F4U's torque

[Enduro]

Okay, this post isn't meant as a whine at all.  

We all know that the Hog's engine was a torque monster.  But, I'm wondering if the torque in our Hog is just a bit overmodelled.  I'm referring to the tendency of our Hog to loop after landing with an idle throttle.

Isn't the tendency just a bit much?  Maybe not.  Just askin'.

[Ghosth]

Helps if you "lock" the tail wheel by pulling half back on the stick. Tricky part is timing it right, too early and it try's to fly again.

To late and your already into the first swerve that leads to the ground loop.

And no, I don't think its overmodeled.  

[Wilbus]

The "swing" on landing and takeoff isn't caused by tourque actually. It's caused by the slipstream from the propeller hitting the vertical stab, this is why rudder helps to counter it. All planes have it, specially when taking off as you throttle up.

Tourque is a totally different thing, usually misstaken for the slipstream. Some planes wityh big engines (possibly the best known, Skyraider) could flip all over on iot's back if the throttle was moved up too fast. The tourque is countered by ailerons which is why you can only counter it with some airspeed. The tourque is also the reason your plane is rolling if you climb straight up and lose speed.

If anything, the tourque in the F4u is undermodelled IMO.

[FiLtH]

I do this. Come in slow, 2 notches flap, and when yoyu touch..PUSH FORWARD on the stick keeping your tail OFF the ground. The brakes will slow you down as you do this. Just when you feel you cant keep it off its tail any longer, pull back hard on the stick, slamming the tail down. You will stop before any weird crap happens.

[Knite]

The F4U is so much fun to take off and land.

Especially a carrier landing with 1 missing flap, and 1 destroyed gear.

;-)

[lasersailor184]

The trick to landing all airplanes is the C and V keys.  Set them to be left and right brakes.



I haven't rolled a plane in a year and a half.

[Enduro]

Ah, Lady slipstream, eh?  Well, remember that I'm talking about an aircraft with its throttle at full idle here.  Is the slipstream effect so apparent in the Hog when it's very slow & dirty?

Another question, then...why is slipstream so apparent in AH2's Hog and barely noticeable in the other a/c, like the 109, P-51 and Jug (when slow with idle throttles)?

[Angus]

Is it possible to key map the tailwheel lock?

[Wilbus]

The slipstream is just as noticable in the other planes (they wanna run of the runway on takeoff). However, part of the F4u ground looping problem may be the large tail fin.

Uhm, trying to explain tourqe to explain how it doesn't make a plane "sway" when on the ground.

When the prop is rotating, say to the right, it needs to something to counter the right way rotation (otherwise the prop would roll off and roll away to the right). The plane is it's counterweight.

So if the prop spins to the right the plane wants to spin to the left, this is what caused some planes to roll over on their backs when the throttled was opened too fast.

The slipstream from the prop causes the "sway" because the slipstream hits the vertical stab and thus pushes the tail end of the plane in one direction (depending on which way the prop is turning).

The tourqe is what makes the plane "spin" or roll at low speeds (specially noticable at the top of a zoom).

Enduro, I don't know how much slipstream is generates when slow and throttle on idle, shouldn't be THAT much so can't really explain that but ground loops (plane sway too fast and make a 180 or degree turn) "should" not be caused by tourqe.

Ever seen a car nose up when accelerating? Can be seen at dragraces, this is the effect of tourqe.

[MANDO]

To reduce the slipstream effect, try to reduce also RPM to minimum. Optionally, you may also stop the engine a soon as you touch the ground.

[peregrin]

The ground loop isn't necessarily cause by engine torque or p-factor etc.  Even low torque tail draggers have a ground loop tendancy.  The distance between mains and the tail wheel may be the most important factor for stability.

The way I land Corsairs to to three point them, by holding them nose up low over the runway until i stall out.  I tend to bounce down at 75 or so and can get it stopped quickly before any ground loop.

The other trick you can do is turn the engine off. (course that kind of refutes my earlier point)
--P.

[Morpheus]

51 needs more torque.

IRL you hit that thing to 100% and you'd dig the prop if you didnt roll the plane over on its back first.

[Simaril]

Originally posted by Enduro
Ah, Lady slipstream, eh?  Well, remember that I'm talking about an aircraft with its throttle at full idle here.  Is the slipstream effect so apparent in the Hog when it's very slow & dirty?

Another question, then...why is slipstream so apparent in AH2's Hog and barely noticeable in the other a/c, like the 109, P-51 and Jug (when slow with idle throttles)?

And is it just me, or do others have to apply rudder with manual take off in planes that ought not have slipstream issues at all -- like the Me262 and the P-38L?

[Whisky58]

Originally posted by Wilbus
The "swing" on landing and takeoff isn't caused by tourque actually. It's caused by the slipstream from the propeller hitting the vertical stab, this is why rudder helps to counter it. All planes have it, specially when taking off as you throttle up.
QUOTE]

If by "swing" you mean yaw then my impression is that torque does contribute.  Engine rotation causes roll which increases downward pressure on undercarriage on one side relative to other, which in turn increases friction/resistance between axle/wheel & wheel/runway on that side hence tending to turn plane towards that side.

Gyroscopic effect of rotating mass (ie engine) moving forward also has an effect but don't ask me to explain this as it needs someone with a brain the size of a small planet.

[MrRiplEy[H]]

I'm pretty sure most people think the planes are modelled way more sophisticated in AH than they really are.

The swing on landing is simply a bug IMO. If I recall it correctly it can do it even with a blown out engine on landing.