Adverse Yaw

The versatile 3-axis Microlight from Rainbow Aircraft, manufactured completetly in South Africa.

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Big Al
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Re: Adverse Yaw

Unread post by Big Al » Thu Mar 12, 2009 8:01 am

Thanks for the replies

How many cheetahs are out there without ventral fins fitted that have pranged? I have to schlepp my aerie back to Springs, fork out 15k only to find that there are probably 50 cheetahs flying without :shock: If it was that dangerous wouldnt rainbow a/c have organised a recall on the cheetah? I dont mind fitting one and i am open to advice but now i must slip 15k past softness.

Allan
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Re: Adverse Yaw

Unread post by Cornell Blok » Thu Mar 12, 2009 8:32 am

rhodie wrote:
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

Allan I don't think you read all the posts :lol: :lol: :lol:

Any way if I was you I would listen to Flybynite he's got plenty hours on the Cheetha.

I don't think the Cheehta got a design flaw the fin will just provide extra stability. For any low time pilot it's a must have I think :?

R2040.00 for more piece of mind its a BARGAIN
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Big Al
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Re: Adverse Yaw

Unread post by Big Al » Thu Mar 12, 2009 9:07 am

Thanks Cornell

Ja, i am sitting with the quote in front of me which i received yesterday. R14388.30 to supply and fit a ventral fin and then because of the ventral fin mod i must also have a mod done to the rudder, elevator and vertical stabiliser. I certainly am open to advice and suggestions. A local pilot here has 400hours on the type and he doesnt have a ventral fin and wont fit one either, so all i am doing is gathering info in order to make an informed decision.

Perhaps others will add there bit as well, those with ventral fin and without.

Regards
Allan
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Re: Adverse Yaw

Unread post by MidlifeCrisis » Thu Mar 12, 2009 12:30 pm

I own ZU-EXF which was the 96th aircraft built,my plane was manufactured with the lower fin and I must say my feet are not bussey at all during landing,unfortunately I cannot comment on a plane without the fin but I realy enjoy my cheetah and i am glad we have this section available to swop ideas and experiences with our planes.
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rhodie
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Re: Adverse Yaw

Unread post by rhodie » Thu Mar 12, 2009 1:52 pm

Big Al wrote:Thanks Cornell

Ja, i am sitting with the quote in front of me which i received yesterday. R14388.30 to supply and fit a ventral fin and then because of the ventral fin mod i must also have a mod done to the rudder, elevator and vertical stabiliser. I certainly am open to advice and suggestions. A local pilot here has 400hours on the type and he doesnt have a ventral fin and wont fit one either, so all i am doing is gathering info in order to make an informed decision.

Perhaps others will add there bit as well, those with ventral fin and without.

Regards
Allan
Hi Allan, not sure why you have been quoted such a large amount, In Sept.2008 I had the following done;
Ventral fin.
3 Blade Kiev Prop and spinner.
Latest Joystick assembly.
T Bar Throttle system.
Heiners Luggage compartment.
Annual insp.
ATF.
Change of ownership.
Total costs R 24,303.00 Exc. V.A.T.

Regards
Neil
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Re: Adverse Yaw

Unread post by Whirly » Thu Mar 12, 2009 2:03 pm

rhodie wrote: Hi Allan, not sure why you have been quoted such a large amount, In Sept.2008 I had the following done;
Ventral fin.
3 Blade Kiev Prop and spinner.
Latest Joystick assembly.
T Bar Throttle system.
Heiners Luggage compartment.
Annual insp.
ATF.
Change of ownership.
Total costs R 24,303.00 Exc. V.A.T.

Regards
Neil
Neil/rhodie,

Enlighten me please, as I am put off by the Cheetha's throttle and joystick arrangement, what mods did they do on yours?

Whirly.
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Re: Adverse Yaw

Unread post by rhodie » Thu Mar 12, 2009 3:29 pm

Neil/rhodie,

Enlighten me please, as I am put off by the Cheetha's throttle and joystick arrangement, what mods did they do on yours?

Whirly.

Instead of having the ball at the end of the armrest, pushing forward and back for throttle control, you now have a T bar at the end of the arm rest with an up and down movement of your wrist to control the throttle. If you look at the photos posted on this forum by Stephan, there is a picture of my Cheetah (DZW) with the arm rests visable.
The latest joystick from rainbow instead of been straight, has about a 30deg. forward bend half way up, I find there is less arm movement required, especialy when flaring out.
I definitely prefer both of these latest mods.

Neil
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Re: Adverse Yaw

Unread post by Big Al » Thu Mar 12, 2009 4:47 pm

Perhaps i have to pay more because i live south of the Tugela.

Rhodie,

Before and after with the ventral fin, how was it?
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Re: Adverse Yaw

Unread post by Stephan van Tonder » Thu Mar 12, 2009 8:06 pm

new throttle
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rhodie
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Re: Adverse Yaw

Unread post by rhodie » Fri Mar 13, 2009 1:44 pm

Big Al wrote:Perhaps i have to pay more because i live south of the Tugela.

Rhodie,

Before and after with the ventral fin, how was it?
I can not comment on the before and after,as I only flew the cheetah a very short while, prior to the purchase of it, and that was on a very windy day. I fitted the fin on the advice of the instructor who trained me on the cheetah, ( Russell Bird, a very experienced pilot with many hours on the Cheetah).

Rhodie
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Re: Adverse Yaw

Unread post by rod smith » Sun Apr 05, 2009 10:09 am

Talk about bringing yourself down to earth (No pun intended!)

My first flight in the Cheetah was an eye-opener. Sure, we had a big crosswind, but I would not have been able to land the aircraft if there had not been an instructor with me. There is no inertia to speak off. The smallest rudder or stick movement seems to send her all over the sky. Lining up and flying along the centre-line was more than I was capable of doing. I was amazed to note the aileron yaw - move the stick to the right, for example, and the nose jumps up and to the left. Lead in gently with the rudder, followed a second or two later with the aileron and a smooth co-ordinated turn comes.

Rudder lazy? Who me? You bet! I am looking forward to learning to fly all over again.(Not all over the sky! Sheez, these unintended puns will return to bite me.)

Rod Smith
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Re: Adverse Yaw

Unread post by Stephan van Tonder » Mon Apr 06, 2009 11:12 pm

Welcome to the world of small airplanes :-) and then some pilots of bigger tin think lesser of us ;-)
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HansK
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Re: Adverse Yaw

Unread post by HansK » Mon Oct 05, 2009 6:09 pm

I agree fully with Rod Smith's description of the Cheeta's flying charactaristics. Not my cup of tea. I suggest they make the wing without ailerons (cheeper construction) and connect the stick to the rudder as the ailerons does not make the thing roll, just yaw. After two years of test-flying everything I could lay my hands on, I bought a Bantam.(Could not afford a Foxbat then) I actually like flying it in conditions where most other light aircraft stay on the ground due to cross-wind components and gusts - you just have to get the nose-wheel on the ground a.s.a.p. after touch-down to prevent weather-cocking in a x-wind. The rest is a non-event due to the large control surfaces - AND NO AILERON YAW.
Last edited by HansK on Fri Jan 27, 2012 9:01 pm, edited 1 time in total.
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Re: Adverse Yaw

Unread post by rod smith » Fri Nov 27, 2009 8:04 pm

Interesting observations, Hans. I haven't managed to get out to the Cheetah for weeks now. I need to fly. Getting withdrawal symptoms.

Rod Smith
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Re: Adverse Yaw

Unread post by Hennie van Zyl » Sat Nov 28, 2009 9:56 am

Taildragger Cheetah's have no ventral fin and it does not seem a problem.
How many tailees out there? Any tailee drivers care to comment?

I have ordered a new tailee as my strip necessitates it and I have
owned a few taildraggers- and all of them required footwork- the worst being the
Bushbaby 912 taildragger, which I found very twitchy.

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