lets talk torque

[bozon]

lets take a look at a scenario in which the speed drops off steadily - such as in a flat turn or a zoom climb.

what effects the net torque on the plane (in the roll axis)?
1. the torque through the propeller shaft needed to turn it against the air - creates a twisting force on the plane counter to the direction of the prop.

2. prop wash on the wings, secondary effect - the air flow corckscrewing around the plane's axis add lift on one side and reduce lift on the other. the direction is counter to #1. There's also some light turque applyed by the tail due to the corckscrew flow. The wing design and width at the root will affect this.

3. The total torque effects are negated normally by applying ailerons in the opposite direction.

4. how fast does torque actually rolls the plane depends also on the Inertia moment of the plane (how "heavy" it is to roll) and the length of the wings (that resist by creating or loosing lift as they move through the air down or up).

now, as the speed drops and approaches stall, the effectiveness of the ailerons in resisting the torque becomes smaller and smaller, until (if the torque is stong enough) full stick deflection will not counter it. This should prevent me from flying full throttle at near stall speeds.

I have a few hours in planes and helis and did the standard stall drills. They are always done with low throttle setting, probably due to the above reason and I remember loosing ailerons effectivity almost to nil near the stall.

In AH(II) I feel this effect in some planes such as the FW190 and bf109. these are light planes with very strong engines and narrow wings so all the factors work against them.
On the other hand I don't feel this on pretty much any of the other planes (spit XIV is exception). In stall fights I never fear slamming the throttle forward violently when I need the power. I can easilly counter any torque with the ailerons as long as I don't stall. I'd expect to feel it a lot more on planes like the P51, yak, or La7 as they are also light, small and with very strong engines.

Any experts have comments on the torque effects in low speed flying? How accurate is this modeled in AHII?

Bozon

[Red Tail 444]

have you tried it in an F6? Although you have plenty of warning, the departure characteristics are pretty nasty. the Corsair snaps rather suddenly, as well.

Seems like you've done your homework, more than I have, but I'd be interested in hearing back

[bozon]

I'm not talking about snap rolling - that's when one wing stalls before the other. I'm talking about the ability to counter full throttle torque at very low speeds, before stalling.

Bozon

[Sable]

I sometimes wonder about this too.  At high angles of attack approaching a stall a Cessna 172 requires full rudder deflection to keep the nose straight, and it only has 160hp.  A piper Seminole on one engine will generally lose directional control (you have the rudder deflected as far as it will go and the plane keeps yawing away) before it stalls at around 56 knots.  I'd think that 2000hp warbirds would probably be much harder to deal with at low speeds with full power, but then I've never flown one so I can't say for sure.   My guess is that they would still run out of rudder before they ran out of aileron though.  The rudder only has the horizontal stabilizer to use as a lifting surface, while the ailerons essentially use the entire wings.

[GScholz]

Stall speed is still triple digit mph numbers for most of the late war torque monsters. If the plane has very good aileron authority (190s, P-47 etc.) it should be no problem. On other planes however low speed - full throttle would be a problem like on the Spit14 and 109G10 which need full aileron deflection just to counter torque.

[SFRT - Frenchy]

Bozon, you have a couple of hours of flight?  Don't make your instructor ashamed and go back hit the books.
Look under "left turning tendancies", you left out P factor, and Gyro effect.

About those tendancies, a p51 pilot from Chino told me that in athe pony, when you turn right you use right rudder. When you turn left, you use LESS right rudder.  i don't know how true it is I never even came close to fly a P51.

[Sable]

Originally posted by SFRT - Frenchy

About those tendancies, a p51 pilot from Chino told me that in athe pony, when you turn right you use right rudder. When you turn left, you use LESS right rudder.  i don't know how true it is I never even came close to fly a P51.

That sounds pretty reasonable to me.  That's how it works in a small twin when you are flying on one engine.  You need about full rudder to turn into the working engine when at blue line, and just a little less when turning away from it.  Having the operating engine off center really magnifies all of the left turning tendencies (or right turning as is the case with the left engine on the seminole).  I'd have to think a 1700hp merlin would produce at least as much torque etc. as a 160hp lycoming that is 6 feet off center.

[SFRT - Frenchy]

Remember doing a Chandel? Left chandel, right rudder:)

[GScholz]

Originally posted by Sable
That sounds pretty reasonable to me.  That's how it works in a small twin when you are flying on one engine.  You need about full rudder to turn into the working engine when at blue line, and just a little less when turning away from it.  Having the operating engine off center really magnifies all of the left turning tendencies (or right turning as is the case with the left engine on the seminole).  I'd have to think a 1700hp merlin would produce at least as much torque etc. as a 160hp lycoming that is 6 feet off center.

You're mixing forces here. Having an engine off center has nothing to do with torque.

[bozon]

Originally posted by SFRT - Frenchy
Bozon, you have a couple of hours of flight?  Don't make your instructor ashamed and go back hit the books.
Look under "left turning tendancies", you left out P factor, and Gyro effect.
 

I said the roll axis, not yaw

[SFRT - Frenchy]

Doh!