THE seriously delayed and massively over budget Eurofighter Typhoon is so unreliable it is barely airborne, according to the German government, which has just taken delivery of a squadron of the £60m planes.
The new fighter-bomber, being jointly built by the UK, Germany, Spain and Italy, also lacks some of the most basic systems to protect it over the modern battlefield and has been plagued with technical problems.
A report prepared for the defence committee of the German parliament said that the eight aircraft bought for the air force spent an average of just one hour a week in the air because components had to be replaced so frequently.
German officials - whose reluctance to go ahead with the project in the 1990s delayed it by several years - have tried to play down the problems, but have admitted "teething troubles" with the new aircraft.
The report indicated that each aircraft had spent an average of only one hour in the air per week since they came into service last April. They also lack one of the most basic defences against missile attack - decoy flares.
The flares, which are often made from magnesium, are fired from aircraft and used to fool heat-seeking missiles.
The reason that the lack of decoy flares is so much of a concern is the fact that many terrorist organisations have access to shoulder-launched heat-seeking missiles which are easy to carry and use and can destroy an aircraft.
During the Cold War, the US and Soviet Union distributed thousands of the missiles to their allies, such as the US-backed Muslim fighters in Afghanistan and Soviet-backed Syria.
British MPs have admitted that they are concerned by the difficulties with the project. One blamed the large number of countries involved in the aircraft and suggested it was a matter of "too many cooks spoil the broth".
Tory defence spokesman Gerald Howarth, who has supported the plane as "a fantastic bit of kit" throughout its troubled development, admitted he was dismayed by the latest setback.
He claimed many of the problems experienced were the result of trying to involve too many countries in the project, rather than relying on UK industry to produce the plane.
"It doesn’t look good and it gives all sorts of people the chance to knock the project," Howarth told Scotland on Sunday. "I would have gone for a national construction programme, which would have prevented all these problems - but it is too late for that.
"I haven’t heard of any problems with the UK Typhoons - in fact everyone who has flown them says they are great machines. We just have to get more of them up in the air and keep them there."
The project has been plagued by rising costs and delays. The bill for Britain’s order of 232 aircraft to replace the RAF’s Tornado F3s and Jaguars has risen over the years from 7bn to 20bn.Germany will receive 180 aircraft, Italy 121 and Spain 87.
The aircraft was originally called the Eurofighter 2000, because it was due to come into service in 2000, but the number was quietly dropped in the late 1990s when it became apparent that the 2000 deadline would not be met.
The current name, Eurofighter Typhoon, was designed to be more dynamic and export-friendly, but the word Typhoon caused controversy because it recalled a famous RAF fighter-bomber of World War II which devastated German tank and troop columns.
In the early 1990s, German misgivings over the Eurofighter almost scuppered the entire project. Hit by the costs of German unification, Berlin considered opting for the Soviet-designed Mig-29s it inherited from the East German air force.
The end of the Cold War also led to Germany questioning the need for the plane.
German delays added to the costs of the project, and even after opting to continue with the Eurofighter, the Germans cut their orders for the new planes.
A spokesman for the Eurofighter project admitted that the first deliveries of fighters did not posses the decoy flare systems but said that future deliveries would have the flares and that air forces would be able to ‘retro-fit’ them to their existing machines.
He said claims that planes had been grounded because of a lack of spares were based on information that was current last November and that the problems were "rapidly" being addressed now the fighters were in service and that the plane was well-liked by pilots.
A spokesman for the Bundestag’s defence committee said that it could not discuss the contents of the report because defence reports were confidential.
However, a defence committee source, based in Berlin, told Scotland on Sunday that there had been a number of "issues" with the new aircraft, although they were the "normal teething problems".
A British Ministry of Defence spokesman said: "The MoD is unable to comment on the reports in the German media on their Typhoon aircraft."