Pratt & Whitney is running the numbers on how much the Pentagon could potentially save on the propulsion side by block-buying the Lockheed Martin F-35 Joint Strike Fighter and moving to a performance-based logistics arrangement (PBL).

Speaking at the Paris Air Show, P&W F135 engine program chief Mark Buongiorno says the company intends to respond the DOD’s request for a “rough order of magnitude” estimate of the potential savings form bulk ordering aircraft as the programme partners mull a three-year deal covering procurement in fiscal 2018-2020.

Pentagon acquisition executive Frank Kendall said in May that he hopes to see “double-digit savings” come from a 450-aircraft block buy, and now industry is now assessing how it might achieve that level of savings while also cutting the fifth-generation jet’s costs through other measures, like Lockheed Martin’s “blueprint for affordability”.

“Overall you’re going to see the weapon system achieve a pretty robust savings when you look at the number of dedicated facilities on the airframe and some on the propulsion side that really do benefit from that kind of increased volume,” Buongiorno says. “They can make investments when you get to that level of volume and have multiple sources as well. Could it hit double digits? It quite possibly could.”

The programme has also agreed that incentivising industry performance in the sustainment phase through a PBL contracting structure would be better long-term, and Pratt says it working some “goal-aligned aftermarket contracting strategies” with the joint programme office.

Buongiorno says the programme could transition to a PBL around 2019.

P&W believes there are savings to be gleaned from a performance-based approach on top of other affordability measures, like life-extension programmes to cut the number of engines overhauls that are needed. Buongiorno pointed to the successful life-extension of the F100 on the Lockheed F-16 and Boeing F-15 that cut one out of every three overhauls. “That translates almost directly to a 30% reduction in sustainment costs,” he says.

Pratt has delivering 228 F135 engines to date as well as 63 Rolls-Royce lift fans.