Trident Pilots

[Surtchris]

PAXboy if you’re around and anybody else who can help. I have now read all 92 posts but I think this thread may have gone off the radar - last post 24th July. I found it very interesting. I used to fly quite a lot on business on Tridents and, I must say, I am glad I hadn’t read this thread when I did. It all sounds a bit sketchy. The Trident, I gather, was quite a handful unless you knew what you were doing and according to information provided on this thread some captains didn’t.

The Papa India crash was the most horrific airline disaster and I still have vivid memories of the subesequent press coverage. I lived in Maidenhead, as I believe did Simon Ticehurst, and we were the same age. I was friends with three Hamble cadets; we used to fly together in a Cherokee 140 from White Waltham. A few anxious hours before I found out none of them were involved as they were all by then first officers. They went onto to become captains and one a fleet captain but presumably they have now retired.
I do realise that this crash has been done and dusted in a previous thread and many would prefer to move on and forget it. I found one post particularly distressing concerning Jeremy Keighley’s mother who said ‘surely my son didn’t kill all those people’. I picked up on something a few years ago which has been nagging at the back of my mind ever since and whilst I know airline professionals, pilots and others, don’t like amateurs commenting on airline business I would appreciate it if somebody could humour me and at least put my mind at rest.

Unfortunately neither the Lane Enquiry nor the threads deal with my specific issue. I can only repeat the Aileron Drag post - Ex Gripper pilots- Help. May I ask Gripper pilots to be kind enough to spend a few minutes of their time to take a trip down memory lane and look at the flight deck of the Trident by visiting http://en.wikipedia.org/wiki/File:TridentFlightDeck.JPG. There is a full resolution option which gives a detailed view of the Trident flight deck.
For twenty years I ran my own consultancy company which provided consultancy advice to companies trading in many corporate areas including engineering, management training and quality assurance. I was also involved in couple of aviation projects including working with a company that operated a BAC1-11 from Heathrow in a twenty five seat executive jet configuration. Fun times including a memorable full power take off on a windy day from 27R in a Gulf Stream Four with four of us on board. As the training captain said afterwards, ‘Did we go up!’
I had a reputation on occasions for what some might have perceived as fixating but usually, not always, apologies were in order when folk discovered I was right. I certainly do have a problem with the Papa India disaster, as I didn’t believe at the time and, having read the Lane enquiry recently, I still don’t believe that anybody on the flight deck selected to withdraw the droop flaps shortly after take off, speed 170 knots with the aircraft banked and in heavy turbulence. The Lane enquiry commissioned by Michael Heseltine on 19th June 1972 was a public enquiry presided over by High Court Judge Sir Geoffrey Lane. The enquiry swiftly deteriorated into a Fred Karno show as a result of litigious interests, with lawyers interfering in an unprofessional way with proceedings, and media hype because the enquiry was held in the public arena. One AIB inspector committed suicide probably as a result of the pressures involved and some of the recommendations bordered on the absurd.
All of which brings me back to the Trident cockpit because I am sure that some other factor was involved in this accident that did not surface at The Lane Enquiry. At first sight the droop flap lever, and its position in relation to the auto pilot height select panel, looks like an accident waiting to happen. The problem is that I didn’t operate these levers or sit in the Trident cockpit and only a Trident pilot can check me out on this and verify whether I am making a valid point. The right hand lever operating the trailing edge flaps is fit for purpose because it is an incremental lever with five settings, flaps up, flaps 10%, 15%, 23% and full flaps for landing. The droops lever was housed on the left under the same metal cover and, if this picture of the cockpit gives me a proper perspective, this lever was not fit for purpose because it appears to have to travel the same length as the incremental lever. The droop lever has to be pulled with nothing happening until it reaches the end of its travel and is locked into place over/under the spring strut, which initiates droop flap extension. Conversely when retracting the flaps the lever had to be pulled all the way back to the droop flaps up position, which apart from being a waste of effort, could cause problems if the lever was knocked out of position, as it might appear to the pilots, particularly in turbulence with the plane bumping about, that the droops were extended when they had retracted. As a point of design principle a one function lever, droops up/droops down, like an undercarriage lever shouldn’t have any travel. Looking at the lever arm its width appears to be about half an inch but it is hard to tell. My primary concern is how far back up the travel would this lever have to go before the droops retracted and wouldn’t this leave the lever still looking as if the droops were extended; unless the design guys fitted some sort of spring/hydraulic mechanism which put the lever back to the up position (retracted) if the pilot didn’t push the lever all the way back to its up (retracted) position.

The height select panel is positioned to the left of the droop lever and when the droops are up (retracted) the lever is above the height select panel but when the droops are down (extended) the RHS pilot, who would normally input altitude selection because the height select panel is on the right of the centre console, has to operate over the droop lever to input altitude selections and his hand /wrist are above the lever. Remembering a particularly bumpy approach to Luton on a Ryan Air turbo prop my arms were knocked of the seat rest and it isn’t difficult to imagine the difficulties in turbulence that would be experienced by the RHS pilot to input altitude selections in turbulence while the droops are down (Extended).

Over the years I have spoken to quite a few airline captains about the Papa India disaster and all seem to agree that what happened was that Captain Stanley Key following re clearance by ATC from 1500ft to 6000ft told P2 Jeremy Keighley to put it in and because Keighley was inexperienced he mistook Key’s command to mean retract the droop flaps. This theory was also advanced at the Lane enquiry. Basically this theory doesn’t work because if Keighley had pushed the droop lever up to retract the droops this would have been noticed by P3 Simon Ticehurst (who was more experienced and supervising Keighley) and Captain John Collins in the observer seat and as within seconds the stall warning horn, warning lights and stall recovery systems activated they would have been immediately alerted to a critical airspeed situation and would have checked the droops and extended them again. This also applies to Key who was supposed to be having a heart attack (medical opinion on Keys health at the enquiry was wildly divergent at worst it appears that Key might have been suffering from some discomfort like heartburn.) but if Key had retracted the droops the same applies the droops would have been extended again.

My hypothesis, as Aileron Drag puts it, is that Keighley did not mistake the command but did exactly as he was told and put in presumably, as it was a four digit input 06.00 into the height select panel but while he was twisting the knob due to the turbulence he knocked the lever out of position and the droops retracted but this was not visible to the other pilots. This is why no stall recovery procedures were initiated and why all the pilots assumed the stall recovery systems had activated without reason and why Key dumped the stall recovery systems and carried on trying to climb the aircraft. My hypothesis appears also born out by, I am afraid, by a rather grim piece of information. Captain John Collin’s body position in the cockpit after the crash indicated that he was leaning forward staring at the centre console and sources close to events suggest that he was the one that actually locked the lever back into place. I assume because he had taken a closer look at the droops lever and had seen what the problem was and extended the droops again but sadly too late.

This seems to be a good point to wind up and see if any Trident Pilots think my explanation of events could have any validity. If they do this raises other questions about the enquiry itself more appropriate for another post and, of course, the cause of the crash was not pilot error but a fundamental design/layout fault in the Trident cockpit.