The effect of the prop and engine are not only torque Martin. The
airflow (or propwash or slipstream) passing down the fuselage impinges
on the rudder and causes a yawing force. In addition, while the
aircraft is on the ground the torque would cause one tyre to be
compressed more than the other and cause yaw through drag - in the same
direction as the propwash. I fly little Grobs with a right-hand
tractor prop (top blade is always travelling right, viewed from the
cockpit), so I need right rudder on takeoff and on selecting full power
in the air. It has no rudder trim in the cockpit and is trimmed for
100kts, so I need rudder adjustment to maintain balance at any other
speed or power setting than the cruise power setting.
I am not sure if the powerful fighters needed to take off with less
than full power, but I have never heard it mentioned. On the other
hand, as you say an overshoot required very careful handling. A
Mustang pilot (a farmer in Norfolk) told me that it was dangerous to
allow the speed to get below a certain value on the approach since if
he had to overshoot ("go around") it might be easy to forget to limit
the power needed and to roll quickly and uncontrollably. This is that
aircraft, Maurice Hammond is the pilot:
http://www.b.totten.btinternet.co.uk/html/janieframe.htm
A slight correction: all propeller-driven aircraft will _roll_ more
easily in one direction than another; a right-hand tractor aircraft
will roll left more easily. But once you have rolled to your required
angle of bank for a turn, the turn works fine one way or another. The
little Grob that I fly rolls very slowly unless you flick it (virtually
spin it by stalling it and using full rudder) when it becomes fun to
fly aerobatics. But it is only a trainer, a moped of the skies ;-).
Finally, contra-rotating props solved the problems, as contra-rotating
rotors do for helcopters, but there are penalties in weight and
complexity.
Chris
On 10 Apr 2005, at 3:08, mwalters wrote:
snip
> Brian is right that the XVIII was a brute, but boy was it fast. Pilots
> of the
> Griffon spits treated the engine's torque with respect. In fact at
> slow speeds,
> the torque was enough to overcome the controls and the plane would do
> a torque
> roll under full throttle. A lovely situation if you were trying to do
> an
> overshoot!!! The only answer was contra-rotating props, as seen on
> the Seafire
> 47. This had a 2200 hp griffon but no/no torque effect as each prop
> rotated in
> opposing directions.
>
> Martin.
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