Stopping an engine from starting?

[Guest mgipson]

What is the best way to stop an engine from starting? It's a twin turbine aircraft and I want to stop an engine from starting if all the switches have not been set correctly. Currently I am shutting off the fuel valve but I what to use this to allow fuel to be switched on while the start sequence is running. Is there anything else that can be set that will stop one engine from starting even though the KEY_TOGGLE_STARTER1 is being toggled?Thanks.

[rcbarend 37]

There probably will be other ways as well, but one way is to keep the mixture for that engine forced to zero when not all start conditions are met.Like using events MIXTURE*_LEAN (with *: 1,2,3 or 4)Rob

[taguilo 33]

""Is there anything else that can be set that will stop one engine from starting even though the KEY_TOGGLE_STARTER1 is being toggled?""Unless you are doing a CTL-E autostart, you should stop toggling the starter. Something like:"All Ok for start sequence"if{ toggle_starter1 "all Ok to add fuel" if{ 16384 mixture1_set } }Tom

[Guest mgipson]

Setting the mixture to fully lean sounds like a good idea, I can stop toggling the starter because I want the engine to turn over. The idea is to turn the engine when the start switch is held left or right but not to start if you have not switched on the fuel, ignition etc.

[taguilo 33]

Ah ok. Then Rob's suggestion is the way to go. Before executing the start sequence, you may cut the fuel ( 0 (>K:MIXTURE1_SET) ) and command a "fuel on" ( 16384 (>K:MIXTURE1_SET) ) only when combustion conditions are met.Tom

[Guest mgipson]

I tried this and it works perfectly, thanks guys!

[rcbarend 37]

By the way, don't induce the famous "continuous event" problem here; so test the actual state of the Mixture lever before giving an event to avoid a continous stream of events.Like (when engine start should be blocked):(A:GENERAL ENG1 MIXTURE LEVER POSITION,percent) 1 >if{ 0 (>K:MIXTURE1_SET) }Cheers, Rob

[Rocky 128]

And do you know how to interrupt the engine start if Ctrl-E autostart has been used?I tried to trigger an ENGINE_AUTO_SHUTDOWN event, but it doesn't work everytime.Thanks,Eric

[taguilo 33]

Eric,AFAIT it is not possible to stop the autostart once begun until the first engine is running stable (not even with an AUTO SHUTDOWN event). The starting process seems to be hard coded in a different way than the standard set of starter-fuel mixture control events.Tom

[Rocky 128]

According to the tests I have done, you are 100% right. The problem is that you can catch the autostart event with an "On Event" (or its equivalent in C++), but you can't intercept it. It means you can not abort an engine autostart, unless I missed something...Any clue?Thanks,Eric