Originally Posted by pitzel
Anyone notice that the fuel flow to the #1 engine was substantially different (ie: #1 engine was significantly throttled down)? As though the engines thrust is used to manouevre the aircraft. Unlike a conventional airliner that will effect rolls entirely with the ailerons and rudder and will only adjust engine output in response to loss or gain of speed.
At 0:59, #1 = 3275, #2 = 5274, #3 = 5281, #4 = 5568 and a corresponding reduction in the N1 and N2 turbine % indications. And the plane was clearly in a turn to the left. So those engines must be constantly throttling down and up all the time individually and independantly when they're flying as part of the stability control system.
Edit: If you go to 4:50 or so and keep watching, you see that the fuel flows are all over the place when they're approaching the tanker. That must be terribly stressful for the engines, gas turbines really don't being subjected to power setting changes all the time... An engine out situation could be a real giant problem in that airplane, unlike the B-52, KC-135, or 747 where they just shut the engine down, adjust the trim, and keep flying...
Edit: No sound in that video, but it must be annoying as heck as a pilot to have the computers doing thrust changes all the time..
If you're flying formation, thrust changes are made about every second. It's the nature of formation flying.
If a gas turbine can't handle that, it shouldn't be in a military airplane. Period.
Tanking is simply formation flying with contact between the airplanes.