THE AIRLINE-ACCIDENT statistics for 1996 (P31) suggest that there is a serious safety problem in the air-freight market. Over one-third of all fatal airliner accidents last year were to non-passenger aircraft: they caused the deaths of 158 aircrew and other occupants, and more than 350 further deaths of innocent third parties on the ground.

At the same time as these statistics were being compiled, the US Federal Aviation Administration was readying an airworthiness directive which calls for checks to - and possible grounding for reworking of -many freight-converted jet airliners. The FAA's complaint is that many of these aircraft have been converted using invalid structural calculations: the Administration's fear is that as a result many of them are too weak to be safe.

Such fears strike at a sector of the industry which - despite the apparent boom in air-cargo traffic - may be the least-prepared and least-resourced to cope with them. Comparatively few air-cargo operators are able to buy new, dedicated, cargo aircraft: most of them (even, in part, high-profile ones like FedEx) still buy and convert older airliners which no longer pass the passenger-acceptability and operating-economics tests for the front-line airlines.

Because of the low yields on cargo (and the generally low utilisation rates of the aircraft in this business), freight companies tend to not be the biggest payers in the business. Could it be that their crews are either older (retired from front-line duties with the big airlines, but still capable of doing many years of useful flying) or younger (those who have not - or not yet - made the grade) than those of the big airlines? Could it be that while many of these pilots have undoubted skills and experience, they do not get the same training quality as their counterparts in the mainstream passenger airlines? Or is the problem a psychological one: aircrew fly particularly smoothly and carefully when passengers are on board to keep their custom. Pallets or containers do not judge the pilots. Whatever the truth, it needs to be known.

There seems to be little evidence yet that the FAA's fears about the standards of conversion in the jet-freighter sector can be directly translated into the disproportionately high accident rate there. Most of the 1996 freight-aircraft accidents which can be ascribed to technical problems centred on engine failures or fires. Far more seem to be attributable to failings in the cockpit than in the aircraft structure.

The UK Civil Aviation Authority has recently determined that, globally, freighters have a "far higher" accident rate than passenger airliners, and its new Accidents Analysis unit is to examine the evidence to try to uncover common factors.

A significant problem in the freight market (as with airline safety as a whole) seems to centre on the developing world, with a particular problem in the use of aircraft from the former Soviet Union in those markets. Again, it seems not to be an issue just of the aircraft themselves, but of the way they are operated.

It is axiomatic among aircrew that, if you like a life of long duty-hours and night-operations, flying freighters is for you. This is as true of Beech 90- and Cessna Caravan-type overnight parcels-delivery as it is of large cargo-jet operations which, reasonably enough, tend to use busy airports when they are least busy - late at night.

Until recently, accident investigators have been hesitant to ascribe crew fatigue as a primary or even contributory cause of accidents. Significantly, the only two airline accidents where aircrew fatigue has been described either as the cause, or one of the primary causes, have been to freighters: the American International Airways DC-8-60F crash at Guantanamo Bay, Cuba, in August 1993, and the December 1994 Air Algerie Boeing 737-200F accident on approach to Coventry Baginton Airport, UK. Luckily, in neither of these cases were there third-party fatalities (although it was a close-run thing at Coventry ), but in both accidents the aircrew displayed the kind of reckless "get-home-it is" which is one effect of fatigue.

Nonetheless, freighter accidents are killing more and more third parties, (and a frighteningly higher number of "crew" than could ever legitimately be needed to operate these aircraft). On those grounds alone, action is needed now - and not just in the USA and UK.

Source: Flight International