Trident autothrust system and autoland
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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? 
I can see this as being a minor pain to convert to/from Tridents.
I can see this as being a minor pain to convert to/from Tridents.
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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
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!
Concorde Style Yoke — Tech Ops Forum | Airliners.net
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!
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Edit...sorry Slast...Crossed!
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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.
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.
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.
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.
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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?
....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?
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... 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.
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.
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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. 
)
)
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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.
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.
Last edited by Hobo; 7th Dec 2010 at 19:47. Reason: sp
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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/powerpo...n_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
Nice to speak to you again "A"...Surprised to find this much interest in the old Trident.
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..............
(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..............
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.
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.
67 mb for those who have bandwidth limitations. Interesting photos of East Africa. Half those cars look pre-war.
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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!
Oh yes, it has music so you might want to turn the volume off or up according to taste!
switches in standard positions
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!
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!
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.
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.
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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
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
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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