Inquiry opens on helicopter disaster: Friendly-fire deaths underline risk of over-reliance on technology, writes Patrick Cockburn in Washington

ON 14 FEBRUARY General Ali Osman, the Kurdish commander for the region around the mountain town of Akra in Kurdistan, started an inspection tour of villages in the direction of the Turkish border. He took with him a video cameraman to shoot film of his visit to be shown on local Kurdish television.

As the Kurds neared the village of Dinarte, one of the few left standing by Iraqi army scorched-earth campaigns, they saw two helicopters passing overhead. Recognising them as probably belonging to the allied mission known as the Military Command Centre based in Zakho, the cameraman started filming. As he did so two fixed-wing aircraft appeared and shot the helicopters down in flames.

Only hours later did the Pentagon announce that two of its F-15C Eagle fighters, policing the skies of northern Kurdistan, had misidentified two US Blackhawk helicopters and shot them down, killing all 26 on board. The video was handed over to an allied inquiry which has still to report on what went wrong.

The loss of the helicopters underlined the dangers of high-speed fighters visually identifying targets. It did so at a politically sensitive time because it showed how difficult it would be for Nato to identify and destroy Bosnian Serb tanks and artillery pieces in the mountains around Gorazde and other Bosnian Muslim enclaves. And it dented the reputation of the US air force for technological efficiency which soared during the Gulf war.

It may also have reopened an old conflict within the Pentagon about reliance on technology. This originally revolved around the development of air- to-air missiles, such as the Sparrow and Amraam, which were fired from beyond visual range. Critics of the missiles said they were dangerous because the Identifcation Friend or Foe (IFF) equipment would always be unreliable.

In theory this should enable US planes to identify friendly aircraft. It is also famously unreliable and much disliked by pilots. Not only does it sometimes not work, but pilots do not know if it is not working. Proponents of the long-range missiles said, however, that this did not matter because Awacs control and reconnaissance aircraft circling overhead would be able to tell friendly from hostile aircraft.

Why did the whole system fail over Dinarte ? The F-15 pilots visually identified the helicopters as Iraqi. The Blackhawks have large stars and stripes painted on their fuselages, but the insignia are difficult to see at speed from the cockpit of an F-15. The helicopters, particularly when using external fuel tanks, do look like the Soviet-made Hinds used by the Iraqi air force.

Flying low over the steep Kurdish mountains the helicopters and the Awacs appear to have lost contact with each other. The IFF was not working. But over-reliance on technology had the effect that Pentagon critics said it would. It should have occurred to the pilots that it was unlikely that Iraqi helicopters could have strayed so far north of the 32nd parallel - which marks the start of the allied no-fly zone imposed at the end of the Kurdish rebellion in 1991 - without anybody noticing. Instead they convinced themselves they were facing Iraqi helicopters.

General John Shalikashvili said the US had made 31,000 flights over Kurdistan since 1991 without mishap. Mistakes happen. But the misdirected attack underlined that aerial identification and successful attack is more difficult than the air force admits.

In Vietnam, the failure of massed US air power to hit its targets became infamous. During the Gulf war, television viewers across the world saw video film of 'smart' bombs and Tomahawk missiles hitting Iraqi installations with pinpoint accuracy. There was no doubt that the air force's ability to hit highly visible immobile targets had increased immeasurably.

Against mobile or camouflaged targets, however, the air force's record was much less impressive. According to an official report on the air war during the first three weeks of attacks 'approximately half of the attack sorties into Iraq had been diverted to other targets or cancelled because of weather-related problems'. The Iraqi air force made little attempt to fight, but identifying targets on the ground proved difficult. Some 90 Iraqi Scud ground-to-ground missile launchers were claimed as destroyed by pilots. Subsequent analysis revealed that they had hit none.

The striking parallel between the exaggerated claims and the shooting down of the Blackhawks in Kurdistan last week is the self-confidence of pilots in the Gulf war that they were identifying and destroying the right targets. Many were disbelieving after the conflict to be told that they had hit civilian trucks or decoys. When it came to identifying an enemy they - and perhaps the US air force as a whole - had come to believe their own propaganda.