Brian et al:
This is going to really be off topic. So apologies to all those out there in
Zuikoland who don't get turned on by planes and warbirds especially.
As a non-pilot, here is what I understand about torque and propellor planes - in
this case the Spitfire. The later Griffon engined versions had much more power
(1800 -2200 hp depending on version) than the merlin engined ones (1000 - 1600
IIRC). The engines (and props) rotated in different directions. The Griffon
engines were getting close to delivering more power than the airframe could
handle, especially at low airspeeds (eg, take off) when the control surfaces are
less effective. Once airborne, the rudder could be trimmed so that the plane
would fly straight without continual pressure on the rudder pedals (an Bf 109,
on the other hand, had no rudder trim and the pilot had to apply rudder pressure
throughout flight). Another thing to remember is that all control surfaces were
manual - no servo assist here, and forces were related to speed, design and
gearing. Ailerons were notorious for stiffing up at speed, and roll rates
dropped significantly as airspeed went up. Some planes were better than others.
The Spitfire was OK, though others, notably the FW190, had better role rates.
All single engined prop planes will turn more easily in the direction of prop
rotation. Pilots learned to live with it. Twins should not have this problem.
However, it depends. The P-38 Lightning had handed engines (they rotated in
different directions). The Mossie generally had both engines rotating in the
same direction, though the later marks had handed Merlins (again IIRC). It was
really a question of gearing the prop drive accordingly (I never understood why
Supermarine/RR didn't either design the Griffon to rotate the same direction as
the Merlin, or gear the prop accordingly). However, planes of the size of the
Mossie had much larger airframes and control surfaces, so would have been better
able to control prop torque.
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.
Fernando Gonzalez Gentile wrote:
> on 9/04/2005 00:10, Brian Swale at bj@xxxxxxxxxxxxxxx, wrote:
>
> > So, if we are invaded, we will all have to become guerillas
>
> Supposing the noun 'guerrilla' has an Spanish etymology, Brian; correct
> spelling is done with a double 'r' :^)
> How many times did I double (or missed to double) an 'n', 's' or 'p' so far,
> trying to write in English?
>
> Joking a little on a serious issue. Too late to be awake this Friday
> night... - no surprise pronouncing 'gorillas': is there an essential
> difference?
>
> Regards,
>
> Fernando.
>
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