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dubravko

Propeller aircrafts landing

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I downloaded King Air 350 from AVSIM library and started flying around with it. In general data about this airplane it says that landing speed is about 115 kntots. When landing at that speed it's kind of hard to stop on the runway without using brekes since props do not have reversers on their engines. So I was wondering how do propeller aircrafts stop when landing? I've also found out that it's easy to stop with smaller props like Cessna, Renegade and Piper because they have smaller landing speed so I can use brekes. It seems a bit strange to use brakes when landing with King Air at 115 knots especially if runway is covered with snow, ice or rain.I wasn't really flying props much with FU3, Beechjet is my primary airplane, but I'm more interested in props now.

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The King Airs are really turboprops but in FU3 the 350 has been based on the propeller model. As it was for MS Flight Simulator until version 2000 Pro we don't have a true turboprop model. This means that a turboprop will have to be based on either of the two available models, namely jet or piston engine propeller aircraft. The choice of either one will entail pros and cons.The FU3 King Air lacks reverse pitch as you have noted. It also lacks beta thrust which is more or less than same. The thing is, turboprops can and will use the propellers for braking and for fast descents into steep valleys when required. However, the FU3 model flies pretty much like a King Air and the only downside (for normal runways) is our lack of reverse pitch for braking. I just use the brakes and pretend I'm using reverse pitch :-)Hans Petter

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I use the fence. That usually stops me. x( Reverse pitch would have been easy to model. I'm surprised the range of pitch angles can't be increased with the flight dynamics editor, but I must admit to complete ignorance (in the area of modifying flight dyanmics I mean).Question: when your engines fail in a single prop, you're supposed to feather the prop for maximum glide distance(*). Now keep it simple for me (I'm from Tasmania, sorry QvdG, I mean I'm from Ulverstone, whoops sorry Chris, well I'm from Sydney, bother, hi Jon) well anyway which way do I push/pull the blue knob to feather the props?I think I'm supposed to push it right in, since that should increase the blade AOA. When it happens (I have the MTBF flags set at about 24 hours) I am usually too busy working out where to hit the ground than experimenting!(*) Maximum Glide Distance: defined technically as two miles short of the nearest airport.RobD.

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Folks,You CAN model reverse pitch with props in FU3. The problems are::-( Slow response speed:-( Lack of a centre or 'zero' detent. This makes prop control impossible near the 'zero' point. :-( You MUST have a manual pitch lever (due to delays in using the keyboard).It DOES work though, I still have a Dash-8 flight model that uses it. Unfortunately, by the time the props respond, you would have been better off just hitting the brakes :-rollI am playing with it in the Saab 340 though, as it's based on the B400 :-waveAs to pulling it or pushing it, just hit & <-> and hold for a few seconds*.*Why do the hand controls in FU3 have an actuation time? Because it's realistic? Well, I'd like to speed them up somewhat, if possible!Rob, if in doubt, it's the direction that DOESN'T make the prop spin :-eekRegards,**************Jonathan Point**************"I'd rather be down here wishing I was up there than up there wishing I was down here"

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Thanks Jon, so I had it 100% wrong (don't nobody say nothing).RobD.

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"*Why do the hand controls in FU3 have an actuation time?Because it's realistic? Well, I'd like to speed them upsomewhat, if possible!"Have you tried speeding up the repeat interval? you can do it like soin your joykeys.cfg for keyboard strokes, from the 'Readme' files ;Making Joybuttons RepeatJoybuttons can made be to repeatedly invoke their bound function as long as a joybutton is held down by adding the _rep modifier to the end of the joykey code name. This is good for things like trim or prop pitch which have a large number of increments.You can set the overall global repeat rate with the config variable joykey_repeat_interval, which is repeat time in seconds. Default value is 0.1.You can set the overall global delay before repeating begins with the config variable joykey_repeat_delay, which is also in seconds. Default value is 0.25.The repeat rate for individual buttons may be scaled by adding _XX after _rep, where XX is between "1" (fastest repeat) and "15" (slowest repeat). "10" is the default repeat rate. For example, with the default values, you could make joybuttons repeat with an interval of of .001 seconds to .15 seconds.The syntax would beshift_kp_+_rep_xx Prop_Increase shift_kp_-_rep_xx Prop_Decrease replace the xx with a repeat value between 1 and 15(Or you could try adding the repeat modifier to your Joy_Devicesection in the main flt3.cfg file if youre using a flight yoke withpitch and mixture controlsFor example "mixture_device 2 8 +rep_xx" I haven't tried this so can't say if it works):-wavePete

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Pete,Yes, I could do it that way, except that it would make actually setting '0' harder...What we actually need is a reversing throttle control (and yes, I know it cannot be done) or, now you got me thinking, a joykey to set the '0' pitch position. Then travelling full forward or reverse wouldn't be so hard.To those of you confused by this, in a normal turboprop (Dash-8/DHC6/Skyvan etc), the throttle levers are also the pitch levers. When you pull them back behind '0', the throttle increases again, but with reversed pitch. In FU3, we will always be stuck with separate pitch and thriottle controls - unless someone has some great ideas. I know for example, that we can link the throttle and pitch controls but you cannot have 'negative' throttle :-(:-waveRegards,**************Jonathan Point**************"I'd rather be down here wishing I was up there than up there wishing I was down here"

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That's why I am looking forward to Daniel's Boeing 717. Reverse thrust in FU3 JETS is second to none ;-)Chris Low.

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Hi Jon, need to make a slight correction here,"To those of you confused by this, in a normal turboprop(Dash-8/DHC6/Skyvan etc), the throttle levers are also thepitch levers."Throttle, or more correctly fuel or power levers, are always fuel or power levers,they don't control prop pitch, the prop governor does"When you pull them back behind '0'" flight idle actually "the throttle increases again,but with reversed pitch." What happens is that there is an interlink activated between the fuel or power lever and the prop governor, it sets an rpm that the engine must remain at (constant speed) and allows reverse pitch to be engaged,whilst at the same time limiting the forward pitch range.The propellor is then said to be operating in the 'beta' range. Because the power lever is below flight idle, the fuel flow is fixed (actually its a set rate dependant on throttle position, ie max reverse is more fuel than ground idle) so to keep the prop at constant speed,the governor moderates the pitch. Because the forward pitch range has been limited, we get reverse in response to more fuelThere,that should cover it....:-wavePete

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Pete,Thanks for that! My version would have spanned 3 pages :-roll I just wanted to simplify it for those that aren't familiar with turbos. Unfortunately, I simplified it to the extent that it appeared wrong to someone that DOES understand...I still get emails asking why the prop RPM on the Dash-8 doesn't change when throttle is increased - and I explained THAT in the manual...Again, in FU3 we are stuck with 2 controls (or 1 + a switch for jets).:-waveRegards,**************Jonathan Point**************"I'd rather be down here wishing I was up there than up there wishing I was down here"

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