The F-35 joint program office (JPO) announced Tuesday evening that it has reached an agreement with engine manufacturer Pratt & Whitney on two key milestones — identifying the root cause of an engine issue that caused a fire in June, and on a contract for the next lot of engines for the stealthy fighter.

It hasn’t been an easy summer for Pratt. In June, a fire broke out on an F-35A model, eventually leading the grounding of the fleet and a missed opportunity to give the jet an international debut at the Farnborough International Airshow.

Eventually, investigators concluded the cause of the fire were “microcracks” in the engine caused by certain flight maneuvers. The fleet has since resumed flying, albeit under restrictions that Bogdan has warned could lead to test delays if they are not resolved in short order. […]