Adverse Yaw

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Roger
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Adverse Yaw

Unread post by Roger » Tue Mar 10, 2009 4:43 pm

When doing a test flight with a few mates a while back on a competitor product, it was mentioned that the Cheetah suffers adverse yaw more so than other offerings in it's class.

How true is this, or was it mere 'pub' talk that often becomes factual? :?:
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Re: Adverse Yaw

Unread post by rod smith » Tue Mar 10, 2009 6:26 pm

I haven't yet done my type conversion, but I guess that I am going to have to learn all over again how to use the rudders. I have become a bit complacent on this score, having flown mainly the Mooney and the Seneca for the last fifteen years.The ball seldom goes out of the middle. Let's see how it goes.

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Re: Adverse Yaw

Unread post by Bearcat » Tue Mar 10, 2009 6:36 pm

rod smith wrote:I haven't yet done my type conversion, but I guess that I am going to have to learn all over again how to use the rudders. I have become a bit complacent on this score, having flown mainly the Mooney and the Seneca for the last fifteen years.The ball seldom goes out of the middle. Let's see how it goes.

Rod Smith
Rod, which Cheetah do you now own ...and where is it based?
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Re: Adverse Yaw

Unread post by rod smith » Tue Mar 10, 2009 6:46 pm

B, Hi

I am sure that you would have it somewhere in your archive. It is the bright orange one (day-glo orange). Reg is ZU-ETC.

I am in a partnership arrangement with my two brothers in law, both of whom you have met a few times. The a/c is at Springs, now, having been flown across from Rhino Park on Saturday. I am not getting out of the Mooney; this is just an attempt to create some cheap flying and thus to fly more regularly than I have been doing.

Rod
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Re: Adverse Yaw

Unread post by Flybynite » Tue Mar 10, 2009 8:44 pm

Hi Skybound

The problem with the adverse yaw can be sorted out by fitting a ventral fin and bigger rudder as can be seen on the attatched photo of my Cheetah. I used to have lazy feet when flying my Cessna but after a 2 hour conversion you will handle a Cheetah just fine. It will also make you a better "blik" aerie pilot who now knows what rudder pedals are for. :lol: :lol:

Rod the stiff throttles are common but when you start flying it you will actually appreciate the stiff throttle which prevents throttle creep.

Enjoy ETC - it is cheap affordable fun flying!!
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Re: Adverse Yaw

Unread post by Stephan van Tonder » Tue Mar 10, 2009 8:50 pm

Well it's basically one of those pub talk items with some truth. Most of the LSA types suffer from some adverse yaw when compared to bigger 'blik' and it certainly is not limited to the cheetah. I have flown a Ekolot/sabre JK05 and it almost more sensitive to that. I think it probably relates to the short moment arm due to their relative size and width. One thing is for sure - If you have forgotten how to use the rudder pedals you will be re-aquiring that skill shortly :-) But it certainly doesn't make it an unpleasant aircraft to fly.
The Bigger ventral fin was not to sort that out but to help with the self recovery from an incipient spin which apparently was a requirement when they were certified for PPl training(that is if I understood vladimir right).
The cheetah I fly also has the ventral fin and you still have to fly the ball. Guys it's not a big thing and you'll get used to it quite quickly.
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Re: Adverse Yaw

Unread post by John Boucher » Wed Mar 11, 2009 8:26 am

I agree with Stephan...

Learn to use rudders. It becomes second nature in the Cheetah and you don't even realise it after a while. :D
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Re: Adverse Yaw

Unread post by Roger » Wed Mar 11, 2009 9:59 am

Thanks guys.

Rudder feet not too fast asleep yet - used to fly a Kitfox taildragger.
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Re: Adverse Yaw

Unread post by John Boucher » Wed Mar 11, 2009 12:48 pm

If a rudder was not necessary on an aeroplane they would have built it without one (like the stealth bombers that need computers without moisture to fly the bloody thing) :D
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Re: Adverse Yaw

Unread post by Big Al » Wed Mar 11, 2009 6:18 pm

So what's the story is a ventral fin a nice to have or a need to have. I have been flying without and it doesnt seem to be a hassle. To have a ventral fin fitted is 15k, shouldnt i rather spend that on beer :D :D :D
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Re: Adverse Yaw

Unread post by rhodie » Wed Mar 11, 2009 8:44 pm

Big Al wrote:So what's the story is a ventral fin a nice to have or a need to have. I have been flying without and it doesnt seem to be a hassle. To have a ventral fin fitted is 15k, shouldnt i rather spend that on beer :D :D :D
Give Rainbow aircraft a call. I had a ventral fin fitted late last year, at a cost of R 2,040.00.

Neil
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Re: Adverse Yaw

Unread post by Stephan van Tonder » Wed Mar 11, 2009 8:45 pm

Big al - don't bother - if you know how to use a rudder and not regularly do incipient spin training rather spend the money on beer.
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Re: Adverse Yaw

Unread post by Flybynite » Thu Mar 12, 2009 6:31 am

Allan

Listen to me - I flew your plane from Jhb to Fapm to deliver and i fly a Cheetah with a ventral fin - BIG difference!!! Fit the mod! It definitely helps a lot in turns and might just save your life one day.

Regards

Larry
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Re: Adverse Yaw

Unread post by rod smith » Thu Mar 12, 2009 7:06 am

Fortunately ours came with the ventral fin fitted. I remember flying with a friend in his Aeronca, way back. If you stepped on the rudder (no aileron) she simply yawed and flew sideways without altering heading for a while.

Rod Smith
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Re: Adverse Yaw

Unread post by rod smith » Thu Mar 12, 2009 7:11 am

PS to the above post

I omitted to mention that I would spend the money on beer anyway, fin or no fin, so I am glad that we have one. Which leads to the obvious "fun or no fun" chirp!

Rod Smith

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