By Nick Childs
BBC world affairs correspondent
Concerns over the contract for the eight Mark 3 Chinook helicopters, which still cannot be used operationally, are longstanding.
The new Chinooks were supposed to be ready for use in 1998
In the latest warning, the Public Accounts Committee has said there is an "alarming" shortage of battlefield helicopters, with the gap between the number of helicopters needed and those available to the Ministry of Defence as between 20% and 38%.
But those concerns also fit into a pattern of broader concerns about the Ministry of Defence's management of major programmes and the British taxpayer's money.
The National Audit Office and various committees of MPs have voiced alarm that projects like the Royal Navy's new Astute-class nuclear submarines, and Nimrod and Eurofighter projects.
There was the saga over the SA80 rifle.
And, going back to the 1980s, there was a previous version of the Nimrod which was scrapped at the cost of over £1 billion when it could not be made to work.
The Ministry of Defence insists it has learnt lessons from all of these.
The Labour government instituted what is known as Smart Acquisition, meant to streamline defence procurement. But its effectiveness remains an issue of controversy.
There are complicating factors.
Multinational projects like the Eurofighter have the virtue of spreading costs - but having to satisfy multiple customers and governments can add to the problems.
Many of these projects are also at the cutting-edge of technology and therefore high-risk.
And, what's more, the changing security situation in recent years has often meant that the specifications for some major weapons programmes have had to be drastically rewritten, adding to costs and delays.
Other countries are by no means immune. Major US-led projects have hit problems.
Ironically, one such programme, the Joint Strike Fighter (JSF), is having an impact on the British armed forces as well.
Britain is a major partner in the project and plans to buy 150 of the planes for the Royal Navy and RAF.
Troops reported problems in action with the SA80 assault rifle
But development problems mean that the introduction of the JSF has already had to be delayed.
Overall, by most accounts, Britain has very capable forces with highly-trained personnel and some very advanced equipment.
They may be tiny by US standards, but they have greater reach and probably capabilities than any of Britain's European allies except France.
At about £26.5bn last year, Britain remains one of the bigger spenders on defence, according to the International Institute of Strategic Studies.
But the concern expressed by critics of the Ministry of Defence is that it is still not getting a good return on that money.
It is a concern exacerbated by the fact that the budget is much tighter now than it used to be.
The British strategy is also to emphasise high-tech weaponry, in part in an effort to keep up with the Americans so that British forces can continue to operate alongside US forces.
That can be expensive - and as costs go up on some projects, savings have to be found elsewhere.
As well this week as the Public Accounts Committee report on helicopters, the House of Commons Defence Select Committee has warned of an emerging "capability gap" in the armed forces.
It says current equipment is having to be retired early in order to help pay for new weapons which may still be years from entering service.