I flew the Dash for about 12 years. About 3 of those without a beta warning horn system. Around 1999(?) Bombardier introduced the beta warning horn, incorporated into the throttle triggers.
The triggers at the flight idle gate prevent the power levers from moving into discing mode (from memory, a beta mode). At the back of discing is a detent (not a gate), then you move into reverse mode.
In the background info distributed at the time, it was emphatically stated that the selection of discing in flight (inadvertent or otherwise) could lead to a complete loss of propeller control. Hence the introduction of the beta warning horn system. The prohibition in the AFM has always been so, and was re-emphasised in the bulletin.
Jabber, even at VMO with the condition levers at max, a normally functioning prop governor on the PW120 series engine will keep the prop at around 1200rpm. It's not an issue. In climb, cruise, descent and till late approach - the props are running at 900 or 1050rpm. Max isn't normally selected until late final.
Interesting..........
Last edited by Hugh Jarse; 12th Nov 2011 at 03:03.