The price tag for the Lockheed Martin F-35 Joint Strike Fighter (JSF) has jumped 27% since the programme’s original baseline estimate.

Average unit procurement cost has risen from $50.2 million to $69.3 million, based on 2002 dollar values, says Maj Gen Charles Davis, JSF programme manager.

Davis, who spoke to reporters via teleconference today, attributed 92% of the cost increase to four factors: fewer planned aircraft purchases by the US military, inflation, a spike in titanium costs and the added overall costs to manufacturer the stealth fighter.

Even as the average cost to buy the F-35 rises, the estimated price to support the jet is falling.

The latest selected acquisition report released on Monday by the US Department of Defense (DOD) shows that the programme’s overall cost estimate has slightly declined.

Those figures stand in contrast to a recently published estimate by the US Government Accountability Office, which projected the programme’s overall cost had jumped about 10% since 2006.

DOD officials are currently considering an option to buy the next 12 F-35s for the second lot of low-rate initial production.

The purchase would include six conventional takeoff and landing F-35As and, after the short takeoff and vertical landing (STOVL) variant flies, perhaps six F-35Bs.

Lockheed plans to fly the first F-35B in conventional mode in late May or early June, and complete the first flight in STOVL mode with the lift fan system engaged by the end of the year.