Service chiefs are cutting too many corners and taking too many risks in their efforts to bring expensive new weapons systems into operational use before they have been properly tested, it concludes.

"Cost and schedule pressures are increasingly causing programme managers to accept more risk and it is showing up as performance shortfalls in operational testing," says the author of the annual departmental report, Philip Coyle, who resigned as the Pentagon's director of testing and evaluation in January.

The report is scathing about the increasing failure to test weapons systems properly, an issue at the centre of the argument about the government's plan to erect a multibillion dollar missile defence shield to protect the US and its allies from attacks by "rogue states".

Mr Coyle says that earlier tests of the missile shield were too simple to allow a properly informed decision whether to move from the current research phase to deployment, as the administration has made it clear it intends to do.

The missile defence test programme is "not aggressive enough to match the pace of acquisition to support deployment and the test content does not yet address important operational questions," the report says.

It makes it clear that the armed forces' desire to bring modern hi-tech weapons on stream is consistently running ahead of the proof that they can actually do the job for which they are intended.

The failure to submit new systems to adequate testing has caused repeated delays in all the armed services, the report says. "The impact of reductions [of testing] can be seen in the doubling of army systems that failed to meet reliability requirements," Mr Coyle writes.

In recent years 66% of all US air force programmes have had to stop operational testing because the system under test was not in fact ready for testing "due to some major system or safety shortcoming", the report says. In the past five years 80% of army weapons and equipment programmes have failed to achieve even half of their "reliability requirements", it adds.

The report is especially critical of the way in which the increasingly ill-fated and hugely expensive V-22 Osprey vertical takeoff aircraft programme has been allowed to get so close to deployment with so many basic safety and reliability issues unsolved.

The Osprey, which crashed twice last year killing 23 US marines, is a revolutionary cross between a helicopter and a plane. It is intended to replace the current generation of medium lift assault helicopters.

Tests were reduced "due to cost and schedule pressures", the report says. Instead of carrying out the planned 103 tests of the controversial tilt-rotor plane, the marines first cut the number to 49 and then conducted only 33.

Rather than test the Osprey's reliability under icing conditions or under air combat simulations, the US navy issued waivers to cancel the tests.

The report's criticisms of the national missile defence (NMD) programme come at a time when President Bush has ordered his defence secretary, Donald Rumsfeld, to conduct a review of defence strategy and needs, including the role of NMD.

It is expected to recommend a central role for a more extensive NMD system than the one that was tested under the Clinton administration.

The report is highly critical of the adequacy of the testing programme to which missile defences were subjected as part of the Clinton administration's more limited programme to examine the feasibility of a land-based system of about 100 anti-missile interceptors based in Alaska.

Unsuccessful NMD test intercepts in 1999 and 2000 were not only failures but were dogged by "considerable limitations" in reliability, Mr Coyle says.

These included a failure to achieve "realistic engagement conditions" with respect to radar tracking, range, intercept altitude and closing velocity, as well as other features.

The tests were of limited use, because they simulated "only unsophisticated counter-measures, such as simple balloons". In real combat, the report says, hostile missiles would be equipped with much more elaborate and effective decoy systems.

© Guardian Newspapers Limited 2001

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