Carb Heat

[N08RA]

I've probably missed it, but I've looked everywhere and can't find an setting to allow me to use a spare joystick button (CH yoke) to control the Carb Heat in the A2A Piper Cub. Any suggestions to put me out of my misery?

[Pete Dowson]

I've probably missed it, but I've looked everywhere and can't find an setting to allow me to use a spare joystick button (CH yoke) to control the Carb Heat in the A2A Piper Cub. Any suggestions to put me out of my misery?

Does the A2A Piper Club use the default FS carb heat simulation? If so it'll be one of the FS controls for engine anti-ice. There are several: Anti ice on, Anti ice off, Anti ice toggle, and separate ones for each engine (Anti ice toggle engN where N = 1 to 4).

If the panel uses the standard FS controls you can find out which by enabling Event logging in FSUIPC, operating the switch on the panel, and looking in the log.

Regards

Pete

[N08RA]

Thanks Pete, problem solved. I was looking for an offset called 'Carb heat' or something similar and never thought that something as sophisticated sounding as 'Anti Ice' might have a part to play in the life of a simple Cub. I've now mapped the carb heat control - a cable pull-push at the side of the cockpit - to the Mixture axis which is better than using the mouse or keyboard.

I've also tried to map the Fuel cut-off to the spare Prop Pitch axis, but I suspect it only speaks to the Accusim module as it doesn't immediately cut the engine but allows the fuel in the pipeline to run out first. It doesn't send anything to the log.

Thanks again! Happy landings :P

[Pete Dowson]

I've also tried to map the Fuel cut-off to the spare Prop Pitch axis, but I suspect it only speaks to the Accusim module as it doesn't immediately cut the engine but allows the fuel in the pipeline to run out first. It doesn't send anything to the log.

What "fuel cut-off" do you mean? Normally, with any prop aircraft, you cut the engine by reducing the mixture control to full lean. The fuel tank selection valve is turned to "off" after the engine quits. This is a safety precaution -- if you do it the other way, whilst the engine might suck some of the fuel out of the pipe line after the valve is off, it cannot take it all out, and that leaves a dangerous situation where the engine could start up just if the prop is moved.

Regards

Pete

[N08RA]

I've also tried to map the Fuel cut-off to the spare Prop Pitch axis, but I suspect it only speaks to the Accusim module as it doesn't immediately cut the engine but allows the fuel in the pipeline to run out first. It doesn't send anything to the log.

What "fuel cut-off" do you mean? Normally, with any prop aircraft, you cut the engine by reducing the mixture control to full lean. The fuel tank selection valve is turned to "off" after the engine quits. This is a safety precaution -- if you do it the other way, whilst the engine might suck some of the fuel out of the pipe line after the valve is off, it cannot take it all out, and that leaves a dangerous situation where the engine could start up just if the prop is moved.

Regards

Pete

The Cub is apparently different, Pete (according to A2A, I have no real world experience of the Cub). There is no mixture control, so the engine is normally shut-down by switching off the magnetos. The Accusim module will allow the engine to run for a few moments if the fuel is shut-off, simulating the burning of the fuel in the carburetor. That, I guess, is why operating the fuel cut-off valve doesn't get noticed by FSUIPC.

Regards,

Norman

[Pete Dowson]

The Cub is apparently different, Pete (according to A2A, I have no real world experience of the Cub). There is no mixture control, so the engine is normally shut-down by switching off the magnetos.

Ah, I see. I didn't know that.

Regards

Pete

[N08RA]

Ok, I've made a new discovery from the A2A forum - the 'fuel cut-off' operates via the MIXTURE RICH and MIXTURE LEAN variables. So I've mapped that to my remaining axis (prop pitch isn't used on the cub) and it works perfectly, the cub's engine quitting after about a minute on an idling throttle. I'm not sure why I wasn't seeing that in the FSUIPC log :(

[Pete Dowson]

Ok, I've made a new discovery from the A2A forum - the 'fuel cut-off' operates via the MIXTURE RICH and MIXTURE LEAN variables.

Right -- that's what I would have thought.

Regards

Pete