Like I said, fancy new upgrades for unmanned drones that can handle very high G forces.
https://freerepublic.com/focus/f-news/1342535/posts
Yes the Harrier DOES turn at a right angle. Do a search for “turns a square corner” on that link. Much less reason to take your word for it than someone who was flying a chase plane behind the Kestrel.
You're taking it waaay too literal. Vectored thrust will let it make sharper radius turns, but it isn't coming to a stop and changing direction 90'.
That’s a picture of a Harrier from the side during a vertical landing. FLIR is FORWARD Looking Infrared and the plumes would be hidden by the Harrier’s wing.
They object they track (while they are in a turn) rotates and never shows exhaust plumes.

You're taking it waaay too literal. Vectored thrust will let it make sharper radius turns, but it isn't coming to a stop and changing direction 90'.
That’s a picture of a Harrier from the side during a vertical landing. FLIR is FORWARD Looking Infrared and the plumes would be hidden by the Harrier’s wing.
They object they track (while they are in a turn) rotates and never shows exhaust plumes.
