Analysis: It was, sadly, only a matter of time before British troops locked in close-quarters battle with the Taliban became the victims of a so-called �friendly fire� incident involving a Nato airstrike.

Analysis

IT was, sadly, only a matter of time before British troops locked in close-quarters battle with the Taliban became the victims of a so-called "friendly fire" incident involving a Nato airstrike.

The UK military prefers to call such a tragedy a "blue on blue", based on the fact that there is nothing remotely friendly about having men killed by allies or by your own air force.

Even with global positioning equipment, there is always a large element of risk for any ground force calling in jets to bomb or strafe an opponent who may be firing from positions very close to its own soldiers.

In ideal conditions, there would be a 300 to 400 yard safety zone between friendly forces and the Taliban. The blast and shrapnel from a typical 1000lb bomb can inflict lethal damage out to more than 250 yards from its point of detonation.

But in the heat of an ambush, the niceties tend to be disregarded. Soldiers pinned down by a tactically skilful foe such as the Afghan insurgents often have no choice but to summon up any close-support aircraft available and instruct them to drop their weapons on the source of that hostile fire, however near at hand.

Nato pilots from the US, the RAF, France, the Netherlands and Canada operating the flying "cab rank" of strike missions over Afghanistan are under strict orders to clearly identify their targets before releasing bombs.

This is done either visually - frequently difficult with smoke obscuring the battlefield - or by sticking to map references supplied by those under fire below.

Mistakes happen most often when the ground troops or the pilots punch in the wrong targeting grid points in the heat of battle or the bombs themselves malfunction and explode away from the intended aiming mark.

In Iraq, where US aircraft and Patriot missile batteries have killed 12 UK servicemen in the two Gulf conflicts since 1991, the main problems were lack of thorough training by US pilots in the identification of an allied nation's vehicles and aircraft and over-enthusiasm in achieving kills. Fast-moving mobile warfare is another factor, where units might advance beyond known friendly zones and be mistakenly targeted as enemy forces by fighter-bombers.

While British forces have been critical of "gung-ho" US attitudes in the past, there has been praise for the close air support provided by flights of US F15 , A10 and B1 bombers in Helmand province in the past year.

A single, well-placed bomb can break the will of insurgents to press home an attack, even when they hold the best ground and outnumber the troops they are attacking. Britain has just six overworked Harrier jump-jets at Kandahar to support its 6000 soldiers. The battlegroups fighting daily battles in the Sangin valley and around the strategic Kajaki dam have to depend on other Nato airforces for most of their "flying artillery" back-up.

The latest tragedy, will reignite the festering row over America's embarrassing propensity to kill its own and other allied soldiers in devastating airstrikes.

In February, Britain demanded all information about a British soldier killed by US "friendly" fire should be released after an alleged cockpit recording of an American pilot opening fire on UK forces in Iraq was leaked. The tape exposed a catalogue of blunders which led to the death of Lance Corporal Matty Hull.

In Iraq, a total of eight UK service personnel have been killed in incidents of "friendly fire" since the start of the war, according to the Ministry of Defence.

The first "friendly fire" incident of the conflict came when a US Patriot missile shot down an RAF Tornado killing two airmen, Flight Lt Kevin Main and Flight Lt Dave Williams, in March 2003. Three days later two British soldiers - Corporal Stephen Allbutt and Trooper David Clarke - were killed west of Basra when their Challenger tank was mistakenly fired upon by comrades in another tank.

The latest tragedy also follows reports that British frontline commanders in Afghanistan want US special forces commandos barred from Helmand because they say the Americans' aggressive approach is undermining the UK's hearts-and minds campaign in the province.