Equipment used by UK troops on last year's military desert exercises in Oman failed to work properly and fell apart in high temperatures, it has emerged.

A report by the National Audit Office found that tanks, helicopters, guns, lifting equipment, boots and clothing all struggled in the desert heat and dust.

Some problems

Tank filters clogged Ageing radio system "incapable" AS90 gun filters melted Helicopter parts unserviceable Lynx rotor blades lasted just 27 hours SA80 rifles jammed Shortage of forklift trucks Boots melted or fell apart

Such shortcomings suggest Britain may have difficulties if, as increasingly speculated, it joins a possible US-led land invasion of Iraq.

David Clark, leader of the NAO report team, told BBC Radio 4's Today programme the operation had been a success in many ways but there were some "very significant" problems.

Liberal Democrat defence spokesman Paul Keetch said the shortcomings were "nothing short of a disgrace".

But armed forces minister Adam Ingram told Today the report described the operation overall as a "major success" - proving that the UK could successfully deploy a rapid reaction force overseas.

"The purpose of the exercise was to see if there were any weaknesses... that's what an exercise is about.

Tanks clog up

"It confirms things we knew were happening at the time. It puts on record that which we now need to address, some of which was already being addressed anyway.

"There are major upgrade programmes in place, major replacement programmes in place. These things don't happen overnight - they do take time, they need funding."

The SA80 rifle jammed

The report said the most severe problems were with the Challenger 2 tanks, which would be expected to spearhead any assault by British ground forces.

Dust clogged up the tanks' air filters so that they ground to a halt after just four hours service.

The army's ageing Clansman radio system - due to be replaced in two years time - was so useless tank crews had to stop and get into a "huddle" to communicate with each other.

Troops could not resort to mobile phones, because there was no cover in the desert.

Rotor blades on the Lynx helicopter, which would normally last for 500 hours... needed replacing after just 27 hours

National Audit Office

The plastic air filters on the mobile AS90 self-propelled guns melted in the heat, the NAO reported.

Almost half the helicopter fleet was out of action at any one time as parts quickly became unserviceable.

Rotor blades on the Lynx helicopter, which would normally last for 500 hours flying time in European conditions, needed replacing after just 27 hours.

The SA80 rifle jammed. The new, modified SA80-A2 was not used on the exercise.

'Very pleased'

Fork lift trucks had no maintenance contractors so became in short supply, and some other vehicles were so old they threatened to overheat if used for more than short periods.

We will make improvements to our equipment and procedures

Ministry of Defence

There was a shortage of desert combat suits and boots, and normal army boots melted in the heat. When extra desert boots were found from old war stocks, some quickly fell apart and some troops developed foot rot.

The exercise also suffered from shortages of key specialist personnel, including engineers, signallers, intelligence staff and medics, found the NAO.

The Ministry of Defence said nevertheless it was "very pleased" with the way both people and equipment had performed overall.

It said it was the first time much of the equipment had been tested in operational desert conditions.

"We have made comprehensive arrangements for identifying lessons and, where necessary, we will make improvements to our equipment and procedures."