>>3237386 (lb)

That implies hostile(s)/traitor(s) from at least one of:

1) maintenance or ordnance crews

2) parts, flight software or ordnance distribution/control/security

3) someone with access to pilot or pilot personal equipment

4) parked aircraft security team

5) aircraft/systems design/test team

6) hostile ground fire near/on US base

7) orbital anti-air asset

Hope it was just pilot error, but doubt it, given the timing just after first use of F-35 in combat.