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vikingair

Can't control taxispeed with turboprop a/c

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I have big trouble with controlling my speed, then I taxi my turboprop aircraft. Both the standard King Air 350, and by all other downloaded on the net. The the problem is, the speed increase up to about 25-30 kts, even with the trottle in full idle position.I use a joystick there I can control the engine and the propeller individual. I have no problems with piston engine aircraft with changeable propellers. The 2 controllers for engine and propellers works fine, then I am in the air.There have to be some parameters in the *.air or aircraft.cfg to tweak? I have tried to change some of the parameters, but it doesn't change much.

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Some of these are very sensitive to the "condition" levers. One RW site I found for the Beech King suggests that the engines are started in "low idle" and after the first start, that engine is placed in "high idle" for starting the second engine, then both levers are placed in "low idle". I have seen some conflicts as whether to place the levers in "high idle" for take-off, or leave them in "low idle" at all times, except in certain conditions. At any rate, if you move the levers as close to cut-off as you can, the min idle speed will keep taxi at a decent speed without riding the brakes.scott s..

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When flying a turboprop with turbine engines you have to view your "mixture levers" for the piston engine as "condition levers" for the turbine engine. For ground operations such as taxing have the levers in the mid to low position. This is referred to as "ground idle" in the real world. Before taking off move the levers full forward to what is called the "flight idle" position. They are to remain there for all flight ops but I have moved them to "ground idle" on approach if the airplane had a tendancy not to slow down very well. They should be in "flight idle" for reversing the prop to slow down to save the brakes.

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The FS rendition of the turboprop engine has long standing and well known issues with ground taxi.As noted above, you not only have to keep the throttle idled but the condition lever/ value/ setting also low to be able to taxi at a decent speed.The issue is something very integral to the way the .AIR files in Flight Sim works and not something which can be changed easily.FS uses some basics which go way, way back to before it was MS Flight Simulator to make the .AIR file concept work.It's probably not going to change in the next few versions unless MS throws out everything and restarts from scratch.

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Vikingair:I have one turboprop aircraft (a Beech Starship) that just won't keep the taxi speed down, even with the condition lever adjusted down. I finally had to install Rob Berendregt's ground handling gauges to control the speed, otherwise the taxi speed could get up to 80 knots.You might give it a try if all else fails. The file is rcbgh-32.zip. I don't remember if it's here in the library files or if I got it somewhere else.

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The Majestic Dash 8 solves this problem by using four engines. I don't totally understand it but I gather that it has two phantom engines facing in the opposite direction and they produce thrust when taxiing. The effect is that at low power settings the taxi speed is easily managed using power alone, just like the real thing.

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Flight Simulator to make the .AIR file concept work." OMG! There's SubLogic code still in MSFS?? Say it ain't so! :-smile12 Next you'll start talking about some great airport called Meigs... sheesh. More on-topic: I've found that pulling back the props a bit also helps in ground handling. It takes a bit of experimenting. My DA Cheyenne with the props pulled to about an 80% position and the condition levers on Low seems to be managable. The Aerowrox KingAir I always had to "catch up" with as I was either at a dead stop or off to the races. Like was said, a noted problem with FS turboprops. Mike

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As per advice from 'Yoda' over at Aeroworx, I've found that setting props full forward, condition levers at 200 - 220 ft/lbs, then intermittently applying a little power makes the B200 eminently manageable on the ground.regards,Mark

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Thanks for all you answers and advices, but....I know there is some difficulty in the way FS2004 handle turboprop aircraft. I have been away from making changes to aircraft for a while, and thought there had been new knowledge.Some of the turboprop aircraft is allright to taxi with, but most other are nearly impossible. I have made some experiment in turboprop aircraft with TweakFS. It only change the aircraft.cfg file, and sometime it make it a little bit better, and some other times, it makes things much worse. Therefore I think it is in the *.air file.RegardsVikingair

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