UK to pay £300m for 'fail-safe' bombs

Britain is to spend more than £300m on the world's most advanced "smart" bombs, which are designed to avoid civilian casualties by disarming themselves if they go off target.

Paveway IV bombs are to be fitted with a revolutionary, delayed fail-safe device called "Late Arm", which ensures stray bombs do not explode. They will also be armed with "insensitive munitions", which can only be detonated by a fuse.

The precision "fire and forget" bombs will use an advanced version of existing global positioning systems to find their targets. The system is said to have less chance of jamming or being adversely affected by weather.

The Paveway IV, a joint American-British design, is the next generation of the Paveway II and III series already in use with the RAF. But, at 500lbs (230kg), it will be a quarter of their size. The bomb will be manufactured atcentres in Portsmouth, Brighton and Glenrothes in Fife, by the British branch of the US company Raytheon. The work, according to the company, will create 200 jobs.

The initial contract with Raytheon is for £120m to supply the bombs. But the overall package, including fitting them to the RAF and Royal Navy's Tornado GR4s, Harrier GR9s and new Typhoon Eurofighters, will cost more than £300m. The bombs are expected to enter service in 2007.

After the Kosovo war, the Ministry of Defence admitted that laser "smart" bombs in use at the time had a high failure rate in bad weather. In the Iraq war, the RAF is believed to have exhausted half of its stock of Paveway bombs.

Lord Bach, the Defence Procurement minister, said yesterday: "'Late Arm' will send a message to the fuse two seconds before impact confirming it is on course, serviceable and not being jammed. If any of these conditions are not met, the fuse will not arm and the warhead will not explode."