"The Marine Corps conducted an assessment of F-35B austere site deployed operations at Twentynine Palms, California, from December 8 – 16, 2015, with eight F-35B aircraft assigned. The Marines intended to fly four aircraft a day from an expeditionary landing field made of aluminum matting and with minimal permanent infrastructure, representing the type of temporary airfield that can be quickly built near the forward line of troops. The demonstration included the use of inert ordnance and production representative support equipment. Aircraft availability for this detachment was again in the 55 to 60 percent range, which led to a significant number of missed flights on the planned flight schedule. The detachment flew 41 out of 79 planned missions; however, 22 of the 38 missions not flown were due to high crosswinds which made landing and taking off from the aluminum matting too risky. Overall, 16 missions were lost due to either lack of aircraft availability, difficulties in transferring and accepting aircraft data into the deployed ALIS, or ground aborts. Propulsion system maintenance was particularly burdensome. Two F-35B aircraft received foreign object damage to their engine fan stages, a result from operating in rugged conditions with jet wash likely blowing small rocks into aircraft intakes. This prevented those aircraft from further participation in flying activities until repairs were completed just prior to the ferry flights home. A contractor technician was called in from the East Coast and was able to repair the engine damage on site, as opposed to having to perform a full engine swap. A further engine system discrepancy required an aircraft swap around mid- way through the detachment. Routine flight operations, such as aircraft start-up and basic troubleshooting, also relied heavily on contractor maintenance."