The 11 September catastrophe has cast a cloud over what would have been the safest year ever

The 11 September terrorist attacks have thrown into doubt whether conventional travel industry security systems - and not just in aviation - could ever be proof against a determined, extensive underground organisation on a worldwide basis.

Although the attacks on the USA were a huge leap in scale, they had many precedents, so the intelligence agencies and the industry cannot claim that there was no warning. Regular hostile acts have been perpetrated against states, using their national flag airlines as targets, since the mid-1960s.

Meanwhile, in 2001, the world's airlines have seen spectacular success in coping with the threats that they do understand as their own traditional area of expertise - implementing operational and technical measures to reduce accidents. Fatal accidents are at an all-time low (see chart), and the number of fatalities is one of the lowest ever. But the industry knows it cannot celebrate this latest proof of a now-established trend while the public perception of air travel safety as a whole has been so severely damaged.

In 1986, 25 passengers were killed in separate hijacks on two US aircraft, but there were five other such acts the same year perpetrated against airlines from other countries. With hindsight it is clear that, apart from the still state-owned El Al developing its own highly specialised security system, airlines and regulatory authorities in other countries did little to organise, and particularly to coordinate internationally, an appropriate security system.

In the mid-1960s the Popular Front for the Liberation of Palestine (PFLP) began to make hijacking a political weapon, having carried out four hijacks in the five years before the best-known event in Jordan in 1970. A Trans World Airlines (TWA) Boeing 707, a Swissair Douglas DC-8 and a British Overseas Airways Vickers VC-10 were hijacked to Dawson's Field, a disused, Palestinian-held airfield. There the passengers were used as hostages to bargain for the release of other activists, and the empty aircraft were blown up. In the early days, hijacking did not usually involve human casualties.

Sharpening up

The perpetrators in both the 1986 hijacks that involved US carriers were Middle East-based terrorists representing political factions rather than states. The airlines were the USA's two de facto international flag carriers at the time - TWA and Pan American World Airlines. A baggage-hold bomb exploded in the TWA Boeing 727, killing four passengers on the approach to Athens, Greece. In the other event, involving a Pan Am Boeing 747, 21 of the 383 people on board were killed by the terrorists on the ground at Karachi, Pakistan.

Two years later Pan Am flight 101 was brought down by a terrorist bomb over Lockerbie, Scotland, killing all 259 people on board. The USA, rather than the airline, was clearly the target. Europe was the place where the Lockerbie bomb was placed on board the aircraft by a Libyan, and after that incident the continent began to sharpen up its security act in a co-ordinated way. Lockerbie was the first time large numbers of people had died following a security failure. A bomb in checked-in hold luggage had gone undetected, and the bag had not been unloaded when the passenger failed to turn up for boarding.

But still, for several years after Lockerbie, except 1993, people were killed in acts of "illegal interference" with flights. The reason for hijackings, however, were changing, with political motivation becoming less frequent.

Politically motivated hijackers seemed to be giving aviation a break between 1994 and December 1999, when an Indian Airlines Airbus A300 was hijacked to Kandahar, Afghanistan. The hijackers, who had killed one passenger, demanded the release from an Indian prison of Kashmiri Islamic fundamentalist guerrillas. The Indians released three guerrillas, and the hijackers were given a car and told to leave. This complete success for the hijackers may have influenced subsequent thinking among people of that mindset.

There was still no coordinated international industry reaction to the threat, however, and no clear, standard international definition of whether provision of security was the duty of the state or of the industry, and this remains the case.

If it were not for 11 September, the year 2001 would be a cause for industry congratulation, with accident rates half what they were 10 years ago, and simple numbers, both of fatal accidents and of fatalities, continuing a downward trend. The annual average for the decade 1991-2000 showed 48 fatal accidents - including fatal accidents to commuter and freight operations - and 1,126 fatalities. Last year saw only 33 fatal accidents and 778 fatalities.

Falling accident rate

The International Civil Aviation Organisation plot of the number of fatal accidents per million flights for large passenger aircraft operations shows the fatal accident rate reducing consistently to about half what it was 10 years ago. In 1991 there were 1.7 fatal accidents per million flights, and in 1999 the rate dropped below 1 fatal accident per million flights for the first time. This reduced again to 0.85 fatal accidents per million flights in 2000. The projection for 2001 looks promising despite the fact that the overall number of flights has probably fallen slightly because of the recession and the effects of 11 September.

There seems to be only one 2001 accident in which the investigation might bring new knowledge to the industry, either in the fields of materials technology or of operating techniques: the 12 November American Airlines Airbus A300-600 accident in New York (see accident lists). In the sequence of events leading to the crash the composite tail fin separated, and inquiry will attempt to find out whether the causes involve structural materials or design, a rudder control system anomaly, or crew control input - or all of these things.

An issue raised by the 24 November Crossair Avro RJ100 accident on approach to Zurich airport is whether environmental requirements should have as much power as they do over the mode of aircraft operation when approaching and departing from airports. This crew, for environmental reasons, was told to use a runway with a non-precision approach aid on a snowy night when the crew had briefed for an approach to one of the instrument landing system runways. The aircraft crashed on approach, making this arguably the first fatal accident in which environmental procedures might be judged to be a causal factor.

The 4 October crash of a Sibir airlines Tupolev Tu-154 was grudgingly admitted by the Ukrainian military to have been caused by accidental shoot-down by one of its missiles that went astray during an exercise. That might have become another of the aviation mysteries if it had not been for the fact that the area is under such intense military radar and airborne surveillance by several countries.

But the industry knows what 2001 will be remembered for. In the four aircraft used in the 11 September suicide hijacks, 351 people died and so did an estimated 3,000 people on the ground. Just as Lockerbie alerted some countries to the need for security, 11 September has woken the world up to the need for global co-operation to defeat those who would use commercial air transport as a political weapon.

Source: Flight International