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Orlaam

Mystery instrument

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I bet Geoff can answer this question:What is this instrument's purpose, and how do I use it?http://forums.avsim.net/user_files/187666.jpgIt seems to be telling me some vital information about the relationship between my two engines (like, maybe that they aren't synchronized? total guess.)Thanks in advance,

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Propeller Sync for multi-engine prop aircraft. How to use: Depends on FS aircraft. Some let you simply click on it with the mouse. Others don't...you may have to use a keyboard combination.

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The gauge is:Beech_Baron!Prop Sync SpinnerIt's programming is:(A : Prop2 RPM,RPM) (A : Prop1 RPM,RPM) - (*get difference between props*) 0.01 * (*100 rpm -> 1 rpm*) 18 / (*18 frames per sec*) 360 * dgrd (*convert rpm to radian/sec*) (G:var1) + (*add to accumulator*) rnor (*normilze*) d (>G:var1) (*update accumulator*)It's failure is it will freeze if System_Electrical failsWhat does it do - from a description of the King Air panel:Next to the prop sync button is a rotating indicator, which is an indication of how well the prop sync is working. If it's spinning wildly, it means the synchronizer isn't working. If it's not spinning at all, it means both props are spinning at the same RPM. FS default mode makes it very easy to keep props in sync - too easy.For real-world pilots of multi-engine aircraft - keeping the props turning at the same RPM is very important.

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Excellent,I agree that it seems too easy to keep the props in sync. In fact, I couldn't get them to unsync without purposely doing it. That's sort of how I figured out what that instrument was.As long as I have an expert on the line, maybe you could answer a question I've had for some time about mixture.Which instrument on the panel (say in this Beech Baron) indicates to me that I need to adjust the air/gas mixture? Is there one at all? Or am I just supposed to have this knowledge in general?Thanks in advance Reg!

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That's the way I do it with twin engine boats."Ears".Lots of fancy sychronizer gauges available for people that like all the toys.Ears work best.Ron

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Hi,>> Which instrument on the panel (say in this Beech Baron) indicates to me that I need to adjust the air/gas mixture? Is there one at all? Or am I just supposed to have this knowledge in general?There are procedures specific to the aircraft, but generally speaking, there are two ways:Using EGT:* Lean off the engine until you reach peak EGT, then push the mixture forward again through the peak EGT point so you're on the rich side.No EGT:* Listen to the engine note whilst watching RPM, and gently ease the mixture back until the RPM and/or the engine note peaks and drops again, then ease the mixture towards rich again, on the rich side of peak RPM/engine note.That's it in a nutshell. The reason you adjust mixture is because as you climb, the air gets rarer, and relatively, more fuel is entering the engine, so by pulling the mixture back, you reduce the flow of fuel to the engine, to keep the oxygen/fuel mixture reasonably constant (about 14.8:1).As you climb, just keep a check on EGT or engine note, and just gently ease the mixture back to keep peak RPM or note (but stay on the rich side, as above).When descending, do the opposite, but remain on the slightly rich side.When landing at a high altitude airport, I suggest making mixture adjustments on downwind, then again as you descend on the glide, noting that as you descend, the mixture will LEAN, so you PUSH, ensuring you have as close to optimum mixture setting as possible in the event of a go-around.Summary:* Stay on the rich side of peak EGT, RPM and/or engine note* During climb: PULL* During descent: PUSHBest regards,Robin.

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One of the other ways we lean is to use one of these:http://forums.avsim.net/user_files/187674.jpgDial in the parameters (desired horsepower, o.a.t. opposite pressure altitude)-then read your expected fuel flow , and set on the fuel pressure indicator . http://forums.avsim.net/user_files/187675.jpgNote the instruction on the fuel flow indicator-there are green percentages on the lower side-you can also use that to set your power setting e.g. 65%-and the lower edge of the sector is normal-lean and the upper edge best power.http://forums.avsim.net/user_files/187676.jpgThen there is the egt...So normally-when I get to cruise and lazy I'll pull back the mixture and to the percentage on the fuel pressure-while watching the egt and determine the sweet spot. If not lazy-I'll pull out the whizz wheel and verify what it says is pretty close to what I have...Leaning is a mysterious art though and everyone has their own way... :-lolhttp://www.mediafire.com/imgbnc.php/1b5baf...b9f427f694g.jpgMy blog:http://geofageofa.spaces.live.com/

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That's basically how I've been doing it ... just listening to the tone of the engines really, and leaning the mixture down until I hear what sounds like a normal engine rev sound.Thanks for all the advice guys!

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It can get complicated it seems. I love to keep it as real as possible, but in terms of leaning in the sim I usually just lean 20 degrees rich of peak EGT in most planes, unless otherwise stated in the documentation. I try to simulate things as best I can, but considering most planes in the sim can't be 100% realistic and therefore don't have all engine parameters modelled, I make do for now. Plus, I'll probably never get to fly in real life, so I'm balancing fun with realism.

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