Why air cover means getting down to earth

WHEN John Major said on 10 July that Britain would be prepared to provide 'air cover' over corridors to beleaguered Sarajevo he exasperated air-power experts and opened unlimited possibilities for controversy and misunderstanding.

'Air cover' is not a precise technical term but most airmen interpret it to mean keeping enemy air forces off your back - not attacking enemy troops on the ground, which is close air support.

Since the former Yugoslav air force is flying very few sorties, and would not be much of a threat to any Western intervention force, that is not really the problem, anyway. 'There is really no air threat,' said an RAF officer yesterday. The problem is posed by intermixed and indistinguishable forces on the ground, who will kill with mortars, machine-guns, bayonets - and bare hands. Air power employed spectacularly and precisely might overawe and break them. But it is a high-risk strategy and means taking sides.

With reports of concentration camps in Bosnia run by Serbs and attacks on funerals by small parties manning mortars, how feasible is it to rely on air power alone to take out Serbian heavy weapons - mortars and artillery ranged on the hills, leading to the high peaks up to 20km (13 miles) south of Sarajevo?

Not very. RAF sources yesterday firmly denied speculation that Britain was planning to get involved. But this is a European problem in which the United States is reluctant to take the lead, and many believe Britain ought to be at the front of any intervention.

'As far as I can judge there are no plans,' said one senior RAF officer. 'We can take out the JNA (Yugoslav National Army - the armed forces remaining available to Serbia) on some grand scale,' he added, but political commitment is unlikely.

'Air cover' implies secure bases close enough to the scene of action to respond in time. Because there would be no ground-based radar and the occasional enemy aircraft could sneak in between the mountain peaks, airborne early-warning aircraft would be essential to control an operation.

So 'air cover' is the only politically acceptable solution, but will not do the job. It needs large forces on the ground. 'Nobody wants to,' Col Andrew Duncan, of the International Institute for Strategic Studies, said yesterday. 'But a lot of people realise that if you want to stub it out that is the only way you can do it.'

There are three options for a strategy confined to the air. You can only attack the artillery and mortar batteries which you have noticed firing. You can attack heavy military equipment on the Bosnian side of the border, which you know is not held by the Bosnians and Croatians. Or, finally, having given warnings to Serbia, you can attack military targets in Serbia. The first is not considered practicable, the third is still politically unacceptable, and the second two mean taking sides.

But to secure 'safe havens' or 'sanitised areas' for the Bosnian Muslims, you need to get them into the areas and then defend them against Serbs. This means occupying ground - and you cannot do that with aircraft. The target area for the attacking Serbs is Sarajevo - say 5km from the centre. Adding another 20km around that for artillery range gives a 25km radius circle - an area which would engulf Greater London. With a circumference of 150km and one soldier every 10m, and allowing men to sleep, that requires at least 15,000 troops - a division - awake, or two divisions in all.

Staff tables recommend 10 ton of food, fuel and ammunition per 1,000 men per day, assuming light ammunition usage. Hercules transport planes flying from nearby countries could carry 10 tons each, so you would need 30 planes a day landing at Sarajevo's 2,500m landing strip to supply those two divisions alone. But what about supplying Sarajevo's population - ten times the number? You could supply the two divisions alone by air - but not the people they were there to protect. That would require a land corridor from the port of Split - and probably another division to protect it.

It can be done. But will it?