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Guest Mathias

Engines overrevving at startup

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Helloi experience some strange behaviours with one of my turboprop planes.When starting the engines (ctrl+e) they rev up to their maximum rpm before settling down to more normal figures.Q: Is there a part of the aircraft.cfg or mdl that addresses the engine behaviour at startup? It can't be a problem with joystick settings as this phenomena only appears with this particular model.Until now I assumed that FS9 would handle the prop-spin direction of ME prop configurations automatically as OPPOSED turning !Therefore the tendency of this plane to veer to port (left) when throttling up at takeoff and when applying reverse-thrust keeps me puzzled !Q: Is there a way to define the direction of each prop manually or if not, where else would the problem be originated?ATM the plane behaves just like it was equipped with engines turning the same direction(clockwise)TIACarsten

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Hello I have recently joined the site and i was wondering if you could help me on a few basice things. i was wondering how you post a message and also how you download cockpits and put them in to the correct place if you could mainly tell me how to install a cockpit that would be grate write back as soon as possible please thanks very much 13oro

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The high overrevving at turboprop startup also has me stumped - would also like to gain more knowledge on how this behaviour can be combatted.As to counter-rotating props in multiple engined or rather -propellered planes add the appropriate version of the following line to the aircraft.cfg's [propeller] section:rotation=1,1,-1,-1This example would mean engines 1 and 2 have clockwise- rotating props and engines 3 and 4 have counter-clockwise rotating props. Putting 0 in there apparently stops the prop from rotating altogether - whatever purpose that could have...This is taken from Ron Freimuth's commented aircraft.cfg, but can also be seen in the aircraft.cfg of the default Wright Flyer.

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Thanks a lot Mathias,got the veering tendency stopped - makes for less smell of peanuts when applying reverse LOLThe overreevving part really puzzles me......I tried looking at different aspects in the "engine/prop department"but it still makes no sense to me. Maybe one of the cfg-gurus has an idea ;)RegardsCarsten

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>Thanks a lot Mathias,>>got the veering tendency stopped - makes for less smell of>peanuts when applying reverse LOL>>The overreevving part really puzzles me......>I tried looking at different aspects in the "engine/prop>department">but it still makes no sense to me. >>Maybe one of the cfg-gurus has an idea ;)>>Regards>Carsten(Hopefully I don't get trashed on this)The over revving problem you are having is actually a common problem with alot of turbine based engines. When I'm working on FDE's the first thing I do is set up the turbine tables in the air file. There is one table that basically controls the fuel going into the engine (I'm keeping this simple because it is actually a complicated process) based on the air being fed in and it also has other purposes as well. By altering this table you can control how an engine spools up to idle, and even how fast it responds to throttle inputs.For example, the DC10 CF6 engine takes about 30 seconds to get to idle after ignition at 20% N2 in real life, and I have been able to do that in the air file, no more surges at startup ;).Its in the 1500 series tables in the air file, and is applicable to turbo props as well.Frit

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>Its in the 1500 series tables in the air file, and is>applicable to turbo props as well.>>FritThanks for the hint, will look into this more carefully then! Maybe it will even allow me to fix the rediculously low idle fuel consumption of my virtual PT6A-110...> (Hopefully I don't get trashed on this)No fears, I am a proud member of the Philippine Flightsimmers Group (PFSG) were we tend to get along a lot better than appears to be the case here in certain instances :)

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Frit, would you care to elaborate a little on which table exactly you are talking about?I have looked into section 1500 often and find the graphs quite nice to look at, but could not until now understand what exactly it is that they do or simulate. And the tables are so complex I strongly assume it is quite easy to completely wreck my air file ?:9 1503...1508Somewhere in there I assume you are talking about?

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