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Blood_Hawk23
September 20th, 2014, 03:28
Is there away to add the engine torque from the rotary engines?

I'm working on the Sopwith Camel's air and cfg and want to try to have it so it can snap turn using the engine torgue. This is for CFS2 so I do realize the limitations.

Has anyone ever tried to do this?

If anyone has any ideas let me know.

Till Later,
John

Dev One
September 20th, 2014, 03:51
My initial guess would be to increase the prop MoI, but I only work in FS9/FSX so dont know how CFS reacts.
Keith

Rami
September 20th, 2014, 04:43
Is there away to add the engine torque from the rotary engines?

John,

Try having Fat Albert hanging from the bracing wires. "Hey, hey, hey...which way we turning, dawg?" :biggrin-new:

Blood_Hawk23
September 20th, 2014, 12:52
My initial guess would be to increase the prop MoI, but I only work in FS9/FSX so dont know how CFS reacts.
Keith

Dev One,

Thank you I'll try adjusting it.

here are the current specs.

propeller_moi= 12.697

FSedit suggests a value of 13

I have increased it to 18 with some effect but not much. Now I know that it was the actually the throttle controls (or lack of) that would make it snap turn. didn't it want to roll one way when the mags were off and the other when turned on. Or something like that.

how high should I go. I was thinking that 20-23 would give more of a result. I'll have to test it.

Rami,

Wouldn't an elephant have the same effect.

Dev One
September 20th, 2014, 23:43
BH, I only suggested upping the MoI because as you are aware the engine as well as the prop rotate, FSEdit would probably not realise this, so you might even have to raise it to 50! Just a guess.
Not sure though how FS itself will react to switching mags on & Off although there is a curve in the .air file (table 509) that controls the speed of rundown & also I think in the .cfg file the min throttle limit can have an effect.
Good luck - keep trying.

BTW are you using FSX or FS9? & which model?

Keith

Blood_Hawk23
September 21st, 2014, 08:21
BH, I only suggested upping the MoI because as you are aware the engine as well as the prop rotate, FSEdit would probably not realise this, so you might even have to raise it to 50! Just a guess.
Not sure though how FS itself will react to switching mags on & Off although there is a curve in the .air file (table 509) that controls the speed of rundown & also I think in the .cfg file the min throttle limit can have an effect.
Good luck - keep trying.

BTW are you using FSX or FS9? & which model?

Keith

I'm using CFS2. Its the Sopwith Camel from the Aerocrates. I'm just playing with it. more or less.

I'm trying to get some of the Gyro effect from the engine torque. Mostly to see if I can.

As far as the mags go, It would not work as intended. the engine would just shut off. Though maybe some thing in the throttle curve could be used. I don't know. I believe it was the sudden on and off of power that gave the Camel the ability to do the snap turn. I also think its why so many pilots died learning to fly it.

Did all of the Sopwith ACs use the same controls for the engine? I'm going to have to read up on it more.

Thank You Keith. I'll keep working on it and let you know what happens.

Dev One
September 21st, 2014, 10:38
I've not looked in great detail, but I have downloaded Classic Wings Camel, but its for FSX/P3D. Very interesting to fly. IIRC they have developed a switch to blip the engine, because as you know Gnome rotary's (& other rotary's) of those days were either flat out or not at all, & the art of flying them was to blip the cut out correctly & to counteract the resulting change of torque that ensued.
I must try it again......Having changed computers I need to reload it.
Keith

Bradburger
September 21st, 2014, 16:50
I can't remember if they are in the CFS2 Aircraft.cfg, but in FS9 & 10, there is a 'torque_on_roll =' scalar under the [flight_tuning] section. This will up the torque (opposite rolling effect to the direction of engine/propeller rotation). Depending on how well the aircraft you are modifying is set up as regards its contact points and weight distribution, you should notice this rolling effect increase when you up the scalar, especially when opening up the power on the ground.

But for the Camel, the other scalars you will need to adjust to get the desired gyro effects (that's if they are also in the CFS2 Aircraft.cfg) are 'gyro_precession_on_roll =' \\no longer used in FSX apparently\\, and 'gyro_precession_on_yaw =' to replicate the effect of the rotary engine. (FS9 & 10 also has a 'gyro_precession_on_pitch =' scalar was well).

I did an FM for the old FS9 David Erckhart Camel using the Flight Model Workbook, and these values needed to be adjusted to get the correct behavior for the gyro and torque effects that are present on rotary powered machines.

Interesting Dev One should mention the prop MOI, and it's a good suggestion to try.

However, from my own tests, whilst not affecting the torque (rolling), I note that increasing it did (on say, a P-51 with an MOI well over 100), have a noticeable effect on the gyro effects of the propeller, especially if the [flight_tuning] gyro effect scalers were increased.

The downside of raising the MOI of the prop is that it will then take longer to slow down, and a small wooden prop as fitted to the Camel, which has a low MOI, it stops pretty quickly!

Hope this helps.

Cheers

Paul

fliger747
September 23rd, 2014, 08:50
The above MOI comments are probably the right track and are what I would suggest. However don't ignore the airframe charchteristics! Reducing the aircraft roll MOI may help. Also remember that FS does not model biplane wings, but uses a larger single wing, make sure that a larger span is not used to achieve the requisite wing area. Also placing the position of the engine/prop might make some difference.

Good luck! Tom