PT6 Question

[Lefthanded_Rock_Thrower]

When using reverse inflight, yes it is legal in a few types.

The Governor will not allow the blades into reverse until there is an underspeed condition, usually achieved by power lever into reverse at low airspeeds.

Q: if you were to bring the power lever into reverse then prop RPM into low RPM, then back up to high, would this underspeed condition be sufficient to put the prop into reverse, is there any adverse effects to this practice ( i.e. higher than normal oil flow etc etc ).

[180 Too Fower]

Hi there.....it may be legal in a few types but is it sensible and safe:uhoh:

I can't think why anyone would want to try or experiment using reverse in flight, in fact it sounds utterly stupid and dangerous to me, and I do have over 2000 hrs on King Air's.

My advise to you is....leave this idea of yours alone and go and get a nice book to read and stay away from those levers :ok:

[411A]

In the very early days of DHC-6 ops in the USA, it was sometimes the policy of a few pilots to try beta and/or reverse in flight, with the prop controls in the normal cruise position.
This enabled rather fast straight-in approaches to be flown, yet stop in short distances.
However, altho the props would indeed transition into beta/reverse, they would do so not necessarily together (altho selected at the same time), with oftentimes undesired (and quite surprising) results...:ooh: :ooh:
This practice was, of course, well before the AFM was amended, to prohibit this action.
During training in this aircraft, deHavilland pilots demonstrated (and taught to those that wanted to know how) the procedure whereby one could approach a runway at 1200agl, props full forward, flaps set to 40 degrees and, over the threshold (still at 1200agl), select reverse, descend, land and stop in 1000 feet...maximum.
Quite a hoot, but you had to be very careful, during the roundout, to be sure that reverse was de-selected, otherwise the hole you would find yourself in would be rather deep.....:oh:

[Lefthanded_Rock_Thrower]

180, i haven't and wouldn't do it in a B200, it's illegal ( refer Flight Manual ).

Parachute operations in a PAC Cresco ( PT-34A ), reverse inflight is allowed by both the engine and airframe manufacturer, so it is not as idiotic as you incorrectly believe.

My question still stands: when selecting reverse off the top of a parachute run ( for example ), one must wait until the airspeed decays to below 80 knots before the prop goes into a underspeed condition, which allows reverse to be selected, can the reduction of Prop RPM then selection of Reverse, then increase of Prop RPM lever ( forward), will it simulate the required underspeed to allow selection of reverse at higher airspeed ?, is there any other issues relating to this type of operation.

Note: the underspeed condition required is derived by the propellor speed ( actual NP ) versus the Prop lever position.