BCAL From United Kingdom, joined Jun 2004, 3384 posts, RR: 25 Posted (1 year 10 months 4 weeks 1 day 7 hours ago) and read 6659 times:
Last year I wrote a tribute to the Hawker Siddeley Trident and emailed this to Wings to include as one of his future tributes asking him to add pictures and diagrams (something that I cannot quite master!). It never appeared on the threads. Inspired by the recent threads on Trident, and to make a refreshing change from posts about Boeings and Airbuses, I thought it would be appropriate to post the thread and relive a little nostalgia.
LHR was a different picture in the 1970s. You could go on the spectator balcony on Queen's Building and the sight that normally greeted you was as shown below with hardly a Boeing in sight and Airbus had yet to make an appearance.
What is fascinating about the Hawker Siddeley (née de Havilland) Trident is how it ended up achieving minimal success despite the huge potential that was seen for its revolutionary design when first launched in the late 1950s. As with many other British Civil Aviation aircraft, Trident was marred by the fact that the designers and manufacturers bent over backwards to meet the criteria laid down by BEA (now BA) for a passenger jet aircraft planned to accommodate circa 100 passengers on short to medium-haul services throughout Europe. Matters were not helped by the constant interference of the UK Government in the aircraft’s development.
Origins
In July 1956 BEA issued a requirement for a 100-seat +600mph jet airliner capable of carrying a payload of up to 19,000lbs out of 6,000ft runways over 1,000 mile-sectors. A further requirement was that the aircraft should have “more than two engines”. De Havilland decided to cater for BEA’s requirements and conceived the ‘Model 121’ in May 1957. Model 121 was a larger aircraft than that envisaged by BEA, with larger capacity, range, and more-powerful engines. It competed with other models being designed by Vickers, Bristol, and A V Roe & Co, other British aircraft manufacturers of the time. To win the order, de Havilland reduced the capacity, range and other features of the aircraft so that it was tailor-made for BEA’s requirements with less powerful power plants. BEA signed a purchase contract on 12 August 1959 for 24 aircraft plus 12 options valued at GBP 28 million. Exactly one month after this order, Boeing finalised the design of its aircraft that went on to become the 727.
Production and Development
Production of the Trident commenced on 29 July 1959 with the first flight scheduled for December 1961. Deliveries to BA were scheduled to take place in three batches between late 1963 and 1966. In December 1959 de Havilland merged with Hawker Siddeley, another British aviation company, which took over Trident’s development.
The first Trident (registered G-ARPA), model 1C, was towed out of the workshop on 4 August 1961 minus power plants, revealing an distinctive offset nose gear with a twist and turn nose gear retraction sequence. After flight testing on a Vulcan B1 bomber the engines (Rolls Royce Speys) were fitted to G-ARPA in November 1961. G-ARPA was cleared for its maiden flight on 12 December 1961 but bad weather delayed this until 9 January 1962. The second Trident took to the air on 20 May 1962. Because of the experience with de Havilland’s Comets, Trident was subject to thorough flight testing. Hot weather trials took place in the Middle East from November 1962. Trident was found to have a problem in that it tended not to exhibit the classic nose-down pitch at stall. High speed trials completed in April 1963 when it was revealed that high cruise speed was Mach 0.88 and 0.96 in shallow dives at altitudes between 24,000 and 30,000ft.
In February 1964 the Trident received its Certificate of Airworthiness after some 1,600hr of flight testing. The fifth production Trident was delivered to BEA on 19 February 1964 and the airline planned to have three Tridents in service by 31 March. After the aircraft had been in service for several months, its performance was found to be below par on some BEA sectors. BEA conceded that the Trident could not operate with a full load on certain routes, either because of runway limitations and obstacles, or hot temperatures. The aircraft’s range was insufficient for non-stop operation on some routes (e.g. LHR-ATH). Consequently, more powerful engines were specified for later production models.
As previously stated the Trident 1C was only suited for BEA’s operations, and even then with some limitations. To achieve export sales, Hawker Siddeley realised that they had to develop a significantly improved version, the first of which was revealed in January 1960. The first foreign airline to express any interest in this aircraft was Trans Australia Airlines (TAA). In December 1960 another version of the Trident, designated Trident 1A, was proposed to meet the requirements of US carriers. This had an increased MTOW and an enlarged wing incorporating improvements for field performance and aimed primarily at American Airlines. Neither TAA nor any US airlines placed any orders. On 8 August 1962, Kuwait Airways became the Trident’s second customer when it signed an order for two aircraft (Trident 1E) with a further option. Iraqi Airways became the second export customer on 1 October 1963 with an order for three aircraft, followed by PIA on 26 January 1964 also for three aircraft. Variants of the Trident 1E were developed and produced, winning small orders from now-defunct British regional and charter airlines, Channel Airways and BKS Air Transport. Air Ceylon also ordered a Trident that was delivered in July 1969.
As the Tridents 1C were being introduced in BEA service, the airline realised the need for a developed version of the aircraft, capable of flying London-Beirut non-stop with a full payload. Trident 2E was developed to meet this criteria. BEA signed an order for 15 aircraft + 10 options was signed on 5 August 1965 with delivery from 1968. The 2E featured an increased gross weight, more powerful Spey engines, an extra full tank in the tail, and reduced drag by fitting special low-drag ‘Kuchermann’ wing-tips.
At the end of June 1966 BEA sought government approval (the airline was then state-owned) to acquire up to 35 727s and 737s for delivery from 1968. The then Labour Government insisted that BEA should “buy British” which led to Hawker Siddeley designing a stretched version of the Trident 2E – the Trident 3B. However, the Trident’s existing power plants were insufficient for the planned stretched version resulting in Hawker Siddeley and Rolls Royce seeking a government grant for development of a new more-powerful power plant. The grant was refused. As the Speys had reached their maximum power without significant redesign, the problem was solved by mounting a RB 162 take-off booster engine just above the centre engine, so effectively the Trident went from a three-holer to a four-holer. The Trident 3B was rolled out on 17 November 1969 with the first flight taking place a month later. Deliveries commenced to BEA in February 1971 and the first revenue service took place on 1 March 1971.
PIA sold their Tridents to the CAAC who were impressed with the aircraft’s performance. As the Chinese were then forbidden to buying US goods, they placed orders for 35 Trident 2E aircraft, and became the Trident’s largest export customer, second only to BEA. They went on to provide a reliable service with CAAC and a number were transferred to the air force and took up military service.
The Trident, as completed, was the first passenger jet with the T-tail configuration, the first in the world with three rear-mounted engines and the first capable of all-weather operations.
The Boeing 727 (which went on to achieve the success that bypassed the Trident) bore many similarities to the original plans for the Hawker Siddeley 121 before being down-sided. This could be explained by the fact that during the early days of the Trident's development a consortium of Boeing engineers and designers were invited by de Havilland to visit Hatfield and share knowledge gained on the aircraft's design and development.
One of the designs for a successor to the Trident, announced in 1967 but which never got further than the drawing board, shows a striking resemblance to the Boeing 757.
Trident was the first commercial passenger jet configured for autoland. Towards the end of the 1970s, when the majority of aircraft including “new” 737s were grounded at fog-bound European airports, BEA’s Tridents were able to maintain their schedules due to having autoland installed on the entire fleet.
The Trident shared the honour with the Convair 990 of being the fastest subsonic airline in service.
It was the first airliner to be approved with duplex flight control system.
It was the first civil aircraft to be installed with Cockpit flight recorders (something that would have greatly helped the investigators find out exactly what happened when Trident G-ARPI stalled after take off from LHR on 18 June 1972)
Trident formed the backbone of BEA’s fleet in the late 1960s and 1970s.
Trident had an excellent rate of descent, and the aircraft often descended quicker than the cabin pressure could be adjusted. Although never confirmed, some BEA pilots admitted that they had occasionally flown Trident at Mach 1
Another unique character of Trident was that on some landings reverse thrust could be deployed before the wheels made contact with the runway.
Downsides
Trident was remembered for the considerable amount of noise it generated, particularly by people living near LHR. A.net members have often mentioned how noisy the BAC 1-11 was but what they do not realise is whereas the BAC 1-11 had two Rolls Royce Speys engines, Trident had three and Models 3B also had the additional booster engine.
Tridents were relatively underpowered. It was a common joke amongst BEA pilots, who gave the aircraft the nickname “Gripper” (as it often seemed to grip to the earth’s gravity), that Tridents only became airborne due to the earth’s curvature! However, once in her element, Trident was like a jet fighter.
Accidents
The first Trident accident occurred during testing on 3 June 1966. The Trident, in common with other T-tail jets, suffered from deep stall problems. Part of the pre-delivery checks involved stalls in various configurations, some with protection systems operating, others with two systems inhibited. In the latter case Trident G-ARPY entered a deep stall commencing at a height of 11,600ft but as she started to pitch down when the airspeed began to drop off rapidly and the nose down motion ceased and the aircraft then entered a deep stall. The nose was seen to pitch up 30-40 degrees and the aircraft began to turn to port as she descended slowly. The starboard wing then dropped suddenly and following a short burst of engine power, the aircraft began to stall rapidly in a flat spin to starboard, turning once every 6-8 seconds. The aircraft impacted the ground 90 seconds later, breaking apart, and killing all four crew.
On 3 July 1968, a BKS Airspeed Ambassador went out of control whilst taxiing at LHR and collided with two parked Tridents, causing considerable damaged to both parker aircraft. One Trident (G-ARPT) was written off, as the cost of repairs exceeded the cost of replacing the aircraft, but the other (Trident G-ARPI) was repaired and returned to service.
On 18 June 1972 G-ARPI was operating a BEA service from LHR to Brussels. Due to a strike at Sabena, all 109-seats were full on this flight as well as the flight ferrying off-duty crew, 3 pilots, and 3 F/As. After a normal take-off the aircraft climbed to 1,800ft but then “fell out of the sky” and crashed into a field near the airport killing all 118 on board. The UK AIB found that the aircraft’s leading edge drop high lift device had been retracted at 162kt, around 60kt below the safe droop retraction speed of 225kt. As a result, the aircraft entered a “change of configuration stall” that led to a deep stall from which recovery was impossible. Who retracted the leading edge drop high lift device is not known, but it was found that the captain of the aircraft, who had previously had a heated argument with another pilot before taking command of G-ARPI, was suffering from a very severe heart condition and might therefore had had a heart attack that impaired his judgment. The co-pilots were both very young and inexperienced.
On 10 September 1976 a BA Trident 3B was cruising at 33,000ft en route from LHR to IST was involved in a mid-air collision with an Inex Adria DC9 flying from Split to Cologne. The outer 15ft of the DC9’s left wing smashed through the forward fuselage and cockpit of the Trident killing the flight deck crew instantly. The Trident then plummeted to the ground out of control, killing all on board. The DC9 also went out of control and partly broke up as its left wing erupted into a fireball. All 113 people on board the DC9 perished. The accident was blamed on improper air traffic control operation.
A CAAC Trident 2E crashed on landing at Hong Kong’s Kai Tak Airport on 31 August 1988. The aircraft was too low on approach and struck approach lights causing it to run out of control and fall over the edge of the runway. The majority of passengers survived but the flight deck crew perished.
As will be seen, no accidents in the commercial life of Trident can be attributed to the design and/or malfunction of the aircraft. The LHR accident was contributed to pilot error, the Zagreb to ATC, and Kai Tak again to pilot error.
Finally, some posters in the earlier forum mentioned that seats in the Trident and space was cramped. Whilst this might be true for the Channel Airways Tridents (where the seating configuration in the front cabin was 4,3), you should remember that Trident was a successor to the Viscounts, Vanguards, Comets and Caravelles and in comparision seemed very roomy. Here is the closet shot that I could find of a cabin of a BEA/BA Trident (I could not find any photographs of the cabin whilst in service with BEA/BA).
Photo used by permission of Ian Haskell (PlanePictures.net)
MOL on SRB's latest attack at BA: "It's like a little Chihuahua barking at a dying Labrador. Nobody cares."
Bennett123 From United Kingdom, joined Aug 2004, 4623 posts, RR: 2 Reply 3, posted (1 year 10 months 4 weeks 1 day 5 hours ago) and read 6521 times:
I assume that you are suggesting that the deep stall problems are not the ultimate cause of the loss of G-ARPY and G-ARPI when you say that "As will be seen, no accidents in the commercial life of Trident can be attributed to the design and/or malfunction of the aircraft. The LHR accident was contributed to pilot error, the Zagreb to ATC, and Kai Tak again to pilot error".
IMO the loss of G-ARPY was linked to deep stall, (although not in commercial service) and whilst G-ARPI was argueably caused by Pilot error, the issue of deep stall and the T tail are surely major factors as well.
ExFATboy From United States of America, joined Jul 2003, 2230 posts, RR: 9 Reply 4, posted (1 year 10 months 4 weeks 1 day 5 hours ago) and read 6507 times:
Great tribute! It's a shame, really - if she'd been built to the original specs, sales probably would have been a lot greater and the history of the UK commercial aviation industry could have been quite different.
(BTW, the PlanePictures.net pic is showing the Red X Of Doom right now, sorry to say...)
NWOrientDC10 From United States of America, joined Mar 2005, 1363 posts, RR: 5 Reply 6, posted (1 year 10 months 4 weeks 1 day 4 hours ago) and read 6402 times:
Quoting BCAL (Thread starter): The Trident, as completed, was the first passenger jet with the T-tail configuration, the first in the world with three rear-mounted engines and the first capable of all-weather operations.
The Boeing 727 (which went on to achieve the success that bypassed the Trident) bore many similarities to the original plans for the Hawker Siddeley 121 before being down-sided. This could be explained by the fact that during the early days of the Trident's development a consortium of Boeing engineers and designers were invited by de Havilland to visit Hatfield and share knowledge gained on the aircraft's design and development.
I think the Trident, like the B727, had retractable stairs. The Trident's stairs, however, were located at the forward port side door (I have not looked this up yet, so this may be incorrect.). If the Trident did have its own retractable stairs, were there some constructed with the stairs located at other exits (maybe at an aft exit)?
Quoting BCAL (Thread starter): BEA conceded that the Trident could not operate with a full load on certain routes, either because of runway limitations
Alaska Airlines operated some of it's 727's on gravel runways. Was the Trident capable of similar operations?
Quoting BCAL (Thread starter): Neither TAA nor any US airlines placed any orders.
No Trident saw service in the US
Also, I think the Trident looked good in this livery:
This is a good discussion topic. Thanks for writting it
BCAL From United Kingdom, joined Jun 2004, 3384 posts, RR: 25 Reply 7, posted (1 year 10 months 4 weeks 1 day 4 hours ago) and read 6367 times:
Quoting Bennett123 (Reply 3): IMO the loss of G-ARPY was linked to deep stall, (although not in commercial service) and whilst G-ARPI was argueably caused by Pilot error, the issue of deep stall and the T tail are surely major factors as well.
Quote: To prevent line pilots from getting into the deep stall (which was characteristic of all T-tail rear-engined aircraft) de Havilland fitted a stick shaker and stick pusher system to the Trident's control columns. The former was a device that rattled the stick to warn that a stall was approaching, whilst the latter incorporated a pneumatic ram that physically pushed the stick forward to lower the nose. The Trident was the first airliner to be certificated with a stick push system.
Source: Classic Civil Aircraft - Hawker Siddeley Trident, 1993 Max Kingsley-Jones p 113
IIRC according to the accident investigation on G-ARPI the leading edge droop high lift device had been retracted around 60kt below the safe droop retraction speed of 225kt and the stick shaker had been over-ridden.
Quoting ExFATboy (Reply 4): BTW, the PlanePictures.net pic is showing the Red X Of Doom right now, sorry to say
Noticed that too. Permission was obtained from the photographer and it appeared earlier, but here is the link
MOL on SRB's latest attack at BA: "It's like a little Chihuahua barking at a dying Labrador. Nobody cares."
BCAL From United Kingdom, joined Jun 2004, 3384 posts, RR: 25 Reply 8, posted (1 year 10 months 4 weeks 1 day 4 hours ago) and read 6346 times:
Quoting NWOrientDC10 (Reply 6): I think the Trident, like the B727, had retractable stairs
I believe that Hawker Siddeley/De Havilland offered retractable stairs as an optional extra on the Trident 1E but AFAIK no airline took up this option.
MOL on SRB's latest attack at BA: "It's like a little Chihuahua barking at a dying Labrador. Nobody cares."
Bennett123 From United Kingdom, joined Aug 2004, 4623 posts, RR: 2 Reply 9, posted (1 year 10 months 4 weeks 1 day 4 hours ago) and read 6336 times:
But the stick shaker and stick pusher were surely installed as a result of the Deep Stall issues of T tails and the fact that in a stall the control surfaces on the tail are ineffective due to the "shadow" of the wings.
BCAL From United Kingdom, joined Jun 2004, 3384 posts, RR: 25 Reply 10, posted (1 year 10 months 4 weeks 1 day 3 hours ago) and read 6293 times:
Quoting Bennett123 (Reply 9): But the stick shaker and stick pusher were surely installed as a result of the Deep Stall issues of T tails and the fact that in a stall the control surfaces on the tail are ineffective due to the "shadow" of the wings.
Correct. The subsequent investigation concluded that G-ARPY's accident was due to deep stall (although as you said she was not in commercial service at the time) and according to the test schedule the two stall protection systems were inhibited. In the case of G-ARPI, from what I have been told if the drop retraction had not been executed in error, she might not have entered a deep stall, as similar incidents from which the aircraft recovered had been reported previously, most notably G-AVFH bound for Naples from LHR on 8 May 1970.
MOL on SRB's latest attack at BA: "It's like a little Chihuahua barking at a dying Labrador. Nobody cares."
Bennett123 From United Kingdom, joined Aug 2004, 4623 posts, RR: 2 Reply 11, posted (1 year 10 months 4 weeks 1 day 3 hours ago) and read 6230 times:
Clearly, the droop retraction is a major factor in the loss of Papa India.
However, the point that I am making, (I believe validly) is that IMO your assertion that no accidents can be attributed to design weaknesses is somewhat generous.
Dc863 From Madagascar, joined Jun 1999, 1504 posts, RR: 4 Reply 12, posted (1 year 10 months 4 weeks 22 hours ago) and read 6101 times:
Quoting Bennett123 (Reply 11): Clearly, the droop retraction is a major factor in the loss of Papa India.
Which came at a point when the speed had deteriorated 25 kts since rotation. None of the flight crew including the Vanguard Capt. in the jumpseat noticed.
TristarSteve From Sweden, joined Nov 2005, 2905 posts, RR: 23 Reply 14, posted (1 year 10 months 4 weeks 21 hours ago) and read 6047 times:
Quoting BCAL (Thread starter): the problem was solved by mounting a RB 162 take-off booster engine just above the centre engine, so effectively the Trident went from a three-holer to a four-holer.
This engine was built for a VTOL aircraft. It was extremely light. All the compressor was made of glass fibre including the blades. It had a total loss oil system. Because of this it had a very limited run time. It was started on the taxi out, and automatically went from idle to take off when two throttles were advanced. It was noisy! Because the RB162 was placed where the APU was, the APU on the T3 was moved up above the centre engine S duct intake. Good access on the line!
Quoting BCAL (Thread starter): It was the first airliner to be approved with duplex flight control system
It had a triplex control system. There were three hydraulic systems, and every primary control surface had three actuators.
Quoting BCAL (Thread starter): revealing an distinctive offset nose gear with a twist and turn nose gear retraction sequence
The nose gear retracted sideways. However the Main gears rotated by 90deg as they retracted.
Quoting BCAL (Thread starter): Another unique character of Trident was that on some landings reverse thrust could be deployed before the wheels made contact with the runway.
The thrust reversers could be deployed in flight, and were regularly used to slow the rate of descent.
Quoting BCAL (Thread starter): The UK AIB found that the aircraft’s leading edge drop high lift device had been retracted
The droop leading edge was only used on the T1C. Later models had conventional slats. The main difference was that there was no slot. It was very effective. The original design had two levers, one for flaps, and one for droop. After the Staines accident the levers were connected by baulks so that the droop could not be retracted before the flaps.
Quoting BCAL (Thread starter): One Trident (G-ARPT) was written off, as the cost of repairs exceeded the cost of replacing the aircraft, but the other (Trident G-ARPI) was repaired and returned to service.
Note that this was the Staines accident aircraft. Large parts of RPT were used in the repair of RPI including the whole tail section.
Quoting NWOrientDC10 (Reply 6): I think the Trident, like the B727, had retractable stairs.
I never saw a Trident with airstairs.
The Trident was my first aircraft. I worked for BEA from 1968 to 1976 and got my first Engineers licence on the Trident.Spent many hours up the hatch at the back where all the hydraulics and air conditioning was fitted.
Viscount724 From Switzerland, joined Oct 2006, 11645 posts, RR: 13 Reply 15, posted (1 year 10 months 4 weeks 20 hours ago) and read 6022 times:
Quoting ExFATboy (Reply 4): Great tribute! It's a shame, really - if she'd been built to the original specs, sales probably would have been a lot greater and the history of the UK commercial aviation industry could have been quite different.
I flew on BEA Tridents several times. The Trident was in many ways ahead of its time technically but it suffered from the same problems that affected too many British airliners of that era. It was largely designed to meet the requirements of one airline,which meant that it wasn't very attractive to other carriers and sold only in very small numbers to carriers other than BEA. It also suffered from the other chronic British airliner problem of taking too long to go into service.
The Trident took more than twice as long as the 727 between first flight and first service. The 727 first flew more than a year after the Trident but was in service two months before the Trident.
The same problem affected the BAC1-11 which took 20 months from first flight to first service, while both the DC-9 and 737 were in service within 10 months of their first flights. At least the 1-11 was designed with a wider market in mind and thus sold in larger numbers than the Trident.
The VC-10 had a similarly long gestation period as did several earlier British designs, notably the Britannia which took 4.5 years from first flight to first service, by which time the 707 was only a little over a year away.
TristarSteve From Sweden, joined Nov 2005, 2905 posts, RR: 23 Reply 16, posted (1 year 10 months 4 weeks 18 hours ago) and read 5978 times:
Quoting Viscount724 (Reply 15): The Trident took more than twice as long as the 727 between first flight and first service. The 727 first flew more than a year after the Trident but was in service two months before the Trident.
We must remember that the Trident was a very complicated aircraft. This stems from the Autoland requirement that introduced the triple systems.
Why was this so important to BEA. I lived in London in the late 50s early 60s when the Trident specification was set up. London suffered from Smog. Most houses had their own coal fires, and in the autumn the smoke from these fires rose up and got trapped. The result was Smog. This was fog full of soot. It could be dense. There were times that this Smog would last two weeks. This grounded all aircraft. I remember in about 1960 walking along the pavement at midday, so my Dad could drive our car behind me. He could not see the edge of the road from the drivers seat. So BEA asked for Cat3 autoland, and de Havilland supplied it. The Smiths Autoland system was a big analog triple channel computor set in the centre consol behind the throttles. It had a very low MTBF and needed constant maintenance. And this was before BITE was invented. The powered flying controls had three servos each and stuck strut detectors in triplicate to keep them working. It was complicated.
The first B737 had a twin hyd system (with a small standby rudder system) and a single autopilot. The elevator and aileron controls were manual with hyd boost. The original single channel autopilot was only Cat1 with no autoland. Of course it was developed quicker, there was a lot less of it. (Later B737-200 had dual channel autopilot)
BCAL From United Kingdom, joined Jun 2004, 3384 posts, RR: 25 Reply 17, posted (1 year 10 months 4 weeks 16 hours ago) and read 5924 times:
Quoting Bennett123 (Reply 11): However, the point that I am making, (I believe validly) is that IMO your assertion that no accidents can be attributed to design weaknesses is somewhat generous.
I am happy to accept your valid point.
Quoting Dc863 (Reply 12): Which came at a point when the speed had deteriorated 25 kts since rotation. None of the flight crew including the Vanguard Capt. in the jumpseat noticed.
Nobody knew exactly what happened on the flight deck of G-ARPI after take off, as cockpit voice recorders were then not installed (it was after this accident that they became compulsory). The captain (Stanley Key), who according to a post mortem examination was suffering from a heart condition which was likely to be causing him some pain immediately prior to the crash, was the handling pilot. He was assisted by two relatively inexperienced second officers, S/O Keighley (in P2 on starboard side)) and S/O Ticehurst (in central P3 position). Captain Collins, the off-duty Vanguard pilot, was in P4 or the jump seat behind the captain.
In those days BEA S/Os had to get much of their experience 'on-line' and the progress of their careers was very much dictated by reports from captains with whom they flew. Captain Key, being one of the 'old captains' was rumoured to be against training pilots this way and he often had clashes with management and colleagues, so he was 'feared' by the young trainees. Both S/O Keighley and S/O Ticehurst had witnessed Key's outburst in the staff room before the flight, so the CSM on that flight deck would have been very low. Ticehurst should have been monitoring the flying pilots and according to the AAIB report if on the accident flight the monitoring system had worked as it should, the great speed errors would have been noted by both pilots - and by the P3. S/O Ticehurst should, as one witness put it, have been
almost literally screaming 'Speed!' at the Captain.
Whether the captain sitting in the jumpseat was aware of the crew's errors, the slow reactions of the S/O, or the captain possibly becoming incapacitated, will never be known. However, in the AAIB it was stated that his presence on the flight deck, which served no useful purpose, was probably the main course of S/O Ticehurst's wandering attention.
MOL on SRB's latest attack at BA: "It's like a little Chihuahua barking at a dying Labrador. Nobody cares."
GDB From United Kingdom, joined May 2001, 11242 posts, RR: 82 Reply 18, posted (1 year 10 months 4 weeks 6 hours ago) and read 5676 times:
Thanks for an excellent piece on the Trident, as well as some other knowledgeable posts.
I think one reason for some UK airliners taking longer from first flight to service, (accepting in the Trident's case, the then revolutionary auto-land system), was that the companies were minnows, in capitalisation as well as in areas like facilities etc, compared to the US giants.
In those not so open market days, is was not unusual to see designs conceived with one major customer in mind, UA requirements helped drive the 727 for example, but in the case of US aircraft, these markets were much larger and these customers had specific requirements that were less eccentric than BEA and BOAC often were.
But, the Trident was fast, innovative, a boon to BEA in bad weather, had the original sized HS.121 been built, I think the 727 would still have greatly outsold it, what with Boeing's size, economies of scale, being part of the emerging 7-7 family, even so, we might still have seen maybe several hundred Tridents built.
In my early years at BA, I well remember seeing Tridents being scrapped at LHR, that were usually no more than 15 years old, many rather less, but it was going to be too loud soon for LHR, was a one of a kind not part of a family.
Still, it was both fascinating and sad to spend some time going through semi dismembered aircraft.
NEMA From United Kingdom, joined Feb 2006, 548 posts, RR: 0 Reply 19, posted (1 year 10 months 4 weeks 6 hours ago) and read 5652 times:
Great post to remember this fine bird and, surprised that WINGS didnt take up your offer to cover this at some point.
As it happens i pass a Trident every Weds morning, G-AWZJ ,well the front section of it anyway, this is as i pass by the gates of the Dumfries and Galloway Aviation Museum.
OldAeroGuy From United States of America, joined Dec 2004, 2848 posts, RR: 61 Reply 20, posted (1 year 10 months 3 weeks 6 days 23 hours ago) and read 5523 times:
Quoting BCAL (Thread starter): They went on to provide a reliable service with CAAC and a number were transferred to the air force and took up military service.
I believe Mao's rival, Lin Biao, died in a Trident crash while trying to escape.
Quoting BCAL (Thread starter): As will be seen, no accidents in the commercial life of Trident can be attributed to the design and/or malfunction of the aircraft.
The ability to retract the leading edge droop without retracting the trailing edge flaps was a serious design flaw and it was a primary contributor to the third accident you listed.
This deficiency was corrected as noted below.
Quoting TristarSteve (Reply 14): The original design had two levers, one for flaps, and one for droop. After the Staines accident the levers were connected by baulks so that the droop could not be retracted before the flaps.
[Edited 2008-03-18 19:44:41]
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
BCAL From United Kingdom, joined Jun 2004, 3384 posts, RR: 25 Reply 21, posted (1 year 10 months 3 weeks 6 days 19 hours ago) and read 5474 times:
Quoting GDB (Reply 18): I think one reason for some UK airliners taking longer from first flight to service
Other possible reasons for the long time from first flight to revenue service could be the lessons learnt from Comet, and interference by the UK Government (remember in those days the civil servants were running the main UK airlines, airports and everything to do with civil aviation).
Quoting OldAeroGuy (Reply 20): The ability to retract the leading edge droop without retracting the trailing edge flaps was a serious design flaw and it was a primary contributor to the third accident you listed.
This flaw was rectified after the Staines accident (June 18, 1972) and the CAAC accident occurred on August 8, 1988.
MOL on SRB's latest attack at BA: "It's like a little Chihuahua barking at a dying Labrador. Nobody cares."
BCAL From United Kingdom, joined Jun 2004, 3384 posts, RR: 25 Reply 22, posted (1 year 10 months 3 weeks 6 days 15 hours ago) and read 5397 times:
Quoting OldAeroGuy (Reply 20): I believe Mao's rival, Lin Biao, died in a Trident crash while trying to escape
That seems to be the case, although there is a dispute whether the crash was due to the aircraft running out of fuel, or pilot error
Quote: Supposedly after the discovery of the planned coup, Lin and his family (his wife Ye Qun and his son) and several personal aides attempted to flee to the Soviet Union. It is said they were chased to the airport by armed PLA officers and guards. According to the PRC account of Lin's death, their prearranged Hawker Siddeley Trident plane did not take aboard enough fuel before taking off, and as a result, the plane crashed near Öndörkhaan in Mongolia on September 13, 1971 after running out of fuel, and all on board were killed. Interestingly, the official Mongolian report on the crash investigation points out that the plane had plenty of fuel at the time of the crash. The investigators concluded that the plane crashed because of pilot error. The corpses were buried in a grave not far from the site of the crash. However, the Soviets reportedly sent a KGB investigative team, which recovered some of the remains for subsequent identification.
Source: Wikipedia
I should have included this in Accidents above.
MOL on SRB's latest attack at BA: "It's like a little Chihuahua barking at a dying Labrador. Nobody cares."
MEA-707 From Netherlands, joined Nov 1999, 3462 posts, RR: 45 Reply 23, posted (1 year 10 months 3 weeks 6 days 14 hours ago) and read 5359 times:
Quoting BCAL (Reply 22): I should have included this in Accidents above
There have been more big CAAC accidents, see http://aviation-safety.net/database/dblist.php?Type=280
This list makes the overall Trident safety figures a bit gloomy, but don't forget CAAC had a bad safety record til the late 1980s.
nobody has ever died from hard work, but why take the risk?
OldAeroGuy From United States of America, joined Dec 2004, 2848 posts, RR: 61 Reply 24, posted (1 year 10 months 3 weeks 6 days 9 hours ago) and read 5228 times:
Quoting BCAL (Reply 21): This flaw was rectified after the Staines accident (June 18, 1972) and the CAAC accident occurred on August 8, 1988.
I didn' imply that these two accidents were linked.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
25 NWOrientDC10: Here are some photos from the search index: I was able to find another photo but couldn't contact the owner for permission to show it so I will post
26 Qantas767: I would have thought that they would increase the ROD rather thatn decrease it...
27 ClassicLover: Don't forget this site either - http://www.zulukilo.org.uk/ I'm planning to visit this Trident when I got Manchester in July for the MAN meet. Can't w
28 Viscount724: I can't recall the Trident as being significantly different from a passenger point of view than the 727 for example. Some (not sure if all) BEA Tride
29 Dc863: I flew on several BEA Tridents to Belgrade when I was little. My last Trident flight was in July '81. I do remember one BEA flight where the cockpit d
30 BCAL: Both photos in the search index are reconstructed cabin interiors, the photo on the left being inside the Trident G-ARPH at RAF Museum, Cosford (Engl
32 Shankly: Excellent post which triggered some very happy memories of many hours spent out on the terraces of the Queens Building, in all weathers, as a young la
33 Bellerophon: Dc863 ...Which came at a point when the speed had deteriorated 25 kts since rotation... Not correct. If you actually meant that the speed had deterior
34 Mauiman31: Thanks. Fond memories of the Trident. Summer of 71' on first trip to Europe - BEA Trident - Frankfurt to Tempelhof and back. I was a naive kid and rem
35 Cs03: My flight log shows: July 1, 1979 British Airways LHR/ARN Trident three and July 23,1979 British Airways SVO/LHR Trident two This flight was after thr
36 BCAL: Indeed. Fatigue cracks were detected during the routine maintenance of Trident 3 G-AWZL in August 1977. BA's entire Trident 2 and 3 fleets were progr
37 Dc863: I remember staying at the Excelsior Hotel next to Heathrow with my father and having the window of our room open so I could hear the planes land/takeo
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