YES!!! I know what you are trying to say.
Pulling the PLs behind flight idle is not very smart... I know Fokker have made some computer analysis of "What will happen if I pulled the PLs into Ground Idle during flight?" The result was that IF the WOW-switch and the relees (?) in the pedestal fails, so that someone accidentally pulls the PLs to Ground Idle during flight, the airplane would lose some 20 000 ft in the recovery -
IF the wings don't fall off. -Which they probably will.
What I am saying is, that I know that, for instance the Dash8 or a Beech King Air 200 has a larger drag (thus steeper descent profile) when the PLs are in flight idle than the Fokker 50. Similarly, a Cessna Caravan can keep almost Vmo till 5 miles final because of the extreme air-braking obtained when pulling the PLs to Flight Idle.
Thus - If the aircraft needed greater "air braking capability" it would be easier to make the aerodynamic drag from the propeller blades larger at Flight Idle, than making an extra, technically advanced and expensive air brake in the aircraft tail or on the wings.
To ensure that "speed brakes" is not used at normal descent, there could be 5 detent positions on the PLs:[list=1][*]Max detent[*]Flight Idle[*]"Air brake"[*]Ground idle[*]Reverse[/list=a]
Just a suggestion to the aircraft engineers.
Any comments other than
?
We should have some of the engineers who are usually on "Tech log" to look at this. I will demand royalties
!
Nick.