Throttle synchronization

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Throttle synchronization

Postby snippyfsxer » Thu Jan 14, 2010 9:24 am

My Saitek throttle quadrants seem to be wearing out and I have to recalibrate them yet again.
Last edited by snippyfsxer on Thu Jan 14, 2010 9:26 am, edited 1 time in total.
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Re: Throttle synchronization

Postby DaveSims » Thu Jan 14, 2010 10:19 am

In a real multi engine aircraft, the throttles are often out of sync, mainly because of differences between the two engines.  No two engines, even brand new, perform exactly the same.  One might have an ounce or two more power, might respond a little differently.  As the airplane ages, one engine may wear differently or even be replaced sooner leaving different aged engines on a single aircraft.  Usually the differences are minute, but in cruise it is common to tweak one throttle or one prop lever to try to balance the engines.
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Re: Throttle synchronization

Postby C » Thu Jan 14, 2010 10:29 am

[quote]
In the old days, like piston propliners and earlier jets like the 707, how did it work?
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Re: Throttle synchronization

Postby Fozzer » Thu Jan 14, 2010 10:40 am

Talking about synchronising the Throttles...

I always notice on my Default Beech Baron 58, that even with the Sync Toggle Switch on, the twin engines sound as though they are hunting, slightly out of sync with each other during the cruise.

(Both the Throttles are set to move together, under the control of the Joystick Throttle Lever)

Would slightly maladjusted manual Prop Control Levers aggravate  the problem?

Is the Sim programmed to allow the engine Sync Switch to work as intended?

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Re: Throttle synchronization

Postby C » Thu Jan 14, 2010 3:21 pm

I always notice on my Default Beech Baron 58, that even with the Sync Toggle Switch on, the twin engines sound as though they are hunting, slightly out of sync with each other during the cruise.


They obviously recorded the sound in a unsynched aircraft! ;D
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Re: Throttle synchronization

Postby BSW727 » Thu Jan 14, 2010 7:29 pm

The pilots set the power for takeoff and the engineer would reach forward and tweak the throttle for precise power before 80 KIAS in the 727.
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Re: Throttle synchronization

Postby olderndirt » Thu Jan 14, 2010 9:28 pm

This seems to cover the original question.
[img]http://www.simviation.com/yabbuploads/oldrt18.jpg
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Re: Throttle synchronization

Postby snippyfsxer » Thu Jan 14, 2010 11:39 pm

[quote]This seems to cover the original question.
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Re: Throttle synchronization

Postby Fozzer » Fri Jan 15, 2010 4:30 am

..I've just remembered that the Default Beechcraft King Air 350 Turboprop is fitted with a Synchroniser Push button and Indicator (a revolving propeller) on the instrument Panel.

Once both propellers, Throttle and Prop RPM, are fully synchronised by adjusting the Levers, the propeller indicator stops revolving, and the button is then engaged, both engines are then in Sync with each other.

Note the recommendation for take-off and landing...>>>

http://en.wikipedia.org/wiki/Propeller_synchronization
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Re: Throttle synchronization

Postby Hagar » Fri Jan 15, 2010 4:41 am

I must fit the two devices, (Button and Indicator), in my Beechcraft Piston Prop Twins to prevent the annoying engine "hunting" during the cruise!... :)...!

I'm not convinced that FS is quite that realistic Paul. :-/

C is probably right about the sound.
They obviously recorded the sound in a unsynched aircraft! ;D
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Re: Throttle synchronization

Postby Fozzer » Fri Jan 15, 2010 5:14 am

I must fit the two devices, (Button and Indicator), in my Beechcraft Piston Prop Twins to prevent the annoying engine "hunting" during the cruise!... :)...!

I'm not convinced that FS is quite that realistic Paul. :-/

C is probably right about the sound.
They obviously recorded the sound in a unsynched aircraft! ;D


I've just given it a try, and it certainly works with the Turboprop Twins.
The engines sound out-of balance until all the levers are correctly set, then when the Indicator stops revolving and the Sync Button is pressed, both engines operate in perfect Sync with each other in the cruise... :)...!
Any further change in the lever positions and the engines require re-synchronising again.
It seem to work OK in the Turboprop, with its Turbine+Prop Engines...
Whether it is as effective in the Piston Prop Twins I have yet to discover, with their default Sound recording... ::)...!

...further experimentation required... ;)...!

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...Hunting has been banned in England!.... ;)...!

.... ;D....!
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Re: Throttle synchronization

Postby beaky » Fri Jan 15, 2010 11:14 pm

I must fit the two devices, (Button and Indicator), in my Beechcraft Piston Prop Twins to prevent the annoying engine "hunting" during the cruise!... :)...!

I'm not convinced that FS is quite that realistic Paul. :-/

C is probably right about the sound.
They obviously recorded the sound in a unsynched aircraft! ;D


I know that some multi-engine twin models use a single engine sound file, and it is duplicated based on the number of engines specified. So, while FS is not perfectly realistic in this regard, it does simulate out-of-sync pretty well.  Just take a twin up some time and pull the throttle back on one engine ; you will see what I mean.
I think the amount of realism depends on the number of sound files for different power settings, and how smoothly they can be blended together.
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