Controls

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mace
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Controls

Post by mace » 07 Sep 2006, 21:54

hello
sorry but i can write the next sentence only in german:
das seitenruder sieht ein wenig gebogen, kurvig aus!! ist das normal??

Marcel

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Alex
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Post by Alex » 07 Sep 2006, 21:58

sorry, I can't answer this question :)
I don't understand only one word, was ist seitenruder?

Sorry for my Deutch :)

Alex

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Post by Guest » 07 Sep 2006, 22:05

sitenruder=side oar,rudder

snave
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Post by snave » 07 Sep 2006, 22:12

If I translate correctly, it's about the curvature of the rudder? I'm not sure if it's a model question, or about the flight dynamics? Or does it refer to the elevators droopping at rest?

Because if it does, yes they do!
Simon Evans

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Andrey
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Post by Andrey » 07 Sep 2006, 22:40

Much time takes me understanding this question :)

is this an answer: http://www.airliners.net/open.file/1053192/L/ ?

... or I got something wrong ?

Andrey
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Guest

Post by Guest » 07 Sep 2006, 23:02

yepp,thnaks really much.but why is it like this???

Marcel

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Andrey
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Post by Andrey » 07 Sep 2006, 23:10

I do belive that for gyro-effect compensation... 7.3 liters.. 6 cilynders...

Andrey
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snave
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Post by snave » 07 Sep 2006, 23:11

I don't get the question?

The rudder is the movable surface at the rear that changes the direction the nose of the aircraft is pointing. It moves left or right, and in flight is one of the main control surfaces of any aircraft.

It's sitting like that in the picture because the pilot left it there, or the ground crew moved it there, or maybe the wind blew it there.

The rudder is easily moved and isn't sprung-loaded to return to the centre postion.

Mace, do you have Flight Sim on your computer? If so, try one of the basic lessons with Rod Machado, where he explains how and what the controls of an aircraft do.
Simon Evans

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Knorren
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Lock

Post by Knorren » 07 Sep 2006, 23:21

The siderudder (also elevators and ailerons) are in a locked position on that picture so that no damage will occur during windy conditions. You lock the stick and the pedals with a leather strap down on the floor on the pilots side.

Edit: as Simon said the rudder are not sprung-loaded and has to be locked to prevent damage as I mentioned above.
Regards
/Johan
Proud Pilot of KVZ and LAZ
http://www.f15fk.se
http://www.fcfk.com/fcfk/

S91C
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Post by S91C » 07 Sep 2006, 23:33

Snave and Knorren.....

It isn´t the position of rudder the guys above talking about. It is that (i supose 8) ) the rudder is not symetric. And yes, I guess it is for compensating some of the gyroeffect from the big bigblock 6 cyl heavy mean machine in the nose just as Andrey says, or/and the prop slipstream ...... :D

//Per



"messerscmidt" again........ 8)

snave
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Post by snave » 07 Sep 2006, 23:42

Yeah, even as you wrote that i was about to post something similar.

Anyone want to explain `gyroscopic precession`, `torque reaction` and `turning moment at a distance from the fulcrum` to Mace in German? I don't think he'll get it in English!
Simon Evans

Arne Olav

Post by Arne Olav » 07 Sep 2006, 23:58

It's for compensating the tourque-effect.
The Safir is very touchy regarding the "ball". When ever you change the engine setting, you have to trim, and "kick the ball back on place" with the rudder.

It's a weird feeling to se the SAO in a Flight Simulator-setting.
This model surely will save a Safir-pilot a lot of money on training :)

snave
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Post by snave » 08 Sep 2006, 00:27

Yeah, it's a top-flight flight model! One of the very best!

But the reason the rudder curves from top to bottom, (when looked at from directly behind) is because ABOVE the line of the fuselage the propwash is not striking the tail like it is when it runs along the side of the fuselage. This contributes a varying torsional fulcrum effect as the tail goes further above the centreline - and this would result in differential loading on the rudder up and down its length, trying to twist it off its mounting if the camber wasn't adjusted to compensate for the sideways force.

The `twist` in the shape of the rudder performs a similar function, but for a different reason, to tip washout on the wings.

Like I said, I can't explain that in German!
Simon Evans

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Hakan_Olsson
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Re: Controls

Post by Hakan_Olsson » 08 Sep 2006, 23:18

mace wrote:hello
sorry but i can write the next sentence only in german:
das seitenruder sieht ein wenig gebogen, kurvig aus!! ist das normal??

Marcel
Ich spreche und schreibe deutsch wie ein idiot aber ich fersuche: :D

Ja das ist ganz normal. Es ist ein aerodynamische finess wie kompenziert das "P-faktor".

Håkan

(I hope I havn't insulted anyone or hurt anyones feelings with this feeble attempt)

mace
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Post by mace » 11 Sep 2006, 19:14

DANKE nochmal, aber warum sieht das bei den meisten anderen flugzeugen nicht so aus, die haben das nicht.

Marcel

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Post by DNovet » 12 Sep 2006, 00:24

Marcel...

Tönt vielleicht ein wenig banal...

Aber:
Warum sieht denn eine Cessna nicht aus wie eine Piper?
Und warum sieht eine Piper nicht aus wie eine Cessna?
Eine Cessna heisst Cessna, weil sie wie eine aussieht...

Um den slipstream-effekt des Propellers loszuwerden gibt es verschiedene Möglichkeiten.
Die modernste wäre der Yaw-Damper, welcher jedoch Elektronik benötigt.
Dann wären da noch die Möglichkeit von einer schrägen Anordnung des vertikalen Leitwerks, also dass dies ein bisschen nach links zeigt.
Und dann kann man dies auch noch off-centerline montieren.

Alles in allem dienen diese aerodynamischen Murkse dazu, denn aerodynamischen Luftwirbel, welcher durch die Rotation des Propellers entsteht, entgegen zu wirken.
Damit hast du nicht eine Änderung im Yaw-Moment, wann immer du eine Leistungsänderung durchführst.

Bräuchte jetzt längere aerodynamische Erläuterungen, aber lass dir gesagt sein:
Dieses Seitenruder ist eines der Merkmale der Safir und wird wahrscheinlich heutzutage nimmer gebraucht, da man lieber in der Produktion spart (flaches Seitenruder ist einfach zu fertigen als ein verwundenes, und damit billiger), anstatt aerodynamische Feinheiten zu produzieren.

Gruss,

Daniel

mace
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Post by mace » 12 Sep 2006, 12:02

WOW, danke für deine super antwort, jetzt ist mir alles klar!!!

NOCHAMLS DANKE

Marcel

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