So called 'friendly fire' incidents cost five British lives in the Iraq war. An MPs' committee is pushing the Ministry of Defence to step up efforts to minimise such deaths in future conflicts.



But there's a new factor that could possibly make a difference to a pilots judgement.



In the LAST Gulf war more than half of all American pilots used amphetamines to keep them going on long missions. And they did the same in the latest war in Iraq. What's more, the US Air Force says the drug they use - Dexedrine - isn't harmful. They need it, they stay, to stay awake and alert.



But with amphetamines now being linked to a friendly fire incident in Afghanistan, how safe IS its use among pilots?



The US Air Force was a decisive factor in the victory in Iraq, delivering "shock and awe". But it wasn't just the Iraqi troops who were intimidated by US air power.



Trooper Chris Finney - Household Cavalry:



"I seen his face and all that, I noticed it was an American plane, but I didn't want to believe it was because it was friendly"



Trooper Finney experienced the force of US firepower first hand when his tank was attacked by a US A 10 "Warthog".



"When I saw the pilots face the second time he came round and I spotted it was an A10. There was just a sense of hopelessness but there was nothing I could do about it."



Trooper Finney was wounded, his friend Lance Corporal Hull was killed in the attack. Another so-called friendly fire death. In the recent conflict, a third of all British fatalities were killed by their own side. Correspondents in the field reported that British soldiers would sometimes run for cover as American planes flew overhead.



And revelations about a friendly fire incident in another recent war won't have made them feel any safer.



April 2002. Two American F-16s are flying a mission above Afghanistan. Believing themselves under attack, they go in for the kill.



They did in fact hit Canadian soldiers. Four died, eight were wounded. The US Air Force says the pilots behaved recklessly. The pilots say that their judgement may have been affected by the fact that they had taken amphetamines, amphetamines prescribed to them by the US Air Force.



In 'Top Gun', Hollywood's version of a fighter pilots life, Tom Cruise famously says he feels the need, the need for speed. Of course he wasn't talking about amphetamine but the fact is that amphetamine use by pilots is now routine US Air Force policy. According to its own documents amphetamines were handed out in their hundreds during the last Gulf war. 57% of pilots used amphetamines at some time, in some units amphetamine use was more than 96%.



Dexedrine is the drug the Air Force uses. It's given to keep pilots alert when their tired minds and bodies would prefer to sleep.



Colonel Peter Demitry - US Air Force spokesman:



"This is a safe and effective programme. The science is exhaustive and compelling. There's six decades of field usage all the way back from World War Two where the controlled minuscule use of Dexedrine under the direct supervision of a flight surgeon has been proven to be safe."



The US Air Force says the pills are only given when there's a real danger of fatigue - on long missions, or when pilots fly at night. All pilots are tested before Dexedrine is prescribed to make sure there are no adverse reactions and use is voluntary - the pilots themselves decide whether to take the drug or not. But it is not without side effects; the warning's there on the packet:



"Amphetamines may impair the ability to engage in potentially hazardous activities such as operating machinery or vehicles." And some experts believe its use may make accidents like friendly fire more likely.



Dr John Morgernstern - Columbia University:



" When you think about the potential for this medication to make people feel more jittery, to make people fell more vigilant and perhaps slightly more threatened. These pilots are making an instantaneous almost decision about a threat situation and how threatened they are. Again, I think we just don't know and certainly lit seems to me the possibility is there that it potentially could have had an important effect on their judgement".



And some Air Force pilots who've been tested with Dexedrine on the ground are also anxious.



Tom Heemstra - former US Air Force pilot:



"Some of my symptoms were a little euphoria and maybe giddiness or just you know a lot of energy and ready to do physical activity, that sort of thing, but then when you add a combat situation now you're adding a lot more stress that you know, you can't even really project what effects or the results could be from taking a drug."



The RAF - joint coalition partner - has strict rules on stimulants:



"RAF aircrew don't take amphetamines under any circumstances" a spokesperson told Channel 4 News. And in 1992 - after the first Gulf War - the US air Force also stopped using the drug, by the express order of it's then commanding officer.



General Merrill McPeak - former US Air Force chief of staff:



" John Wayne doesn't take speed when he goes across the beach at Iwo Jima and Jedi Knights aren't on go pills. I believe that there is a warrior ethos, there's an approach to the job of being a warrior and it seemed to me inconsistent with the approach I wanted to take to create a culture, a warrior identity, in which you have to take drugs in order to fight somebody. When I fight somebody I want the other guy to have to take drugs."



But when his watch was over, amphetamine use was re-introduced. The fact is that amphetamine is a key part of the US Air Force's strategy. In modern warfare combat aircraft fly ever-longer missions - circling for hours as they wait for the targets on the ground to be identified and flying missions from bases thousands of miles from the theatre of conflict.



Colonel Tom Hyde - US Air Force Pilot:



"..Since in many instances we don't have the opportunity to do a sleep cycle adjustment, because we do want to project power as soon as we possibly can, because we do want to put pressure on the enemy 24 hours a day, this is one of the tools we can use that allows us to do that."



During the recent conflict some British commanders would joke - away from the cameras - that they weren't expecting much opposition from the Iraqi's, it was the Americans they were worried about. Hardly a ringing endorsement of the world's premier fighting force. If the use of amphetamines is found to be a factor in friendly fire incidents then the US Air Force may have to reconsider its policy.