IT SEEMED like a great idea at the time. When Lockheed Martin won the contract in 2001 to develop what became known as the F-35 Joint Strike Fighter, the aim was to produce a relatively cheap tactical aircraft with radar-beating stealth capability that would replace at least four other types in service. The biggest military programme in history would not only provide the backbone of America's fighter fleet for the next 50 years but would also bring in sales from the United States' closest allies. At least 3,000 F-35s would be ordered from the outset (over 2,400 by America alone). The result would be huge efficiency savings, initially from the scale of production and subsequently from the Southwest Airlines model of running just one basic type of aircraft across 90% of the fleet. Deliveries of operational aircraft were meant to begin in 2010.

Things look less rosy a decade on. The F-35 is now unlikely to enter service before 2016; programme costs have risen to more than $380 billion; the average price of each plane has nearly doubled; and the Pentagon now thinks the F-35 will be a third more expensive to run than “legacy” aircraft, with lifetime costs of $1 trillion. Senator John McCain calls the project “a train wreck”. Even supporters, such as Robert Gates, the former defence secretary who was forced to restructure the programme last year, reckon numbers may have to be cut.

What should be done? The radical answer would be to abandon the entire F-35 programme. But it is too late for that: it would mean America relying on updated versions of aircraft based on 40-year-old designs. However, the size of the planned order for what is almost certain to be America's last manned strike fighter makes little sense and should be cut.

One immediate priority should be cancelling the jump-jet variant of the F-35 for the Marines. It has been the main cause of the technical and weight problems that have bedevilled the programme. Having been put on two-year “probation” by Mr Gates in January, this version should be put out of its misery.

Over sea and air—but with a relatively short range

With the air force and navy versions of the F-35, the debate is more nuanced. Although a far more capable aircraft than those it is replacing, it may not be useful enough for long enough to justify the size of the planned order. Analysts question whether it is as stealthy as claimed and its ability to penetrate the best future air-defence systems. And to be as stealthy as it is, the F-35 can carry only two air-to-air missiles. The head of the air dominance branch of the Air Combat Command says he “wakes up in a cold sweat” thinking about it.

The F-35's range of around 600 miles (1,000km) is another problem. The potential adversary that will dominate American military planning in the decades ahead is China. Even now, China is acquiring weapons, such as accurate anti-ship ballistic missiles, that will push American carriers out into the western Pacific, well beyond the range of seaborne F-35s. For all its sophistication, against a “near peer” opponent the F-35 may not be able to do the job for which it has been intended nearly as well as the next generation of pilotless armed drones and hypersonic cruise missiles. Indeed, it could be obsolescent only a few years after it enters service. At a time of shrinking defence budgets, the F-35's huge cost and the affection of service chiefs for fast jets flown by brave chaps should not be allowed to crowd out the development of more capable weapon systems. Cut back the F-35s and spend the money there.