It is always interesting to read the comments of airline pilots, real or simulated pilots, to the prospect of flying an aircraft with engines U/S or never installed in the first place (gliders). You have to get the approach and landing right every time. From the moment that the instructor gets out of the back seat and tells you to get on with it, the only weapon to deal with an undershoot situation is to put away the Airbrakes (Spoilers). As did the Captain of the 777 at LHR when his engines declined to spool up at a critical moment.
Three times in my flying I have noticed completely unbelievable readings on the ASI. I followed the basic rule of flying number one, first of all, if the aircraft is still right side up, Do Nothing. Avoid panic. Think about it. Realising the problem (I had left the static ports covered with tape) the two options left were to fly by attitude, and the sound of the airflow. Being fortunate enough to have plenty of height, and experimenting gently with these remaining indications of airspeed, made presentable landings back at base.
A third problem that has occasionally brought down an airliner, was an inoperative control, namely my ailerons were frozen. Quite literally, as the tape on the wings got wet the previous night, and I was at 20,000 feet. (in wave, at Aboyne).
Same drill. Do Nothing, avoid panic, think about it. Solution, gentle turns with rudder alone, and descent to warmer air.
Its a shame that the beancounters and those dependent on engines don't realise how valuable the experience of basic flying in simple aircraft can prove. Of course sim training gets you accustomed to complex panels and alarm systems. Unfortunately in this training your butt is never truly in danger, only your coreer.....