HELP WANTED ON PROPS

[Guest]

Does anyone know how to modify the aircraft.cfg file of a twin prop aircraft to make the props contra rotate?Any help would be greatly appreciated

[Guest PhLem]

Prop rotation is configured in the mdl file. So nothing in the cfg file will be able to change that. It is the designer who incorporates this when animating the props.Udo.:-wave

[Guest]

Well that shot that idea down in flames.... But thanks for the info...Cheers//Tonni

[Guest InBetween]

Here is some info from the aircraft cfg. of the CFS2 P-38 Lightning:[propeller]thrust_scalar=1.0rotation=-1,1 //Engine 1,2,3,... Rotation direction. 1 = CW, -1 = CCWpropeller_type=0propeller_diameter=11.500000propeller_blades=3This AC has counter-rotating props, they can be changed graphically;don't know if the change is aerodynamic?Edit: This is the "Propeller" section.JR

[Guest PhLem]

I believe the change in the aircraft.cfg file is aerodynamically, not graphically. In the cfg you tell the program that you have counter rotating props, so it can calculate the affects for this accordingly. When you have all props rotating the same direction, this will cause a momentum in yaw when you apply power. This momentum is small or almost zero when the props are both rotating in a different direction.Udo.:-wave

[Guest bones]

I've used this CFS command quite successfully.On a single engined aircraft (let's say the C182) the prop rotates clockwise (as seen by the pilot) and the aircraft will swing to the left on take off from engine torque.If you add the line rotation=-1 to the prop section everything reverses. Prop goes round the other way and the aircraft swings to the right. In other words the command overrides the performance data and also the MDL data. The only thing that doesn't change is the visual prop so on the C182 the prop is actually going round backwards (the blades are still unchanged).For a twin the rotation command runs from left to right and you can have rotation=-1,1 for the left engine going round in reverse or use rotation=1,-1 for the right engine. I'm trying to remember which engine on the PA31 goes round the "wrong" way..A lot of the early British aircraft had engines going round in reverse - the early Spitfires, the Gipsy Moth engined aircraft etc.

[Guest]

Thanks for the help...I'm working on a new .cfg file for the Baron with an engine upgrade to turbocharged 375hp units... I know that some of these upgrades use contra rotating props in real life, so I wanted to add this as well...Right now without the contra rotating props, apply 80% power on take off, and she's miles off the runway before you can straighten her up again.. apart from that she handles much like the upgraded one I go on business trips in sometimes (real world).... Great improvement...Cheers//Tonni