They fly daring missions in state-of-the-art #20m Tornados bearing high-tech smart bombs costing #22,000.

But in the event of being forced to eject from their jets, the RAF bomber pilots and navigators presently in action over Iraq may owe their lives to a simple handful of gold coins.

In the combat survival waistcoats worn by each airman for use if he is shot down are 10 solid gold Krugerrands, each worth around #180 at current prices, for bribing local people to help him reach safety.

Also in the waistcoat is a note in a dozen languages - including Arabic, Persian, Turkish and several local dialects - asking for assistance and promising further rewards from the British authorities.

Military chiefs hope that Iraqi tribes, who may anyway be ill-disposed towards Saddam Hussein's repressive regime, may take in any airman forced to eject from his plane, give him food and water and even smuggle him to the border.

And in a culture where hard cash counts for more than paper money or credit cards, gold is thought to be the best means of encouraging such aid.

Also in the waistcoat are a radio and strobe light for attracting the attention of search and rescue teams, a Global Positioning System unit to establish the airman's precise location, and a Walther PPK handgun with two magazines of ammunition.

The note - topped by a royal lion and unicorn crest of arms and a code number - assures whoever finds the downed airman that he means them no harm.

It reads: ''I am British and I do not speak your language. I will not harm you! I bear no malice towards your people.

''My friend, please provide me food, water, shelter, clothing and necessary medical attention.

''Also, please provide safe passage to the nearest friendly forces of any country supporting the British and their allies.

''You will be rewarded for assisting me when you present this number and my name to British authorities.''