What lessons does the Boeing C-17A Globemaster III hold for the Lockheed Martin F-35B?

Both were placed on probation relatively late in their development cycles. Both hit technical difficulties, cost overruns, delays and barrages of criticism.

Acquisition programmes are prone to a kind of death spiral. Costs increase, orders contract - and so costs ­increase again. But the C-17A is proof that this can be avoided - nearly 18 years after entering a two-year probation, the US Air Force now has more C-17As than it ever requested. The airlifter does its job, and for a price accepted by a growing list of customers.

The F-35B arguably entered probation in better shape than the C-17A did. After all, the F-35B's ­technical difficulties pale in comparison with the mishaps that plagued early C-17A tests. Poor reliability of lift system components has slowed F-35B flight tests, but the C-17A's wing broke at 80% of ultimate load, ­indicating fundamental design problems.

The biggest foreseeable risk for the F-35B is a fresh cost increase. What it lacks most of all is stability - earlier this year the Department of Defense slowed production, and it may do so again next year. By comparison, the C-17A's recovery began after the DoD agreed to buy 40 C-17s through the probation period.

There is never a sure bet in the aircraft industry, but no programme can survive if it is set up for failure.

Source: Flight International