Turboprop-handling

[Guest lou ross]

Maybe the best Turbo-prop is the Dash 8 by Majestic- designed for procedures training by flight crews at Tyrolean Airlines (Airways?). 2 versions available. BTW, prop sync at cruise, auto-feather for take-off because it is quiker to react.

[Guest allcott]

>Thanks for the info, how much drag do these flaps produce?In some aircraft they actually produce nett thrust, not drag. A couple of Steve Smalls flight models have modelled the drag of the cowl flaps by putting cowl flaps to the spoiler key rather than the cowl flap button. Again, I dont think the drag of using these scoops is modelled normally in FS.Allcott

[Guest allcott]

>I may be completely wrong here, but it's not life or death>and I like this discussion..>>I believe I read somewhere that the DC3 has some issues with>the cowl flaps interrupting airlow over the control surfaces.>It's negligable I'm sure, but in certain conditions could be>dangerous. Also, there is some talk amongst the older fellers>that leaving the cowl flaps closed at start-up can actually>make engine warm-up faster. I've heard the arguments against>that too, namely creating too much heat in the cowling and>frying the ignition wiring. I imagine those engine harnesses>are NOT cheap for a Wright radial. Don't forget to keep 'em>closed while parked over time so the birdies won't build nests>in them! And always check 'em with a can of Raid before>start-up. Pesky wasps and hornets!Most radials benefit from a faster warmup to get the oil flowing where it's needed. Even today, I think the Vedeneyev M14P radial (one of the few still in production) recommends coolers closed on startup. But a lot must depend on the amount of heat being generated and the effectiveness of the cowling in channelling hot air and exhaust at low or zero airspeed I guess. The temp gauge in the aircraft typically measures oil temp, cylinder head temp, maybe exhaust gas temp if it's a turbo. These make no account for acute `hotspots` that might develop in a closed cowling on an aircraft idling for any legth of time (bearing in mind MOST aircraft idle for extended lengths of time during warm up anyway). Think about the latent heat generated around a turbocharger that's just idling at 100,000rpm or so and you can imagine why opening the cowl flaps during t/o is a good thing - not only to keep the engine cool during high-power, low IAS situations, but also to dump hot air that may have been trapped inside during the prolonged start-taxi-queue procedures.Allcott

[Guest janpfs]

I just love this hobby! And this forum.You ask a question, and everybody take their time to answer. You just get to know more and more of the "world of flying" Thank you very much.I think I will drop another question then: Larger turboprops, like the Dash 8 and the Dornier 328, doesnt seem to have mixture controls, like the King Air. Why is that? My situation is, I`m building a home-cockpit, not type specific, as I want to fly different aircraft, but something close to the Dash 8. When building the throttle-quadrant, I would`nt have to build the mixture control handles, if the King Air is one of the only turboprops with these.:-)Regards, JP

[Guest allcott]

>I just love this hobby! And this forum.>>You ask a question, and everybody take their time to answer.>You just get to know more and more of the "world of flying">Thank you very much.>>I think I will drop another question then: Larger turboprops,>like the Dash 8 and the Dornier 328, doesnt seem to have>mixture controls, like the King Air. Why is that? >>My situation is, I`m building a home-cockpit, not type>specific, as I want to fly different aircraft, but something>close to the Dash 8. When building the throttle-quadrant, I>would`nt have to build the mixture control handles, if the>King Air is one of the only turboprops with these.:-)>>Regards, JPOK, me again! You might want to do a forum search on Condition Levers in the forum for lots of threads on this very topic over time. In simple terms, they aren't `mixture levers` although they do adjust fuel flow. A turboprop doesn't require mixture control because the fuel/air mixture is far less important than in piston engines where a near-stoichiometric ratio is required for combustion to even take place. A Turboprop is basically a jet engine - pour in fuel, light the blue touchpaper, stand well back, then put a fan on the front!Thing is, turboprop engines make a proportion of their total thrust from jet efflux as well as the whirly bit up front. Add to that the fact that turboprop (and jet) engines produce considerable static thrust at idle, and you have the potential for problems - the King Air will taxi and accelerate at idle thrust with the condition levers at high idle - not good for the life of the brakes or the nerves of the pilot who looks down to check his instruments, looks back and finds he's barrelling down the taxiway at 30 knots! You can control this by retarding the props, but it then becomes an on/off switch.So many turboprops have a way of `choking` the fuel flow just a little to reduce this idle thrust - Low Idle. More sophisticated turboprops have computers controlling that kind of thing so don't need the option. You do NOT adjust the condition levers as climb higher like you would in a piston-engined aircraft, you simply set them to where you need them for ground and/or air operation and Go Fly!Hope this helpsAllcott

[rightseat 277]

"Stoichiometric!" Allcott, you've just said the word of the day! ;-)

[monnie 1]

Marco,Firstthanks for your answer even though I did not ask the question. It was good information for me since I'm thinking about learning to use torbo props. However that is not the reason for my post. I completely understood your response which is pretty significant as I am usually put in the fetal position when it comes to technical stuff. My question relates to your explaination pertaining to the Prop Syncs.Did you verbalize that sound before you typed it and was anyone around when you were doing it???:-) I read your answer, heard the sound in my mind as you described it and verbalized it aloud to set it im my mind. Problem (and I hope you can help me here also.)How do I stop my wife, daughter and 2 dogs from starring at me with their mouths open in amazement? I'm innocent this time.Best regardsJan1,KINDWhen I push the button and it works, I'm happy:-)

[Murmur 3,941]

>My question relates to your explaination pertaining to the>Prop Syncs.>Did you verbalize that sound before you typed it and was>anyone around when you were doing it???:-) I read your answer,>heard the sound in my mind as you described it and verbalized>it aloud to set it im my mind. Problem (and I hope you can>help me here also.)>How do I stop my wife, daughter and 2 dogs from starring at me>with their mouths open in amazement? I'm innocent this time.LOL :D To be honest, I must say I am not the original creator of rrrrRRRRrrrrRRRR