The Ministry of Defence was strongly criticised by MPs today over the "flawed" decision to switch fighter aircraft for the Royal Navy's new carriers .
It was announced in the 2010 Strategic Defence and Security Review that the Government would adopt the carrier variant of the US-built F35 Joint Strike Fighter rather than the "jump jet" version chosen by the previous Labour government.
Ministers argued that the carrier variant was a more capable aircraft and that it would increase "interoperability" with other navies - even though it meant mothballing one of the two carriers on grounds of affordability.
However last May, Defence Secretary Philip Hammond announced the MoD was reverting to the jump jet version amid fears the costs of fitting the necessary catapults and arrestor gear - "cats and traps" - were spiralling out of control.
In a highly critical report, the Commons Defence Committee said the 2010 decision to go for the carrier variant was a mistake which led to increased costs and further delays to the carrier programme.
"It is clear that the decision was rushed and based upon incomplete and inaccurate policy development. It was taken without the MoD understanding how the change could be implemented," the committee said.
"Perhaps the primary example of how little the MoD understood about this decision is the fact that it was supposed to improve interoperability. This turned out to be incorrect.
"We urge the MoD to learn the lessons of this closed, rushed and flawed decision of 2010."
The committee also complained that the lack of a proper defence industrial strategy put the UK at a disadvantage compared with competitor countries.
It said that such a strategy should combine a commitment to maintain the ability of the UK to act nationally with an understanding of where a level mutual interdependence or partnership with allies is acceptable.
"We do not understand how we can have confidence in a national security strategy which does not show a clear grasp of what is needed for the defence of the United Kingdom, and how this can be ensured," the committee said.
"The overriding reason for the purchase of any item of defence equipment must be its quality and the requirements of the armed forces. We consider nonetheless that the Government should take into account in buying equipment the enhanced opportunities for export of equipment in use by UK armed forces."
Defence equipment minister Philip Dunne said the MoD's newly published 10-year equipment plan would ensure the armed forces get the hardware they need in the years ahead.
"The increased financial contingency will help cover future risk and make our equipment programme affordable. There is also greater information for industry about our priorities, helping them to invest in the future capabilities our troops need," he said.
He insisted that the switch to the carrier variant of the F35 had been "right at the time", but that "unacceptable cost growth, technical risk and project delays" meant the decision to revert to the jump jet was "in the best interest of defence".
Shadow defence secretary Jim Murphy said: "This is another blow to the country's confidence in the Government's competence on defence.
"Days after confusion and contradiction on defence spending the chaos of the aircraft carrier decision is laid bare.
"This wasted time and money led to a serious capability gap and exposed lacking knowledge of defence procurement.
"The UK has paid at least an extra £100 million to have no aircraft to fly from an aircraft carrier for years.
"This is an important report. Industry have warned that without a defence industrial strategy tens of thousands of jobs are at risk and now influential experts outline the damage and competitive disadvantage brought by its absence.
"There is a loss of skills, contradictions in export policy, worries over investment in science and no strategy to support sovereign capabilities.
"A new industrial strategy must improve the speed of procurement, share the burden of risk with industry, support small businesses and strengthen collaboration between companies, the Department and the military.
"Labour has consistently called for a defence industrial strategy and our procurement review chimes with this report's analysis. Ministers must respond, listen to these arguments and change course."