David Learmount/LONDON
FIGURES FOR 1995 confirm that numbers for world airline fatal accidents are showing an upward trend. The 1995 fatal-accident total (57) and the number of resulting fatalities (1,215) are significantly above the annual averages for the decade (respectively, 44 and 1,084). This move occurs, despite the industry's long-professed objective to reduce accident rates fast enough, to ensure that crash numbers do not grow as travel increases.
The year started well. After the first six months (discounting hostile acts), there had been only 155 fatalities in 23 fatal accidents, ten of which were to small aircraft on cargo flights. If these figures had continued, it would have been an all-time safety record. They did not. The number of fatalities increased by a factor of eight and fatal-accident numbers almost trebled. December was particularly disastrous, with four of the years nine scheduled passenger jet-airliner crashes, killing 386 people. The world also witnessed its worst-ever turboprop airliner crash, when a Trans Service Airlift Lockheed Electra plunged to the ground, killing 141 passengers, soon after take-off in Lunda Norte, Angola.
Controlled-flight-into-terrain (CFIT) numbers also climbed significantly in 1995, to equal those of 1992, which was recognised as being a particularly bad year. CFIT has for many years, been the cause of the greatest number of commercial air-transport fatalities and in 1995 caused more accidents (21) than any other causal category, except the catch-all group, described as "aircrew error". CFIT, like other categories of accident, almost always includes some form of aircrew error as a component in the chain of events leading to disaster.
CFIT INCREASE
A CFIT increase is a disappointment to those in the industry, and it comes despite a determined effort by the Flight Safety Foundation (FSF) and the International Civil Aviation Organisation (ICAO) to reduce CFIT accidents. In 1990, the FSF (among other measures) combined with companies from all sectors of the air-transport industry to start a campaign of education with this intention. The FSF also offers a CFIT checklist to all airlines, which wish to survey their own operations for potential weaknesses, and ICAO is tightening regulations about the carriage of ground-proximity warning systems. The campaign is not yet having the desired effect, possibly because so much of the programme depends upon industry willingness to admit that even carriers with a good safety record are not immune to the errors, which lead to CFIT.
Perhaps because it illustrates this point so dramatically, the biggest shock of 1995 was the American Airlines Boeing 757 CFIT crash in December near Cali, Colombia. This involved an airline with one of the best safety records in the world and an aircraft type, which, in its 13-year operational history, had not suffered a fatal accident before. Yet the initial reports of the Colombian Civil Aviation Authority and the US National Transportation Safety Board, based on readouts from the 757's cockpit-voice recorder (CVR) and flight-data recorder, have stated categorically that the crew failed to carry out pre-descent briefings or checks. This would be a breach of standard operating procedures under any circumstances, but, when operating at night into an airport surrounded by mountains, the omission seems extraordinary to line pilots.
As with so many accidents, the chain of events leading to the Cali crash was started by an apparently innocuous happening. The crew, were expecting a particular approach procedure on to the northbound runway (01), with which they were familiar, because it is the main runway and the only one with an instrument-landing system for the final approach. Because the wind at Cali was calm and the American flight was approaching from the north, Cali air-traffic control (ATC) offered the crew the option of carrying out the VHF omni-range/distance measuring equipment let-down to reciprocal runway 19, using a specified arrival procedure.
The crew accepted the proposed arrival, and then set about looking for the appropriate charts while still descending with airbrakes extended. From the limited CVR transcripts published by the Colombian CAA, it would appear that the crew were not familiar with the approach they had accepted and did not have the charts to hand, yet they continued their descent with disastrous results (Flight International, 10-16 January, P8). If the crew had not been offered the alternative approach, the accident would not have happened, but there is no suggestion from the official information so far released that ATC could be criticised for offering the choice.
During the investigation, it will become apparent whether the much-discussed human-factors effects of having ultra-smart flight-management systems (FMS) and clear lateral navigation displays (NDs) will be shown up in the clear relief which only disaster seems to bring. The crew, were certainly relying on their ND, through use of their FMS, to provide them with the answers they sought when confused by the new let-down procedure offered by ATC. Meanwhile, the FMS was entrusted with the aircraft's flight-path and, "obedient but dumb", as one US pilot commentator remarked, turned the aircraft toward a beacon which the pilots believed was still ahead of them, but which, in fact, they had passed. That turn initially took the aircraft eastward toward the mountains and the pilots acquiesced for 90s, according to the interim report, before they decided to take charge of the aircraft's heading themselves. It was too late.
Modern-screen NDs have the potential to provide better situational awareness for crews than the instruments they replace and, combined with the accurate flight-paths and performance prediction, which FMS can provide, are definite safety benefits. The US Federal Aviation Administration, together with other agencies, is continuing to study the overall effects of "glass cockpits" on aircrew performance. The Cali incident will give the inquiry some food for thought.
The fact that the American crew had, however, begun their descent without the appropriate checks and procedures, has clearly been a factor in FAA Administrator David Hinson's statement that American's training procedures are to be investigated. Another quoted factor had been the accident at Bradley International Airport, Connecticut, USA, where an American Airlines McDonnell Douglas MD-83 escaped disaster by a hairsbreadth when it flew much too low on the approach. The aircraft hit trees on a ridge, the engines lost power as they ingested debris, and the pilot managed just to get the aircraft into the airfield. No one was hurt.
The FSF says that the moral of the story is that it does not matter how good an airline's safety record is, CFIT can still happen unless constant awareness of its multiple causes is a specific part of the training programme's aim.
NOTHING CHANGES
Old truths, and the belief by some that nothing changes, seem to have been confirmed by events in 1995. The resistance of CFIT to intelligent attack by the industry was only one case in point.
Once again, Africa and South/Central America performed consistently the least well of all the world's regions. In absolute figures, South/ Central America and the Caribbean (13 fatal accidents) topped the accident league, Africa came third (nine) and the CIS (eight) fourth. North America came second (12), but, considering the fact that the latter carries out about half of all the world's commercial air-transport activity, its rates remain relatively far better. Also, the fatal accidents to African airlines consisted of three involving scheduled passenger jets, and four to chartered operations within the continent - including the disastrous Electra crash. In North America, apart from the Cali accident, the majority of the accidents were, less harmfully, to small cargo operators.
Boeing's chief of systems engineering, Earl Weener, speaking at the FSF's annual airline safety seminar in November 1995, provided figures proving conclusively that, using hull-loss accidents as a basis, the disparity in safety standards between the world's safest regions and those consistently less safe is not only large, but increasing (Flight International, 22-28 November 1995, P22). The year's figures have not suggested that any change is on the way.
Weener also points out that in-production aircraft have better safety records than those of their forbears, but, again, the countries which already have relatively high safety standards better exploit new technology's ability to provide safety improvement than those nations whose standards are relatively low.
It is in these issues that the problem for an industry trying - and failing - to improve world average safety lies. Airlines, which are already safe, can expend a great deal of effort, but there is room to improve their safety figures only slightly. The allocation of resources where there is room for major improvement will provide the elusive answer to the accident rate reduction the industry wants to see. Meanwhile, Cali reminds the top performers that no one is perfect.
Source: Flight International
