Its always worth remembering Davy's tip...

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It can often happen during a Multiplayer session when you are Typing in the "Chat Window"....

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You typed the letter "e"key BEFORE you opened the Chat Window, and froze one of your engines!...

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Keep an your on the Throttle Levers when Taxiing and coming in to land...and using the Chat Window (all sorts of strange things can happen then... Gear up/down, Flaps up/down, etc, accidentally!....Make sure the Throttles are both/all working...!
Paul...Throttling my Chat Window!...

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P.S. Pressing just "E", instead of "Ctrl+E" to start-up, can disengage one or more of the Throttles!..

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Win 8.1 64-bit. DX11. Advent Tower. Intel i7-3770 3.9 GHz 8-core. 8 GB System RAM. AMD Radeon HD 7700 1GB RAM. DVD ROM. 2 Terra Byte SATA Hard Drive. Philips 17" LCD Monitor. Saitek Cyborg X Fly-5 Joystick. ...and a Briggs and Stratton Petrol Lawn Mower.