Two things I'm struggling with with this aircraft at the moment.

1) Props full forward for touchdown. I find that if I do this, the spoolup time for a go-around is a lot longer. Also if I do it in advance of the touchdown, it makes riding the throttle harder for this reason. Plus it's something that gets in the way of me accurately touching down. What is it for and is it really necessary? I thought it was for prepping the reversers, but the reverser works even without it full forward? Is it less effective? Because it's getting in the way of my landing so much, I'm thinking of ditching it... plus there's nothing in my checklist that says that after rollout, to bring the props back again (where they were when taxiing for departure, so one would expect them for taxi on arrival); my checklist is an almagamation of various checklists including the supplied one, so this omission is in line simply with what I have read...

2) I keep essentially stalling when I pull back from VApp to VRef resulting in me essentially falling onto the runway at touchdown. The VRefs are calculated by the accompanying tables; typically VRef for me is around 102, and then VApp is calculated accordingly, but it is VRef that I'm struggling with. I feel like it needs at least another ten, maybe fifteen knots. Anybody else found this?

EDIT: Perhaps the spoolup time is actually due to me reducing the throttles too far for a prop...

@skelsey perhaps you can shed some knowledge?

Edited August 2, 20187 yr by JKawai

Hello!

Treading slightly carefully and talking in general terms here because as I say, I am not familiar with the King Air specifically.

However, as far as operating aircraft with constant-speed propellers is concerned, it is usual practice to select full fine pitch (max RPM) at some point during the approach as this ensures maximum power is available in the event of a go-around. Withour getting in to a full treatise on constant-speed propeller operation, loosely one can think of the prop RPM control as vaguely similar to the gears on a car: when cruising, one selects a higher gear (lower prop RPM) for efficiency, but when rapid acceleration is required from low speeds a lower gear (higher RPM) is necessary.

One issue with selecting fine pitch is that it is very noisy - which is part of the reason it is generally delayed until late downwind/final approach. In a generic piston twin a common checklist carried out on the downwind leg (or equivalent position) is BUMPFFITCH - Brakes released, Undercarriage down and locked, Mixture full rich, Props full fine, Fuel sufficient etc, Flaps, Instruments, Ts & Ps green, Carb heat on, Hatches & harnesses secure. I'm not sure what the King Air procedures call for but I imagine something something similar would make sense.

One thing that can be an issue in turboprops, and prop engines in particular, is that if you pull the power back significantly you can end up with a 'negative torque' situation - i.e. the airflow is driving the prop rather than the engine. The props in this situation are effectively massive solid discs aerodynamically and create enormous amounts of drag. As a result, I am aware that many turboprops are actually landed with power on, unlike jets or single-engine piston aircraft, and perhaps this is pertinent to the King Air?

47 minutes ago, skelsey said:

Hello!

Treading slightly carefully and talking in general terms here because as I say, I am not familiar with the King Air specifically.

However, as far as operating aircraft with constant-speed propellers is concerned, it is usual practice to select full fine pitch (max RPM) at some point during the approach as this ensures maximum power is available in the event of a go-around. Withour getting in to a full treatise on constant-speed propeller operation, loosely one can think of the prop RPM control as vaguely similar to the gears on a car: when cruising, one selects a higher gear (lower prop RPM) for efficiency, but when rapid acceleration is required from low speeds a lower gear (higher RPM) is necessary.

One issue with selecting fine pitch is that it is very noisy - which is part of the reason it is generally delayed until late downwind/final approach. In a generic piston twin a common checklist carried out on the downwind leg (or equivalent position) is BUMPFFITCH - Brakes released, Undercarriage down and locked, Mixture full rich, Props full fine, Fuel sufficient etc, Flaps, Instruments, Ts & Ps green, Carb heat on, Hatches & harnesses secure. I'm not sure what the King Air procedures call for but I imagine something something similar would make sense.

One thing that can be an issue in turboprops, and prop engines in particular, is that if you pull the power back significantly you can end up with a 'negative torque' situation - i.e. the airflow is driving the prop rather than the engine. The props in this situation are effectively massive solid discs aerodynamically and create enormous amounts of drag. As a result, I am aware that many turboprops are actually landed with power on, unlike jets or single-engine piston aircraft, and perhaps this is pertinent to the King Air?

That is the most perfectly rounded and clear response I could have hoped for. THREAD CLOSED! 😄

(Honestly, it's rare on forums to get an answer that's even pertinent to the question in the OP let alone one as clear as yours, so thank you!)

3 hours ago, skelsey said:

Hello!

Treading slightly carefully and talking in general terms here because as I say, I am not familiar with the King Air specifically.

However, as far as operating aircraft with constant-speed propellers is concerned, it is usual practice to select full fine pitch (max RPM) at some point during the approach as this ensures maximum power is available in the event of a go-around. Withour getting in to a full treatise on constant-speed propeller operation, loosely one can think of the prop RPM control as vaguely similar to the gears on a car: when cruising, one selects a higher gear (lower prop RPM) for efficiency, but when rapid acceleration is required from low speeds a lower gear (higher RPM) is necessary.

One issue with selecting fine pitch is that it is very noisy - which is part of the reason it is generally delayed until late downwind/final approach. In a generic piston twin a common checklist carried out on the downwind leg (or equivalent position) is BUMPFFITCH - Brakes released, Undercarriage down and locked, Mixture full rich, Props full fine, Fuel sufficient etc, Flaps, Instruments, Ts & Ps green, Carb heat on, Hatches & harnesses secure. I'm not sure what the King Air procedures call for but I imagine something something similar would make sense.

One thing that can be an issue in turboprops, and prop engines in particular, is that if you pull the power back significantly you can end up with a 'negative torque' situation - i.e. the airflow is driving the prop rather than the engine. The props in this situation are effectively massive solid discs aerodynamically and create enormous amounts of drag. As a result, I am aware that many turboprops are actually landed with power on, unlike jets or single-engine piston aircraft, and perhaps this is pertinent to the King Air?

Only to add.....many, if not most, King Air pilots delay advancing the props until AFTER touchdown due to the noise making passengers uncomfortable.  Not terribly unsafe as long as torque limits are followed on a go around.  Some turboprops have higher torque limits at reduced RPM. 

1) This may come down to the lack of accurate turboprop performance in the sim regarding spool-up. In my RW experience, we always have the props high with/without pax onboard, then again I was not flying a typical civilian King Air and our re-written checklist's called for the props to be high.

2) At what point are you pulling the power back to flight idle? If I'm using 105kts, and at that speed 50' above the threshold, I'm still flying in ground effect as I try to grease it on without a stall horn sounding into say the high 80s. There is a difference between the flare characteristics of 3 and 4 blade props that I doubt are correct in the sim.