|By Charles Kennedy|
March 23, 2001
How BOAC Flew Five Comet Jet Airliners Into The Ground Without Injuring A Single Passenger
Britain’s de Havilland Comet 4 introduced jet travel to the North Atlantic on October 4th, 1958, fifteen days before the debut of Pan Am’s 707. The airline was the UK’s longhaul flag-carrier British Overseas Airways Corporation (merged in 1972 with British European Airways to create British Airways). The historic day followed the saga of the Comet 1, which had flown the world’s first jet services, launching a new era in aviation on May 2nd, 1952 throughout the British Empire to Africa, the Middle East, the Indian subcontinent and South East Asia. The Comet 1’s jet speed shrank the world to the size it is now, but de Havilland’s brave pioneering steps into new cutting-edge technology went unrewarded as the skin and structure of the Comet 1 proved to be lacking the structural strength necessary for high speed, high altitude flight, and the type was permanently grounded after two aircraft exploded in flight in 1954. The strengthened and stretched Comet 4 was never a commercial hit on the scale of the 707, but it was a pioneer and a solid seller, appearing in many liveries including Middle East Airlines, Mexicana, East African Airways, Olympic, Egyptair, Singapore Airlines (MSA), Sudan Airways, Aerolineas Argentinas, Kuwait Airways, AREA (Ecuador), Air Ceylon, and a number of British charter carriers including Channel Air and Dan-Air, who eventually flew 48 of the type and flew the last ever Comet service, on November 9th, 1980.Click for large version
CFIT stands for Controlled Flight Into Terrain, and has proved to be one of the most difficult causes of accidents to eliminate. No matter what safety devices and procedures are put in place, crews still fly perfectly serviceable aircraft into the ground from time to time. Glass cockpits with moving maps, and better crew co-ordination and Cockpit Resource Management (CRM) have all helped, but not managed to eradicate the problem completely, much to the despair of crash investigators and the airlines.
However, those who are horrified at the needless and apparently unstoppable (if occasional) loss of life and aircraft should cast their thoughts back to a time before glass cockpits and CRM, and specifically BOAC’s experience as they re-introduced the world to jets with the Comet 4, and in the process left trails of sparks across airfields at both Rome and at Stansted in the UK, a pair of tyre tracks across a game park in Kenya, stripped a few trees of their leaves on the outskirts of Rome, and reduced the elevation of a hill near Madrid by a foot or so. That not a life was lost in any of these incidents must represent the luckiest streak in the history of commercial aviation.
Comet 4 cockpit interior (the placarded flap limitation
speeds can be seen above the copilot s windows, implicated
in two belly-landings). Photo © Ian Moy
Early jet captains had started flying in many cases at the very dawn of aviation, and certainly during or immediately after World War One. BOAC crews mostly had experience of Imperial Airways, Handley Page HP42s, Croydon Airport, biplane airliners, flying boats, and bomber commands in World War Two. (There is the joke about the captain who got lost taxiing at Frankfurt-am-Main in the 50s: “Have you never been to Frankfurt before?” asked the controller as the flight asked for assistance in finding the ramp. “Yes I have. But we didn’t land.”) While pilots on jet transports today are systems managers, team managers and by-the-book precision operators, the pioneer days required a totally different, in fact totally opposite, set of skills. Operations in the earliest days of flying threw up wildly different scenarios on a daily basis which needed instant, instinctive individual rogue solutions. This translated into some enormous egos and a huge resistance to team work, especially when the team included such lesser forms of life as copilots – as a hilarious near-disaster on a Pan Am 707 flight to Beirut illustrated. The apartment buildings south of the city were flashing beneath the nose on short finals and the co-pilot couldn’t remain silent any longer as it became obvious that the configuration warning system was inoperative and the captain had forgotten the gear. “Captain, shouldn’t we lower the undercarriage?” The man in the left seat was appalled by the insubordination. “I will ask for the gear when I am good and ready!” A nano-second later: “Gear down!” Another manifestation of the indiscipline bred by aviation’s pioneer days was the willingness to abandon the checklist or published procedure at any opportunity, which brings us to our first BOAC accident, a gear-up landing at Rome which was the inevitable result of a dangerous speed reduction technique.
Unconventional descent procedures used by early jet crews to enter the circuit were known as Jet Penetration, and would now be impossible due to the volume of traffic and the need for complex manoeuvring patterns for traffic spacing at modern airfields. It was quite often the case that an incoming flight would be the only aircraft in the area and in the absence of any legal speed restrictions (ie 250 knots below 10,000 feet as is the case worldwide today) a descent could be flown at high speed and a high rate of descent. Some crews flew to a ‘Top Of Descent’ point much closer to the runway than would be the case today (60 miles instead of 100), pop the speedbrakes and drop like a stone with the engines at idle, all the way from 35,000 feet virtually to the touchdown point. In the Jet Penetration profile, the aircraft was usually flown down to 4,000 feet and finally slowed down by halting the descent and flying level until the airspeed reduced to the maximum speed allowable for the use of forty degrees of flap, 170 knots. The configuration alarm would be triggered by flaps forty without the gear, and cancelled just as quickly by a crew member. Some buffeting would result as the jet slowed further, and the gear would finally go down without reminder from the silenced cockpit systems, and a normal landing would ensue, albeit ten minutes earlier than if a conventional descent profile was employed. It was inevitable that a crew would sooner or later make an unintentional gear up belly landing and this was what resulted at Rome at the end of a flight from the Middle East.
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Two BOAC Comets at Düsseldorf in 1962.
Photo © Günter Grondstein
After plunging silently down from cruise altitude, the flaps were extended to forty and the alarm bell was silenced. The approach was flown in blissful ignorance of the fact that far from dangled, the Dunlops were still stowed in their wheel wells. If the aircraft seemed a little more sprightly than usual, it was probably dismissed: “Must be a light load tonight.” The belly landing and ground slide that followed was so gentle that everyone outside the cockpit continued to think the landing was completely normal and that the Comet had come down on it’s extended gear rather than its exposed underside. As the engines became silent a flight attendant opened a door, only to be stunned by the sight of a fireman standing outside on the grassy surface at the runway’s edge that was bizarrely only a few feet below the level of the door. No-one was hurt, but a verdict of Pilot Error was unavoidable even if rudimentary procedures and a lack of instrument cross-checking did lead the pilot into a trap that was lying in wait as long as the procedure was used. To further prove this point, an identical crash-landing occurred during a training mission at Stansted in the Essex countryside outside London a few months later.
Captain Peter Duffy, author of ‘Comets Concordes (And Those I Flew Before)’ (Paladwr Press 1999) unwittingly illustrates the lack of CRM and inability of junior airmen to question the judgement of those more senior when he writes of a flight into Khartoum, Sudan, where the BOAC check pilot in the left seat asked him to perform, under the check pilot’s instructions, such an approach. “I was a little doubtful about adopting this non-standard and unauthorised procedure, although it was within the permitted performance envelope; but curiosity prevailed, supported by a desire to avoid upsetting him by a refusal.” Captain Duffy describes his worry about having to cancel the configuration warning a couple of times during the procedure, and his fears that it could result in an accident were justified at Rome soon after his flight to Sudan.
The Comet 4’s spotless record (at least in terms of lives lost) continued unmarred by another pilot error which would have been instantly spotted if crew cross-checking had been performed. This incident, outside Nairobi, Kenya, should have been a major disaster had luck not played a major role as the aircraft came to earth nine miles short of the runway. The aircraft had flown a relatively conventional descent, albeit with the captain’s altimeter set to 938 millibars of barometric pressure instead of 839 millibars, making the instruments indicate an altitude 3,000 feet higher than the aircraft really was. The Comet 4 made a perfect touchdown on it’s extended gear in Kitengele game park, astonishingly in an area of hard flat grassland – surrounded on all sides by trees, rocks, crevices and ridges. The captain, having flown his brand new jet into the ground, was allowed a once-in-a-billion opportunity to simply apply full power, raise the nose and fly away. Descending in a jet until blindly hitting the ground in the countryside surrounding Nairobi must surely result in an instant and fiery demise, and the fact that these passengers and crew members lived to tell the tale is a deliverance rarely allowed in aviation.
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Two BOAC Comets shot at LHR in May 1960.
Photo © Clive Dyball
The crew in the next incident were not at fault, but it does illustrate something else that is much less of a problem in much of the world today – woefully inadequate ground aids. The venue was once again Rome, and the problem was a radio beacon near Ciampino Airport which shared the same frequency as a more powerful transmitter elsewhere in Southern Europe, enough to divert the indicated heading toward high ground. The problem had presumably resulted in dangerous proximity to terrain before, but never was a flight brought so close to disaster as this BOAC Comet one night in the early 60s when the erroneous heading was not caught in time and the only thing that saved the flight from a tragic end was the appearance in the aircraft’s landing lights of woods and ground rushing up to meet them. Full power was applied but the aircraft ploughed through the upper parts of the trees, the gear ripping a swathe through and the four Avon engines ingesting branches and leaves. Thrust from the engines was thankfully undiminished by the hail of debris, and the flight pulled clear, managing to climb away and make a safe landing. There was no actually damage sustained by the Comet 4 or it’s engines other than some twigs and leaves caught in the gear.
The Comet’s strength was demonstrated beyond doubt a few months later on a dark night as a BOAC flight from Africa approached Madrid for it’s final transit stop before London. The jet was making a non-precision visual approach which nearly ended 6 miles short of touchdown. The approach was not stabilised and the dangers of ‘black-hole’ approaches were not fully realised at the time – approaching a strip over unlit ground or water at night with no visual reference to judge one’s height above the ground. As the descent profile sagged slightly below the desired glideslope, a ridge loomed out of the darkness, too late for evasive action. The jet smashed onto the very summit of the ridge. On the underside of the engines were emergency cut-off switches, and the impact triggered the automatic shutdown of engines one and two. Shorn of it’s landing gear, aircraft slid for the briefest moment after impact before the ground fell away, launching the severely damaged plane back into space. Instant and correct action by the pilot held the direction of the flightpath, with power from engines three and four combined with full right rudder and aileron. The runway remained in sight throughout the entire sequence and the crew managed to belly land their crippled jet on the runway. There was no fire and all the passengers and crew aboard evacuated without any injury. Perhaps even more miraculous is that the aircraft was repaired and ferried back to London and after extensive work, returned to service by BOAC.
In fact some of these incidents have been repeated in modern times, as in the case of the British Airways 747-200 that came within 80 feet of smacking into the ground outside Nairobi in the 80s due to a misset altimeter, just as at Kitengele a couple of decades previously; or the American Airlines MD80 that hit a ridge on approach to Hartford CT in a series of circumstances identical to the Madrid near-disaster, complicated by an incorrect altimeter setting, pilot fatigue and windshear. As at Madrid, the ground fell away steeply enough from beneath the MD80 to allow the aircraft to continue in a more-or-less straight line with one engine on fire and return to earth with it’s gear still down on whatever happened to be ahead – which was luckily Bradley International Airport.
So perhaps we haven’t learnt everything that could be learned from the string of incidents that befell BOAC’s Comet 4 fleet. But it only took ten years for aviation to mature from there to the point that the introduction of a new type could be done achieved without risk – and the biggest step up in terms of the scale of operation in history was accomplished with the debut of the 747 in 1970 and the five accident-free years that followed. Things have changed even more for the better – all of the latest generation of widebodies have been safely flown for nearly a decade without a single major incident (the A330, A340, Il 96 and 777).
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Comet 4 ready to board at Tokyo Haneda, November 1961.
Photo © Mel Lawrence
As well as providing interesting anecdotes, close encounters with disaster bring to light failings in aircraft, procedures, ground aids, maintenance and pilots, thereby sparing the lives of not only the passengers and crew in the incident but also those who take to the air afterwards (indeed when a Comet 4 made an unintended belly-landing at Stansted the repair work revealed corrosion caused by Redux adhesive that would not have otherwise been discovered, and modifications were made to the worldwide fleet). It is only ignorant and alarmist individuals who claim that the skies are unsafe – mankind is now a winged species and has been for some time. In the wake of incidents and accidents such as those above we have learned how to do so with unprecedented confidence and safety.
Charles Kennedy is a professional musician who has recorded and toured with many big names as well as releasing three albums with his own band Night World between 1989 and 1992, and a solo album of instrumental music in 1996 under the name The Aries Project (despite being a Leo). Charles owns and runs Invisible Hands Music, an independent record label based in London
(est. 1994), releasing albums by Wishbone Ash, David Fisher, Rob Reynolds and a series of dance compilations. He is currently finishing a second Aries Project album and rehearsing for a tour. On an aviation front, he is currently editing broadcast-quality footage taken at Heathrow Airport into a short film for commercial release.