the early KC-135 with the old engines that had water on takeoff? How much thrust did those engines have...both with and without
water?

It's my understanding that the max takeoff weight for the 135 (under war time conditions) was 300,000 lbs. Is that correct?

Just want to calculate the thrust to weight is with one engine inopt. I heard the plane, at 300,000 lbs, didn't fly too well with one engine inopt.

PantLoad

Jumbo Driver

10th Jul 2008, 21:11

There was also this (http://www.gatwickaviationsociety.org.uk/YA-FAR.asp) accident, involving B727-112C YA-FAR of Ariana Afghan Airlines on approach to runway 27 (as it was then) at London (Gatwick) on 5 January 1969.

Although never having flown the 727, I have to say that I have always understood it to be "potentially unstable in the landing configuration".

JD
:)

grumpyoldgeek

10th Jul 2008, 21:44

Thanks for all the great info. This is stuff that isn't available anywhere else in the world. Shades of Earnest Gann's writing here.

Thus, on takeoff, we normally did the 'two-step' rotation technique. I can't recall, specifically, the numbers...but I'm thinking the -200 hit the tail skid (struts compressed) at 10.5 degrees nose up...11.25 degrees nose up on the -100...so, we did the first step rotation to about 9.5 degrees, until she lifted off, then, further rotated to an initial target pitch of 15 degrees (+/- for the various factors).

I remember those two step rotations as PAX, flying out of SEA and PDX. The second rotation felt more like 45 degrees in the back.

TWApilot

10th Jul 2008, 22:01

ILG,

You stated that TWA's blocking the Flaps 40 was for an unrelated reason, but I can tell you that while in 727 class at TWA we were told specifically that the Flaps 40 setting was blocked as a direct result of the SLC accident, related to excess drag at flaps 40. Had they been at Flaps 30, the sink rate could have been arrested and there would not have been a problem.

con-pilot

10th Jul 2008, 22:29

You stated that TWA's blocking the Flaps 40 was for an unrelated reason, but I can tell you that while in 727 class at TWA we were told specifically that the Flaps 40 setting was blocked as a direct result of the SLC accident, related to excess drag at flaps 40. Had they been at Flaps 30, the sink rate could have been arrested and there would not have been a problem.

Sorry, I should have included in my post that in my training, Dalfort ie. Braniff, that we were told that some airlines did block out the 40 position for the sink rate issue as well for fuel and noise.

If I recall correctly with flaps 40 you needed around 5,000 fuel flow but only 3,000 with 30 on final. For minor power adjustments I just used #2 and left 1 and 3 at a constant setting.

One of the things I loved to do in the 727, when able, was to close the throttles at 10,000 feet and not touch them again until flaps 30 and gear down. Usually could not do that because of ATC and/or traffic.

Robert Campbell

11th Jul 2008, 02:08

The problem with the 727 that was not understood initially was the deep stall.

The T design of the horizontal stabilizer elevator allowed the wing to blank the tail when the airplane was allowed to get too slow in a nose high attitude.

The drag of 40 degrees of flap could slow a 727 pretty rapidly unless a lot of power was added at the same time as the flaps were lowered.

The airflow to the aft mounted engines was also disrupted. With the elevator or even a stabilator in this condition (nose high and slow) and no air getting to the engines, the aircraft was uncontrollable. It was stuck in a stalled or near stalled condition.

This was new territory in this second generation jet, and several were lost before the problem was figured out. Flap limits and higher minimum airspeeds took care of the problems, and as long as the new limitations were adhered to, the aircraft was safe.

As for the difference in landing performance between the -100 and the -200, it had to do with main gear position in relation to the CG. when flaring the longer -200, the main gear could be slammed into the runway as the nose came up. Hence the slight pitchdown or relaxation of back pressure on the control wheel just before touchdown that savvy pilots learned.

We don't see designers opting for T tails these days.

Centaurus

11th Jul 2008, 03:28

back on the yoke slightly...as doing so, increasing thrust slightly

I never flew the 727 but have fair amount on the various 737. Interesting about your point above of increasing the thrust slightly during the flare.

I have seen this technique used in the 737 and also in the simulator. When asked the pilots concerned their technical reason for giving a "burst" of throttle at the flare, people couldn't explain why - although I realised after watching many of these power bursts it was often a reflex action - despite their aircraft was perfectly positioned in the flare for a good landing. In other words it seemed a good idea at the time!

In the simulator I found it difficult to convince some 737 pilots that there was simply no point in this burst of thrust as all it did was cause the aircraft to sometimes balloon slightly and land deeper into the runway. In some pilots this habit was so ingrained one could not break it rather like the jerk that occurs involuntarily when you hit your knee lightly.

lederhosen

11th Jul 2008, 09:28

Although everyone knows the standard Boeing 737 technique, I am always amazed by the variation in how colleagues actually flare, and in the end result! Flying a mixture of classic and NG also encourages different techniques.

For various reasons the NG is definitely less forgiving in the flare. Recent trips with Ryanair have demonstrated this when paxing. My answer to the Centaurus question, why blip the power, is that increasing power on the 737 also raises the nose. We tried a few blocked elevator approaches a few years ago, with time left over in the sim, which was extremely enlightening.

We actually call the somewhat firm arrival a 'Boeing landing' in my company. The Boeing push as it has been referred to elsewhere and described a couple of posts above by Wiley Dog seems to work for some. At the end of the day passenger perceptions of the landing come way behind considerations of safety and convenience such as taxi distance etc.

In the sim I stick to the standard technique as frankly I am unconvinced about the fidelity of the sim in the flare and anyway there are no pax and cabin crew to worry about.

Slats One

11th Jul 2008, 10:22

Finally, thanks to Robert Campbell's post, we get to the point...

T Tail, rear biased wing, airflow over tail, high sink rate. airlfow compression and strut effects, localised drag envelope, and g break effects.

Its simple and applies to other T tailers too!

Isn't the rule on the RJ 146 (T tail but wing mounted engines) to add power and that once you start hauling on the stick she's coming down like a lift unless you whap on the the thrust?0

727 -Never get low and slow- an old rule methinks.

Get a T tailer low and slow, and all the adverse factors will combine in one almighty moment- and lead you to disaster- a massive sink rate and then, if you sit their fat and happy and have not rammed on LOTS of power in one go, they will fall over backwards in deep stall.

The high T tail gives more moment arm of authority and better airflow over the elevators authority except during take off and nose high approach- because the tail surfaces ( the horizontal ones) - 'dip' into the wing wash and become less effective. Whereas a conventional low tail dips below the wash in nose high attitude and is thus more effective.

On a certain light buisness jet, there are some lovely angled vanes under the rear end which dip below the wing wake when too nose high and pitch the tail up - as required.

The 727 - like the VC10 - has a very tall tail fin - the vertical empenage - thus delaying the 'dip' performance loss by keeping the elevators higher than they are on say - a Trident a BAC 1-11 or on one of those stubby tailed modern twinjet T tailer feeder airliners that also lack thrust reverse.

In the development years , Boeing, Douglas and Vickers all shared knowledge on the performance issues of the T tail- and the DC-9 had its tail made taller and its horizontal stabilisers made wider as a result.

The Russians knew too- show me a Russian design T tail rear engine jet with a Trident or BAC 1-11 style, short, low stubby T tail- there are none- they all follow the 727 and VC10 type high fin, broad elevator design - with or without end plates on the fin top.

It is not true that desingers are eschewing the T tail these days- as claimed in these posts. Embraer, Bombardier, Lear, Gulfstream - etc all still deploy the efficiency of the T tail- which by the way was invented by a certain Hans Multhopp in 1930s Germany - he worked with Kurt tank and in June 1945 under 'Operation paperclip' was grabbed and sent to the RAE at Farnborough (along with the Horten brothers) until the Americnas grabbed him and gve him a new life in the USA where he made major contributions to US aviation design and lifting body design.

So, the 727 early handling issues were down to power, flaps, attitude and an understandable failure by pilots and the community in general to really appreciate that when the book says add power on approach and make sure you have deployed the lift protective slats, it meant do it and do it big time- not in a drip drip application.

The 727 wing was amazing - what a plane - handled like a dream. Just avoid being wing clean at 180 knots with low power and no anticipation dialled in to the brain. Just like on then VC10 then - or so say those far better experienced than me.

lederhosen

11th Jul 2008, 11:13

Anyone remember the classic flight test picture of the 727 demonstrating a go-around, I think at Renton circa 1963? The nose is pitched up at what appears to be an impossible, well extremely impressive, angle towards the sky. The gear is up and the ground extremely close. It gives pause for thought, given some of the comments on here about flying the aircraft.

Tyres O'Flaherty

11th Jul 2008, 11:29

Makes me wonder.

I'm sure many of you have seen that film of ( I beleive it was NASA ) 727 test landing, where the tail + last few meters of empennage is ripped off, due to excessively high sink.

The test being conducted was a high sink landing thing, except that the pilot exceeded parameters.

I am wondering whether the test was done because of the specific problem with the 727 discussed here ?

( i.e. research into the causes...)

WHBM

11th Jul 2008, 11:48

We don't see designers opting for T tails these days.
I think that with the numbers of Bombardier and Embraer RJs built in recent years (over 1,000 of each), plus the previous generations still in service, there are probably more T-tails in service now than at any time in previous decades.

Those early 727s would have been handled by high time DC6 etc crews, maybe even dating back to WW2 experience. The RJs nowadays are often crewed by those on their first airline position. Yet those early 727 difficulties are not encountered. Reason ?

An analysis I saw many years ago about the early 727 accidents and the subsequent investigation stated that even the test pilots found they were getting caught out in certain circumstances, apart from one guy who was ex-Navy with carrier landing experience. I wonder what that experience was that aided him ?

We actually call the somewhat firm arrival a 'Boeing landing' in my companyWhen I first met Russians they talked about how Russian crews made such good landings compared to BA on the A320, which I regarded as so much nonsense. After quite a lot of exposure to Tu154s since then I can tell you that every single landing has been a greaser, it really is quite amazing the difference in landing capability. I wonder if anyone can attempt a justification.

I'm sure many of you have seen that film of ( I beleive it was NASA ) 727 test landing, where the tail + last few meters of empennage is ripped off, due to excessively high sink.I believe the film you are referring to was actually the MD-80 prototype in October 1979 at Edwards AFB, which had an FAA crew handling it at the time and which did indeed exceed the design sink rate (not that it looked like that in the film, I have to say). McDD repaired it and attempted to deliver it to customer Swissair, who refused to have it. Nor would anyone else, after about 10 years it was broken up.

Brian Abraham

11th Jul 2008, 11:49

Twas a DC-9 Tyres. Couldn't find the video on the web I'm afraid.

Tyres O'Flaherty

11th Jul 2008, 13:06

Aha that was it

Yes thank you both

Slats One

11th Jul 2008, 13:25

WHBM makes a very good point- those early crews were by historical fact, all ex prop men. They were used to nose down approaches, prop wash over the wings providing lift at low power settting, and had never encountered a 727 wing -the one that unpacks itself so that its slats and flaps hang off it like clothes on a washing line. And they and the rest of the pilot community had very little knowledge of the T tail and rear cg, rear engined handling characteristics.

the ex navy carrier pilot would of course have ben traiend in long jet powered, full flap nose high approaches onto carrier decks - that's why he was ahead of his prop history companions. Phantoms perhaps? Or soemthign earlier maybe.

Glider pilots have an analagy with the T tail low and slow- not -rule - never let the speed drop off on finals, never turn late and slow with a low airspeed - uses attitude and speed brakes as a throttle. add speed on finals -especially in a strong ehad wind- kep the wing loaded with lift and energy.

Iceman49

11th Jul 2008, 13:50

Used to fly with a captain at the National, all approaches were flown at vref+15...than he would put on wind additives, when I asked him about it, he said there were a lot of early 72 crashes from high sink rates (I think it was the unspooled engines). Made for exciting approaches at the old SRQ and FMY airports.

WHBM

11th Jul 2008, 14:02

I've just looked at the dates/times of the five accidents referred to at the start, and all five appear to have happened during darkness, something we have not touched on previously.

Also, look at that high time but very low jet experience of the skippers.

UA Chicago : 17,142 hours, 82 hours on type.
AA Cincinnati : 16,387 hours, 225 hours on type.
UA Salt Lake : 17,743 hours, 334 hours on type.
PA Berlin : 14,212 hours, 59 hours on type.

lederhosen

11th Jul 2008, 14:49

That is a very insightful analysis. I remember an amazing article in Flying magazine by Len Morgan describing his 720 transition, which was basically self taught. As he put it he had never reached cruising altitude in the airplane, before he first flew with passengers. Nothing unusual there I hear you say. But remember there was no sim and the training was done in the airplane. He was then assigned the least popular base being the old Denver airport (short runway) in the middle of winter! No namby pamby line training. Having survived that he felt pretty qualified.

Robert Campbell

11th Jul 2008, 15:46

If I remember correctly, the UAL SLC 727 accident involved the pilots getting into the nose high, high sink attitude at a rather high altitude.

The deep stall and blanked T tail and engine inlets were just starting to be discussed at the time. I do know that ADs were flying out of OAK city, and there was talk of grounding the 727 fleet. I don't remember if they were grounded, but at least 10kts were added to all minimum airspeeds.

I was flying night freight from SFO and LAX to SLC and PHX in DC-3s at the time. We used to eat at a coffee shop that was very close to the approach end of 25R at LAX. We'd watch the freighters landing while having breakfast at 2AM.

On two occasions I remember seeing UAL 727-100s just about fall out of the sky during the last 100 ft. or so of the descent, the engines finally spooling up enough to save the landings.

I have a friend who flew with me at the Otis Spunkmeyer DC-3 operation. He retired from PSA with seniority #1 just before US Air took them over. His favorite airplane was the 727-100 which he got into from the Electra. He's over 80 now. I'll call him and find out what he remembers.

misd-agin

11th Jul 2008, 16:01

3500 hrs (+/-) 727. Land the plane like any other airplane, no push over, no power in flare, etc, etc. Flare, power at idle at touchdown.

So if the a/c is speed stable, what happens in ground effect if you increase your power? :sad: Used to love watching the 130 kts approaches become the 140kt + landings, past the touchdown zone. := Ah, but it was a greaser, and the passengers loved it. :yuk:

727 had an interesting takeoff rotation. The pitch feel would undergo a slight change, almost like a slight dead spot, during the rotation. You'd rotation, the plane would assume a takeoff attitude, and then sit there for a heartbeat or two before continuing it's takeoff/rotation. I think that's where guys got the saying 'you fly this airplane off the ground'.

Slats One

11th Jul 2008, 16:45

Just checked out Morgan's "Landing the three holer" article in Flying Magazine

Morgan says that with the -200 if it started balloning on touchdown the trick was to ADD power to restore elevator authority and re-land the aircraft. If you cut the power as per so-called 'normal', you lost elevator authority and the thing would start bitching on you - so to speak..

Let's not get into the rut that the 727 was in any way dangerous- it was not - not with over 2,00 sold - and indeed as per by earlier post- like the VC10, due to its very high tail, it could climb at very steep angles -ones that would have condemned a Trident or BAC 1-11 to deep stall regime.

I once went on a LH 727 jumpseat ride out of Frankfurt in the 1980s. 3 crew of course- engineer to help monitor attitude and speed. LH rammed on the power and got the nose well up- all with no drama. On approach they poured on the power -got the Pratt's really pumping. SAS and KLm did the same thing with the DC-9 and then MD 80s (SAS).

Must have cost everyone a fortune in fuel.

lederhosen

11th Jul 2008, 16:58

I love that line, 'land the plane like any other airplane'. It all seems so easy doesn't it. I seem to remember a well known (and highly respected) parcel carrier wrote a 727 off not so long ago in Florida, during a night landing. The same carrier also operates a large fleet of MD11s a number of which have been written off during landing incidents commanded by highly experienced 727 pilots. You can fill in the caption below the picture of the smoking wreck as you wish, my preference is for 'Shoot bubba, if landing this baby is so easy, what are we doing upside down?!'

hetfield

11th Jul 2008, 17:32

Land the plane like any other airplane
Hhhm, vergiss es. (Forget about it).

Having flown that ship for 8 years, but yes A340, A320 and A300 are about (!) to land very likely. The 727-200/230 isn't.

Again, as I recall, the airplane stopped well...so much so that the nose wheel brakes were removed by most carriers....not necessaryIMHO, most airlines didn't order them at all. E.G. LH had only four out of 35 or so equipped with NLG Brakes. To my knowledge, they never ever had been used......

lederhosen

11th Jul 2008, 17:53

Good one Hetfeld, I failed to notice it was April first. Mind you, you are up way past bedtime unless you are out of time zone. Crate of VB mate?

hetfield

11th Jul 2008, 17:56

Utc +2

;)

lederhosen

11th Jul 2008, 17:58

So pretty close to God's country. Good on ya mate!

misd-agin

11th Jul 2008, 22:42

Slats One (http://www.pprune.org/forums/members/136781-slats-one)

Join Date: Mar 2006
Location: wiltshire uk
Age: 46
Posts: 37

Len Morgan's advice
Just checked out Morgan's "Landing the three holer" article in Flying Magazine

Morgan says that with the -200 if it started balloning on touchdown the trick was to ADD power to restore elevator authority and re-land the aircraft. If you cut the power as per so-called 'normal', you lost elevator authority and the thing would start bitching on you - so to speak..

Guys come up with this stuff and it becomes gospel?

Eg, the plane ballons at roughly 120-130 kts(typical landing speeds). But it needs power to restore elevator authority? How did Boeing ever get the plane certified if it lost elevator authority, especially during landing phase?
How did they ever do stalls? Approach to stalls? Slow flight? Stickshaker certification? How did guys ever fly the nosewheel onto the ground, down to speeds as low as 60, 80, or 100kts, if pitch authority was lost during low power operations.

Would guys add power in balloons? It wasn't uncommon to do so, but it's all a factor of how fast you were, how high the balloon was, etc, etc. Adding power had the benefit of an upward thrust vector, which could reduce the potential 'crunch' that might occur if the situation was poorly handled.

The plane had a fair amount of drag. Much more than current generation a/c and would deaccelerate fairly quickly with power off. IMO that's why guys felt more comfortable landing it 'hot' or with power.

It was very unforgiving of any crab on touchdown. Any crab at touchdown, and sideways drift, could make a nice touchdown seem much worse than it actually was.

Today's a/c DC-9, S80, 737/747/757/767/777, A300 are less demanding, but many folks think the 727 was the nicest flying airliner ever built.

Robert Campbell

12th Jul 2008, 00:21

Yes, the 727 did not like any crab on a crosswind landing. Being an old taildragger (conventional gear, not tail strikes) pilot from day one, it was very comfortable to watch an approach and landing with the wing down/top rudder technique.

I never flew one, but I rode jump a few times.

No engines below the wings made it possible to land with a significant bank unlike the 73s, 4s, 5s, 6s, 7, and ABs. Actually, a one (two) wheel landing in gusting conditions was a lot of fun.

lederhosen

12th Jul 2008, 05:55

I remember sitting down the back on a gusty 727 crosswind landing in Brisbane and experiencing exactly what happens when you get it wrong. It was back in the good old days and after what felt like the third bounce, as we taxied rather carefully back to the terminal, the Captain came on the PA and said, I quote: 'Sorry about that ladies and gentlemen, that was the co-pilot, we have to teach them some time.'

I think we can all agree that even if not gospel, Les Morgan was one of the greatest ever aviation writers.

hetfield

12th Jul 2008, 08:11

but many folks think the 727 was the nicest flying airliner ever built.

Yes, it's (was) a pilot's plane.

The late XV105

12th Jul 2008, 10:28

Twas a DC-9 Tyres. Couldn't find the video on the web I'm afraid.

That'll be because to be pedantic it was an MD80 as correctly mentioned by WHBM

Going to Youtube and searching for MD80 landing returned the video in question:
YouTube - MD80 Landing Crash (http://www.youtube.com/watch?v=9dSiqP78fXU)

Not surprised nobody wanted the repaired hull!

XV105

Captain104

12th Jul 2008, 12:03

@Hetfield
IMHO, most airlines didn't order them at all. E.G. LH had only four out of 35 or so equipped with NLG Brakes. To my knowledge, they never ever had been used......

Sorry. Different opinion: During 1983 and 1990, the LH fleet of B-727(FRA NG + Condor) operated with nice working nose wheel brakes. Acc. LH Flight Crew Training manual 727(dated 20th Jan 1988). Limits: speed greater than 15 kts, turned out of center not more than 5,5° and Antiskid on.

Otherwise fully agree: a pilots dream. You could sink like hell with increasing speed, or sink and slow down at the same time. Use of gear as speed brake could do wonder.
No 1 and 3 idle, No 2 about 55% N1 with small corrections and your 727 followed you in an approach down to final config. like a well educated Lady.

To watch: as mentioned before, a pretty long distance between CG and MLG. TO rotation with a short "delay" at 9,5°. No Flaps 40 in turbulence or strong crosswinds.
During flare, a slight dip left or right with a titty of power did the grease for me. Others did a grease job by "releasing" the stick a bit forward.

The are 2 AC's I dream of ( out of 12 types mil+civ) and wake up in the morning with a happy smile on my face. No 1 Boing 727, No 2 T-38 Talon.

Regards

hetfield

12th Jul 2008, 12:14

Limits: speed greater than 15 kts, turned out of center more than 5,5° and Antiskid on.

@Captain104

To activate the NLG brakes you had to press the pedal to the metal. Me thinks those planes had been sold after many years still with the origin NLG brakes. Never ever felt any temperature rise on the iron even after heavy braking.

kind regards

RWEDAREYET

12th Jul 2008, 12:16

I think the primary reason for flaps 30 landings was fuel consumption. Less noise and less chance of excessive sink rate was just an added benefit. Many operators are asking the pilots to use flaps three on the Airbus 320 family for landing these days. This is for one reason only and this is fuel conservation. If I remember correctly, was a long time ago, I think gas prices spiked in the 70's much like they are now 30+ years later. This may have been one of the primary factors.Granted the CRJ's and the ERJ's have T-tails, but that is the only similiarity to the old Boeing. The wings are completely different. The sweep on a 727 is much like a fighter jet and the sweep on a RJ is more like a prop aircraft. The wing is why a high sink rate could sneak up on you. Hence the terms energy management, spooled and stable came about. I miss the old girl, still my favorite to fly.

wileydog3

12th Jul 2008, 12:34

Did you fly the early KC-135 with the old engines that had water on takeoff? How much thrust did those engines have...both with and without
water?

Yes. I got on the 'water wagon' in 1970 after returning from Vietnam flying 0-2s as a FAC. ??? The J-57 put out an astonishing 12845lbs thrust dry and using the 5600lbs of water (in 2 minutes) pushed it up another 100lbs. That is the Dash 1 numbers and it never made any sense because the difference between a 'dry' and 'wet' takeoff was very noticeable. And even more noticeable if you lost water on a pair of engines.

When I got on tankers, it had just changed from LEFT/RIGHT water injection to INB/OUTB. Needless to say, one has to wonder how long that problem existed before someone figured out the solution to some real asymetric thrust problems. And the only powered control surface on the Boeing 717 (real one) was the powered rudder.

It's my understanding that the max takeoff weight for the 135 (under war time conditions) was 300,000 lbs. Is that correct?

Max taxi was 301,500 with max takeoff at 297,000. Out of Thailand for the fighter refuelings our usual configuration was '165 wet'. (110k empty gross, 5600lbs water, 165,000 fuel for a takeoff weight of around 280. With little more than 50,000lbs of thrust, you can see the takeoffs were always somewhat exciting. At 280k, the Vr would be around 180kts.

Just want to calculate the thrust to weight is with one engine inopt. I heard the plane, at 300,000 lbs, didn't fly too well with one engine inopt.

We had an 'S1' instead of a V1 but it was essentially the same. Never lost one below S1 but did lose one after S1 and it was just another Boeing. And like other Boeings, the magic number was 210kts. Get 210kts and clean, you are home free.

I had the privilege of going to the Instructor school at Castle in Merced. We really got to play with the machine doing lazy 8s (as much as one can in a KC-135) with a B-52 on the boom; 3, 2 and single engine approaches with missed approach (yes, below 170,000lbs you could fly a single engine approach but the go-around was very interesting and you used a fair amount of the 200ft from the CatI mins).

When I was assigned the tanker, I was quite upset. I had done a tour and had been promised fighters. I figured any machine with more than one engine and more than one engine had a basic design flaw. My ops officer, a grand fellow, pulled me aside and told me the tanker was a great design and to prove his point he asked me to go find another airplane that would lift approx twice its empty gross weight, would do 0.90M all day, had a ceiling (which I took it to) of 42,000ft (oxygen mask limit.. not airplane), had legs to cruise to Europe or throughout the Pacific and where you could still smoke and have a good cup of coffee (pre-Starbucks and before no-smoking regs).

I still check tail numbers when I see a re-engined tanker. Hard to believe something I flew almost 40yrs ago is still doing the job.

now back to our regularly scheduled thread..

PantLoad

12th Jul 2008, 12:42

As always, wileydog3, your posts are quite interesting. Thank you for the answer to my questions.

PantLoad

org

12th Jul 2008, 16:06

I guess I'm pretty lucky to be flying the 727 (again) and in a place we can really take advantage of the airplane's ability to maneuver and descend.

We quite often approach from directly over the airport at 7000 to 10000 feet and spiral down staying within about 3 miles from the threshold. At anything less than 8000 ft it can be done in one turn no problem with idle thrust, flaps 25 and gear up until on the base turn. Carry a little extra speed so the sink doesn't develop, then spool it up and curve to the final. Obviously not a pax operation.;)

The lack of pitch and yaw response to power changes makes it a dream to fly compared to aircraft with underwing mounted engines, and except for the landings, it's almost possible to "think" it around. A great combination of maneuverability and stability.

misd-agin

12th Jul 2008, 17:49

Captain 104 - "The are 2 AC's I dream of ( out of 12 types mil+civ) and wake up in the morning with a happy smile on my face. No 1 Boing 727, No 2 T-38 Talon."

*********************************************************

I was thinking of the T-38 also. Guys would say "it's hard to land" etc, etc. Once you figure it out it was a wonderful flying airplane. Some guys never figured it out and some even quit the program when they could not overcome their fear of the T-38.

727 was easier to figure out.

757's make me smile also. Especially rocketing out of small fields or mountain airports. Nothing like 22-23 degree pitch attitudes on departure. :)

wileydog3

13th Jul 2008, 00:31

Glad to help...

wileydog3

13th Jul 2008, 00:38

I was thinking of the T-38 also. Guys would say "it's hard to land" etc, etc. Once you figure it out it was a wonderful flying airplane. Some guys never figured it out and some even quit the program when they could not overcome their fear of the T-38.

I always thought the -38, the Lear 23 and the 727 were similar in that when you pulled off power, the nose rose slightly. IF you held what you had when the nose came up, it worked out nicely. IF you let the nose move or fall through, it was going to be a firm landing.

Maybe the others did it too but I could hear when the tanker went into ground effect. the sound of the engines changed due to the ground effect and you could literally when you got close to the runway. Probably can't hear it now...

Of all the airplanes I have had the privilege to fly still the most challenging to consistently land good is my 1946 Swift. That little rascal just keeps coming after you and with gusty crosswinds, it focuses my attention like no other airplane. And yes, I know some guys think it is just a sweetheart but with a 90deg cross with 10 gusting to 18kts, it gets my full attention.

The 757/767 were just fat 737s... wake me up after touchdown. I understand the -800 has some tendencies that require a deft touch but the I only did the -200/-300 and -400.

Captain104

13th Jul 2008, 12:57

@ misd-agin
I was thinking of the T-38 also. Guys would say "it's hard to land" etc, etc. Once you figure it out it was a wonderful flying airplane. Some guys never figured it out and some even quit the program when they could not overcome their fear of the T-38.

You hit the nail and must be an insider. Transition from T-37 to T-38 in Williams AFB was critical for some fellows, they had to quit. I remember also the hour required to get used to the "hypersensitive" stick while flying formation. Could you believe: 4 ship formation acro over Arizona! For me, this bird seemed tailored and after the first TO ( 2 instant AB) I decided (even as naval career officer) to fly for all my lifetime- if possible.

Sorry, back to thread. As org and others could understand, the B-727 IMHO is/was the civilian counterpart. Sounds crazy: both aircraft with a kind of soul?!

Regards

767skydriver

21st Mar 2012, 04:19

I have flown those three aircraft, and you could not be more correct.
Good comment.:cool:'

Tee Emm

21st Mar 2012, 13:42

As I recall, as you came across the fence, you eased back on the yoke slightly...as doing so, increasing thrust slightly. Then, as nearing the runway, we relaxed the back pressure...perhaps even pushing a bit on the yoke...and perhaps increasing just a bit more thrust. Such technique resulted on rolling it on at Vref +5 to Vref +10 or so.

I have not flown a 727 so cannot comment with authority on the burst of power technique mentioned. But many times in flying the 737 series I have seen pilots flying a perfectly stable approach and as they flared they would quickly advance the thrust levers a couple of inches giving a burst of power then just as quickly close the thrust levers. It made no difference to the landing impact but merely extended the touch down point.

When questioned about this "technique" they said the burst of power helped cushion the flare. Maybe they had flown the 727 in another life? I was mystified by this nonsense and suggested they were wasting their time since all it did was to increase the float because of the extra speed - which in turn caused the aircraft to land further into the field.

In the 737 it a completely unnecessary maneuver and was often done as a old wives habit. This burst of power at the flare is occasionally seen in the simulator and it is hard to convince some pilots that they are fooling themselves.

One explanation of some of the early spate of 727 high sink rate accidents was the fact that in the airline seniority number system in USA,when a new type was introduced, the unions insisted that the most senior pilots get first crack at the new type. This was because of company and union seniority that also gave them the increased salary associated with any new type.

In those days, most of the older pilots with their high seniority number were previously captains on heavy piston engine airliners like the DC6, DC-3, Stratoliners, Constellations and similar. In other words the cream of the old big radial engines era. These pilots with their thousands of hours on relatively benign aircraft with big propellers, would have run into great difficulty learning an entirely new engine handling technique on jet turbines.

Closing the throttles towards idle on a large piston engine aircraft at 100 feet or higher above the runway, especially with extra speed in hand, would pose no serious danger of high sink rate and loss of energy in a DC-6. Try that in a 727 and a heavy landing was assured. The relatively slow spool up times from closed throttle setting of the early JT8D engines would have caught many senior pilots by surprise.

The danger was the older (seniority reigns supreme, remember) captains of that era would instinctively revert to piston engine throttle handling if high or unstable on late final and reduce thrust far too much for safety in the 727. By then a high sink rate would occur and with no prop blast over the wings to increase lift, the 727 was simply smash into the runway while the engines were spooling up.

A similar type of problem exists today when some older captains convert from well known jet transports like the 737 to the sophisticated flight management and fly by wire operation of the Airbus A320. Some are unable to learn the completely new concept of button pushing since the A320 and similar are automatic pilot dependent from lift off to short final. The actual flying of the side-stick aircraft is easy but the learning experience on highly technical flight management systems can have an overwhelming effect on otherwise highly experienced pilots. So they fail to complete the simulator training.

con-pilot

21st Mar 2012, 18:47

I instructed on this one for 18 years and never saw the 'aircraft develop' an excessive sink rate, only the pilot

And there be the real truth. :ok:

Sir George Cayley

21st Mar 2012, 20:55

But why did crew allow such a departure from the existing sink rate?

Could the reason why Precision Approach Path Indicators were developed have anything to do with it? If you are old enough to remember T-VASIS that were around when ILS and the Jet Age started, you may recall that high sink rates were a problem with T-VASIS when coupled with prop pilots converting to turbo jets.

Worth delving into the archives I think.

SGC

Spotlight

22nd Mar 2012, 01:56

Tee Emm

Not necessarily to disagree, but to hopefully contribute. The burst of power in the flare can be helpful when landing an 800 in gusty conditions. This aeroplane can be unforgiving if in the flare airspeed is trending backwards below Vref.

If encountering localised and difficult conditions. e.g funnel effects when the approach is between hills, water to land, or the tree line starts at the threshold of a runway that is sunken at the end you are using. The burst and chop does help.

On a stable approach on a Wing Commanders day in the 737-800 a trickle of power coming on in the attitude check to hold Vref +5 to ten feet rolls it on every time.

Perhaps you have been finding guys that are reflexive. Flying's not that easy!

Tee Emm

22nd Mar 2012, 06:15

This aeroplane can be unforgiving if in the flare airspeed is trending backwards below Vref.

Of course you are quite right and that applies to most jet transports. The key is not to reduce to idle until into the flare manoeuvre. The "burst" of power is only if a sudden unexpected sink occurs -not because you are slower than you should be at the flare. In the Pacific island atolls where coconut palm trees often surrounded the airstrip it was common to experience significant crosswind windshear at 50 feet below tree level. The runways were short and when coral is wet the touchdown had to be precise and smack on the 1000 ft marker. A wise pilot never cut the power until the first back movement of the flare maneuvre and then cut it quickly as the residual thrust from a spooling down engine could often carry the 737 deeper into the field than desirable.

What I am trying to say and not very well, is the burst of power technique was only used as a last resort if things went ape and the aircraft was dropping out of the sky. It was never meant as a planned specific landing technique for a normal stable approach and landing. If it was, then Boeing would surely have mentioned this under their landing guidelines in the FCTM. There were pilots that gave a burst of power at the flare for every landing because they thought it was a Good Thing. I have watched first officers do a perfectly good approach and just as they flared a twitchy captain would shove open the throttles and back again leaving the first officer wondering what the hell the captain was doing to him.

Spotlight

22nd Mar 2012, 08:16

Thank you Tee Emm

I agree with all you say and hope these posts can be helpful. The 737 is my 3rd Jet and it has taken 700hrs before I could land it to my own satisfaction.

Current, so I know of which I speak. Twitchy Captains still out themselves by the bouncing of the right leg.

CortaVento

22nd Mar 2012, 12:24

Agreeeing with many of the coments above I woul like to add my personal opinion apologizing for my lack of command in english. One must take into consideration the swept of the 727 wing that developped a very poor stability in lower speeds. As many of you recall swept wings develop a lot of induced drag in the low speed region flight needing to increase the angle of attack in order to develop lift (and more drag). The Vref speed is very close to the minimum drag speed and any drop (of speed) induces a further increase in drag needing a lot of power or altitude to trade (sink) to regain speed.This is called the "divergence zone' and the B727 more than any other commercial jet was prone to develop more and more drag as the approach speed decay. I read in a book that the first pilots to fly the B727 used to add some extra knots on the approach speed and this was also because of the stall speed used for certification purposes that taked into account the speed during stall in lieu of the minimum speed with still leveled flight. The pilots that I flew with at that time used to joke that approach speed was "Vref plus two" where 2 means 2 fingers - figure what is two fingers on an analogic IAS... I flew some 6.000hours on the 727 (-100) either as copilot and later as a captain. I enjoyed a lot this machine and consider that it has been my jet handling school for all other aircraft that I flew since then. The combination of these handling carachteristics with the poor engine accelerationn and the lack of previous jet experience of the former captains of the 60's - early 70's probably have been the main cause of many of these accidents and the option to ban the Flaps 40 configuration landing might have been the way to deal with that. This is just my opinion, of course.

aterpster

22nd Mar 2012, 13:53

After the 1965 UAL sink rate crash at Salt Lake City, some airlines made flaps 40 optional on the 727. My airline, TWA, blocked out flaps 40.

I've got a lot of time in both the 727-100 and -200 (more in the -200 by far). I've never heard of the "burst of power" method.

galaxy flyer

22nd Mar 2012, 14:41

I only "wrenched" the Boeing at EAL, but we didn't block out Flaps 40. A couple of times Captains thought it would be nice to let new FOs try a 40 Flap landing. Perhaps, that's why my back hurts in older age. That and the ejection sequence.

GF

trimotor

22nd Mar 2012, 16:49

Flew the 727 extensively, and in operations way beyond the scope of regular airline operations (airshows, formation flying, instruction in the aircraft), including post-maintenance test flying with speeds down to 96 knots to test the stick shakers. F30 and F40 landings. F40 did require a very different landing technique, quite like a turbo-prop flare, with much later power reduction and more developed flare. Abnormally high rates of descent were not a feature of F40 approaches. F40 restriction in many operations was simply noise-related. landing technique could vary between pilots, though conventional landings were easily achieveable, if finely judged, though the late push and roll it on method was easy to do and reliably produced beer-winning results.

As previously mentioned, landing performance, without NLG brakes, could be dramatic...not much over 500m at very light weights.

Due respect had to be made of the lengthy spool-up time for the engines, but considering this, and flying at book speeds, safety was never an issue. High rates of descent could be developed, but were due to lack of anticipation by the pilot, usually resulting in getting a bit slow (typically in the flare) and continuing to raise the nose and letting the 35-odd degrees wing sweep generate a lot of drag, while reducing thrust to land...always a filling-popper.

The whole 'unrecoverable deep stall thing is a myth'. Recovery from the stall could be protracted, granted, but to get there in the first place you would have to have been completely insensitive to the developing problem, starting with the heavy aft elevator input required and pronounced buffet.

It was a fantastic thing to fly, particularly where you had a day out doing visual approaches, and would reward planning and skill. Equally, if you flew like a moron, it showed you up.

TM

PS The comment relating to high climb angles being a result of the T tail is sheer bollocks and ignores basic thrust to weight considerations.

misd-agin

22nd Mar 2012, 19:38

737-800 and 727-200 comparison.

727 w/flaps 30 would be similar to a 737-800 with flaps 35(not as slick as F30, not as bad as F40).

727 w/flaps 40 would have more drag than a 737 w/Flaps 40.

A previous post said it best - flap 40 landings are more like a turboprop, the power stays set until the landing attitude is set, or almost set.

Lots of silly, made up, 727 landing techniques. The worst was the Captain(R.A.) that used to stand the throttles at mid range until the plane touched down. In ground effect I've watched the airplane accelerate. Beyond dumb.

New FO's would ask what technique I use - "power starts coming back at 10', idle before touchdown. I don't recommend you do that until you're more comfortable with the airplane. Don't get slow, keep the power steady until right before touchdown. As you get experience you'll realize you can reduce the power sooner."

It was less forgiving then the 737NG/757/767/777 but it wasn't some monster with three heads. Touchdown smoothness was very similar to a A300. You'd think you had it nailed and the plane would say - "no, not quite good enough." Drift and crab are easy ways to reduce the 'quality' of the touchdown to a degree more severe than the 737NG/757/767/777 punish you for lack of perfection.

aterpster

22nd Mar 2012, 23:31

gf:

I only "wrenched" the Boeing at EAL, but we didn't block out Flaps 40. A couple of times Captains thought it would be nice to let new FOs try a 40 Flap landing. Perhaps, that's why my back hurts in older age. That and the ejection sequence.

The FAA or NTSB recommendation was to use flaps 30 normally, and only use flaps 40 if necessary. TWA elected to block out flaps 40. So far as I know most carriers did not. We flew National 727-200s one or two summers on a summer/winter exchange. They did not have flaps 40 blocked.

topgas

25th Mar 2012, 20:44

Comparison has been made on this thread between the 727 and VC10. One thing that has always struck me, as SLF, is that the VC10 doesn't really flare on landing - it seems to point the nose at the threshold and level up just before touchdown This video shows what I mean
Royal Air Force VC-10 landing and take-off - Hannover Langenhagen - YouTube
I presume that they don't do this just because the passenger seats in RAF VC10s face backwards. Is it in fact quite different from a 727? Apologies for thread drift

aterpster

26th Mar 2012, 12:07

I sure saw a flare there.

stilton

26th Mar 2012, 22:27

Tri Motor and Misdagain are completely correct.

Deep stall was never an issue.

And there were loads of silly landing techniques and myths as to why.

You had to watch you sink rate carefully, if you let a high rate develop you did need power and lots of it quickly.

However, you could flare and land normally with idle power, and this, as with most jets is optimal.

F40 was blocked at my Airline and most US operators.

galaxy flyer

26th Mar 2012, 23:46

EAL's 727s weren't blocked at 30 and Flaps 40 landings were at the discretion of the captain except at KEYW where 40 was mandatory. 4,800 feet of LDA. The standard was 30, however.

GF

aterpster

27th Mar 2012, 14:49

IGh:

Then I checked an old TWA FHB for their B727's, pagedate May 1977, Controls & Indicators, still shows the F40 position (withoutany mention of a Gate-Blocker for F40).

Maybe someone canfind an old Recurrent Train Bulletin describing DATE of the INITIALMODIFICATION that blocked B727's F40 [my guess is that modification was a FUELCONSERVATION measure after the price of fuel doubled between April and Augustof 1979 (????)].

Below is a none-too-good photo of the flap lock-out block. Note it is held in place with two screws. This photo is a clip from a photo of me and a good friend en route in a TWA 727-100 in the early 1970s, if memory serves me correctly. I believe itwas 1972.

Also, I am not sure the FHB would have ever shown the block. If the FHP you have is complete check the flight profile illustrations. They would show selection of Flaps 30 as final landing flaps.

http://i201.photobucket.com/albums/aa214/aterpster/TWA727Flaps40block.jpg

aterpster

27th Mar 2012, 18:49

IGh:

Thanks -- I had no doubt that line-pilots heard their Ground School Instructors spread that rumor about the company's MOTIVE for blocking F40 [recall that various airline Ground Schools propagated the "Boeing Scenario" (a rumored high altitude CRZ configuration) after the 4Apr79 mysterious inflight upset of a B727-31]. Human instructors were entertaining (now pilots get CBT without the entertaining ad lib's of a human ground school instructor). [The Boeing Rep' at at TWA's K.C. HQ related to me the the "Boeing Scenario" began right there in K.C., over the back-fence, and was then reported back to Seattle. Rumor can force investigator-err, when desired by that once overpowering manufacturer.]

The Detroit "swan dive" happened long after TWA blocked out Flaps 40. I checked out in late 1968 and the block was already in place. It wasn't when I went through F/O school on the 727 in late 1964.

I just verified with another retired TWA pilot that the block was in place by late 1968. I also recall being instructed that it was because of the 1965 UAL KSLC accident and, additionally, Flaps 40 was a lot of drag for the early stages of an ILS missed approach.

When fuel savings became an issue the company reduced Mach cruise by a fair amount and added a performance monitor. The also changed the climb schedule.

I was still flying the 727 when Captain Gibson made his dive over Detroit. Nothing was mentioned about it to any recurrent ground school or simulator session I attended. I flew that airplane shortly after it was returned to service. The ripples on the lower aft fuselage were "interesting" to say the lease.