US Government Accountability Office | Apr 15, 2019
“In total, the program participants plan to purchase more than 3,300 F-35 aircraft, with the U.S. services planning to purchase nearly 2,500 of those aircraft.” – page 5
And a few excerpts from the summary:
“F-35 aircraft performance is falling short of warfighter requirements—that is,
aircraft cannot perform as many missions or fly as often as required.
This lower-than-desired aircraft performance is due largely to F-35 spare parts
shortages and difficulty in managing and moving parts around the world”
“DOD has spent billions of dollars on F-35 spare parts but does not have records for all the parts it has purchased, where they are, or how much they cost.”