[ThunderSleeps]

Strange. The -29 is a twin engine aircraft. You’d think if one engine failed it could limp back on just one. Then again, just after launch, low, slow, full of fuel and ordnance... Maybe he couldn’t jettison ordnance and dump fuel fast enough? Or if not an engine failure, some other flight critical system like fuel or a significant failure in the fly by wire system.

[pfflier]

The narrative is slim. It just said one jet appeared to have a mechanical failure and crashed returning to the ship.

Any number of flight critical systems could have been the cause.