Private pilots all over Europe must be whooping with joy.

The European Union Transport Commissioner has decreed that the time has come to limit Europe's military demands on the Union's airspace.

Loyola de Palacio has told European airlines: "the exclusion for military purposes of huge parts of the European sky is, in my view, due to old-fashioned reasons dating back to the days of the Cold War. This has to change."

Military planes do not just fly in conflict

Many within and outside the aviation world will agree with her.

They will be overjoyed to hear that she plans to push for what she calls "one single sky" to accompany the single market and the single currency.

But while Europe's light aircraft, private helicopter, glider, micro-light, hang-gliding and paragliding population will be chuffed, there is a more serious and pressing need for freeing up airspace: Europe is running out of it.

Gripping a jelly

Airline traffic badly needs the space allocated to military use.

Congestion around airports is reaching alarming levels. This has been the worst year on record for air delays. Air traffic is forecast to grow at 6% a year, so the prospects for relief are not good.

Unless Europe can gain more civil air.

Which is what the charmingly-named commissioner is offering - but the means may be far tougher to accomplish than the delivery of the message.

Trying to put a figure on the amount of sky over Europe which is limited for military use is like trying to grip jelly - when you think you've got it all, a piece squeezes out somewhere else.

Senior RAF sources reckon "about 5%". Aviation and defence industry analysts say "about 20%".

Lufthansa complaints

It's all very opaque because much of the designated military airspace changes all the time.

Military air corridors are opened or closed at short notice, others are used only temporarily (for training or exercises, say) and may be available for civilian use most of the time, and so on.

Eurocontrol is the Brussels-based air traffic management centre that is supposed to know about these things.

But the transparency which has become so fashionable everywhere else in our world eludes this centre so far, and it refuses to put a number on what the military needs and how much of our skies is civilian airspace.

One thing all agree on - Europe has more military airspace than anywhere else. This is partly historic, a legacy of Europe's past conflicts and the Cold War.

But there is a capital cost to too much military airspace, and the airlines are paying it.

Not only do they need the space as civilian space becomes crowded, it can also be expensive for them in time, money and fuel costs to divert, up, over and around military corridors.

Indeed none will be happier to see a solution than Lufthansa.

It has claimed that its profits have been seriously affected by changes that it had to make during this year's NATO action to relieve Kosovo.