The Joint Strike Fighter is on track to meet its 80 percent mission-capable rate requirement by the end of 2019, according to the F-35 program executive officer. After testifying in front of the House Armed Services tactical air and land forces subcommittee today, Vice Adm. Mat Winter told reporters the program is slated to achieve the benchmark because of modifications made to older aircraft and the ability to obtain spare parts. "So we're putting the repairing demand signal into our...