The following are damaged/out:
Engine 1
Engine 1 Oil
Engine 1 Radiator
Right Flap (
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, but not the issue)
Procedure:
Engine 1 is dead, due to combat damage. Fly back home and land, during the flight the throttle works as normal controling the right/good engine. I land and shut down the engine(s) with "E", no response from the game. I hit Shift+1, no responce as expected for a dead engine. I hit Shift+2, hit E again, and it shuts down. I started Engine 2 again, then selected Shift+E followed by E, and nothing.
When engine 1 is out, engine 2 seems to isolate from the "all-engines" functions (although I have not tested if there is any bug/issue with both engines in working condition).