Fixing Roll

[Wolf_Rider]

sorry, I meant "might help" for readers in general not directly for you... my bad


(I'd take a heavier flywheel, than stock, in my daily ride any day... they're so good for storing all that kinetic energy, eh)

[bongodriver]

Originally Posted by Wolf_Rider

sorry, I meant "might help" for readers in general not directly for you... my bad

Ah! OK......my bad too for assuming, I figured we were saying the same thing anyway.

[b101uk]

Originally Posted by Wolf_Rider

its like this:

A helicopter had to have the tail rotor put on it for what reason?

that's right... to prevent the main rotor and the main body (housing the engine) from spinning in opposite direction.

double main rotor 'copters spin in the opposite direction: why?

and there is no prop on the ever popular car anology, when the engine is revved hard causing lurch.

piston drives the cranshaft which turns the prop. the piston moves down bwcause the explosion, which causes the movement because it forces the piston to move down using the block/ head as the base. the engine block is mounted securely to the vehicle, etc, etc, etc

helicopter have main gearbox fixed in the body which turns torque threw 90deg, so the engine has little to do with it with regards to its own flywheel effect as the load from pushing the blades one way is put into the main body by the gearbox case wile the tail rotor counters main body yaw and engine only counters input shaft load and is 90deg out of sync with you example!

If your then talking about vehicles like cars, trucks etc, agene the engine is mostly fixed to the gearbox which has its own mounts and the small amount of rock you get from sharply revving the engine when there is no load is minuscule in comparison to the amount of torque from the gearbox output shaft which will in fact twist the gearbox case and thus vehicle body/chassis the opposite way wile the engine that is rigidly fixed to it is only countering a smaller input shaft load.

Also with gearbox in the equation with lower output ratios resulting in increased output torque (like trucks, helicopter, turbo-props, etc etc etc) if you input say 500NM and get out 1500NM then ware dose the difference in output torque have an effect and ultimately go, via the gearbox case into the rest of the vehicle by any chance wile the engine is only countering a smaller input shaft load.
.

So forget the engine we are only interested in ware the force from pushing a prop one way ultimately ends up!

Originally Posted by Wolf_Rider

basic law of motion... "For every action there is an equal and opposite reaction"

http://www.aerospaceweb.org/question...s/q0015a.shtml

might help/ might not

you are 19 post behind

The effects of gearbox and high load and a vehicle twisting in the opposite direction to its propshaft

http://www.youtube.com/watch?v=pUVEH7AoEnw

[Wolf_Rider]

right then... well you get the picture of how torque rolls the plane in the opposite direction to the prop rotation

fixed mount - not much roll

no mount - a lot of roll

revv your (car) engine in neutral and watch what happens

[jimbop]

Originally Posted by Space Communist

Generally if you trim the rudder enough to completely counter-act torque you will end up side-slipping through the air. In real life the pilots wouldn't have noticed it as much as we do since there isn't nearly as much of a centering force on the stick. That is to say, the amount of left stick you would have to give it to counteract the torque wouldn't feel much different than holding the stick dead center. After holding it for a long time that would just seem like center to you. At least, this has been my experience since removing the centering spring on my stick.

Cable ties on your joystick spring helps wonders. Great on my x52 pro!

[Doc_uk]

Yea it might well do.
But, most flight sims of today, have a option for this, its called easyflight control
it just takes away most of the hard work

[jimbop]

Originally Posted by Doc_uk

Yea it might well do.
But, most flight sims of today, have a option for this, its called easyflight control
it just takes away most of the hard work

So you're talking about this happening when in an arcade-type mode? Surprising that it isn't level flight for that.

[b101uk]

Originally Posted by Wolf_Rider

right then... well you get the picture of how torque rolls the plane in the opposite direction to the prop rotation

fixed mount - not much roll

no mount - a lot of roll

revv your (car) engine in neutral and watch what happens

I have long understood torque since I was a child some 33 years ago growing up around large machinery, lorries and aircraft some of which were for air racing and that was some time before my posts in this thread.

Now I have razed the point about gearbox, I have razed the point about lower gearing and you keep banging on about the “engine“ in spite of the hints, the prop in spitfires turns clockwise, there is a reduction gearbox on the front of the engine, the engine crank and flywheel turn anticlockwise, because the reduction box reduces the speed of the prop relative to the crank torque multiplication takes place therefore the forces that want to push the “engine block” clockwise under load CAN NEVER MATCH the MUCH BIGGER forces on the gearbox pushing anticlockwise as its trying to turn the prop under load clockwise, hence why e.g. the spitfire/hurricane when at low speed want to dip the left wing if rpm is sharply ramped up - its NOT “engine“ it’s the gearbox vs. prop.

Now go back and look at the video I posted, that is a clockwise turning engine in a chassis being twisted clockwise because the gearbox output shaft is turning anticlockwise which is totally opposite to the “rocking” the engine would do if you merely sharply revved it up in neutral agenised the mere weigh of the flywheels resistance to being accelerated or if under full load its self feeding in to the gear box its rigidly mounted to.

so as i said:

forget the engine we are only interested in ware the force from pushing a prop one way ultimately ends up!

[BlackbusheFlyer]

I agree with the principal that adverse yaw/roll should exist within the sim however I can not help but feel it is applied in too linear a fashion. Test flight on Spitfire at 67% throttle, 2200 RPM no trim, you need a boot full of right rudder to counteract yaw and about 10-20 degree of left aileron to balance the aircraft. Apply rudder trim to remove skid and still require a 10-20 degree aileron deflection to counter roll.

This makes sense at high RPM/power settings but not at cruise power. No real life aircraft I have flown is rigged where you need substantial cross control to maintain straight and level at cruise.

Personally I think the torque effect curve needs looking at.

There are written accounts of spitfires trimmed to fly hands off (Wingleader by J.E.Johnson for one). In CoD at the moment that is just not possible, you can not remove the need to hold aileron no matter what power setting and to me that is not quite right. Something like a pitts special which is extremely twitchy and a real split arsed aircraft will cruise along quite happily with the lightest touches.

[bongodriver]

Originally Posted by BlackbusheFlyer

I agree with the principal that adverse yaw/roll should exist within the sim however I can not help but feel it is applied in too linear a fashion. Test flight on Spitfire at 67% throttle, 2200 RPM no trim, you need a boot full of right rudder to counteract yaw and about 10-20 degree of left aileron to balance the aircraft. Apply rudder trim to remove skid and still require a 10-20 degree aileron deflection to counter roll.

This makes sense at high RPM/power settings but not at cruise power. No real life aircraft I have flown is rigged where you need substantial cross control to maintain straight and level at cruise.

Personally I think the torque effect curve needs looking at.

There are written accounts of spitfires trimmed to fly hands off (Wingleader by J.E.Johnson for one). In CoD at the moment that is just not possible, you can not remove the need to hold aileron no matter what power setting and to me that is not quite right.

Neither of us have time on a spitfire, and I'm not sure what time you have on vintage, but the stearman I fly has a 'huge' prop with a 220hp radial driving it, it is fairly torque'y, I think a 1,000hp merlin driving a 10' prop even at cruise will produce lots of torque and even more gyroscopic effect, without aileron trim I don't see how an aircraft can be hands off and in balance.