Originally Posted by
sheppey
Know nothing about KingAir throttle friction nuts. Therefore showing technical ignorance here. But if its job to prevent the throttles from falling back if your hand is removed, wouldn't the pilot merely keep the two throttles up at take off power manually instead of removing his hand from there during the takeoff roll?
Basically, yes. Although at some stage, as mentioned previously, your hand comes off the power levers so that you can raise the gear. Whether you do this at V1 or some other point depends on the way you operate it. The simple fix for when the lever slides back is to put your hand back on the lever and push it forward again, gain some altitude then tighten it up and get back to normal flight. This is why I say "it shouldn't happen", but stick with me here and the following scenario highlights how it can.
Power is set, barrelling down the runway. V1/positive rate (depending on your technique, I use the latter) you take your hand off the power levers, you need that hand to get the gear up. Now at this moment a lever slides back (typically the left lever), it could maybe go back half way or all the way to idle, depending on just how loose the friction is. It can happen at a rate that feels like an engine has failed, trust me on this I know, I've had it happen.
now in this moment when you think "engine failure" you should put your hands back to the power levers and realise what has happened. But instead due to the initial "oh ****" moment you grab the control wheel; thinking max power is set on the live already, auto feather has got the "failed" one covered, and away I'll fly. Nope, autofeather will not feather the prop because the system requires power lever position switches to be made- ie power lever forward (I can explain the system in more detail if you want, or search back in the thread it's already been discussed). Now you have a prop spinning at a rate that isn't providing usable, or even zero thrust. It's making a lot of drag. Your struggling to fly the plane away, focussed on the airspeed and trying to keep the wings level, and eventually your performance degrades so much that you crash.
as I said, it shouldn't happen. But humans make mistakes and mishandle aircraft, so being forewarned about it can maybe save someone in the future. As I said in my initial post on this subject, I'm not suggesting this is the cause of this accident. I rather brought it up so that people who didn't know about it learnt about it.