Raf trim tab kit....

StanFoster

Active Member
Joined
Nov 16, 2003
Messages
16,895
Location
Paxton, Il
Aircraft
Helicycle N360SF
Total Flight Time
1250
Still cleaning out my RAF excess....I have this trim tab kit. Everything in the picture goes.

$50.00 ...plus shipping.


Stan
 

Attachments

Last edited:

route66

Gold Supporter
Joined
Oct 12, 2004
Messages
902
Location
Parks, AZ
Aircraft
c-182/ RAF AAI Mod.
Total Flight Time
2000
I have one of those and had no idea what it was. It had no labels and I never saw it in any plans so I just put it on a shelf in a box labeled "?". I'll have to take a close look at your picture to maybe put it with my other parts labeled"?". Stan, Do you have any paperwork or plans for it's use and instalation? If so could I get a copy to put in my new box labeled, RAF Trim Tab Kit? If I ever sell it I'll buy you dinner at Benson Days or?
Thanks,
 

asmuzsr

Senior Member
Joined
Mar 16, 2004
Messages
797
Location
Clearwater, Florida
Aircraft
RAF2000 with stab
Total Flight Time
690
Doesn't the SparrowHawk have a similar trim tab on the rudder? I thought I read that somewhere.
I had one on my first RAF. Worked great, though I never did fly with the doors on. In Florida if it's that cold I usualy don't fly.
 

Harry_S.

Gold Supporter
Joined
Oct 30, 2003
Messages
5,649
Location
Ocala, Florida
Aircraft
RAF2000
Total Flight Time
2000+ hrs.
I have one of those and had no idea what it was. It had no labels and I never saw it in any plans so I just put it on a shelf in a box labeled "?". I'll have to take a close look at your picture to maybe put it with my other parts labeled"?". Stan, Do you have any paperwork or plans for it's use and instalation? If so could I get a copy to put in my new box labeled, RAF Trim Tab Kit? If I ever sell it I'll buy you dinner at Benson Days or?
Thanks,


Paul:

I'll look around and see if I kept the instruction sheets.

It was rather easy to install, looks good abd works great.


Cheers :)
 

asmuzsr

Senior Member
Joined
Mar 16, 2004
Messages
797
Location
Clearwater, Florida
Aircraft
RAF2000 with stab
Total Flight Time
690
Address

Address

Ok Stan I just sent one off your email address and not a reply. If you don't get it then just call me 727 744 1249.
I'll be up till 2 today and all day tomorrow and Saturday.
 

Harry_S.

Gold Supporter
Joined
Oct 30, 2003
Messages
5,649
Location
Ocala, Florida
Aircraft
RAF2000
Total Flight Time
2000+ hrs.
I found it

I found it

Okay...I didn't throw the "Installation Manual for the Snider Anti-Servo Kit" away.

It is a manual (13 pages) and very well presented. Typed instructions, very concise information and nice close-up photos. There are photos on every page, showing measurements and assembly. You won't find too many assembly manuals laid out as well as this one.

Allright...I can't do justice in duplicating this manual. My scanner and printer went south on me. Xerox would not do it right, so...

I can mail this to one of you fellows, who could then duplicate it and send to whoever requests a copy.

So...whom should I send it to?!


Cheers :)
 

asmuzsr

Senior Member
Joined
Mar 16, 2004
Messages
797
Location
Clearwater, Florida
Aircraft
RAF2000 with stab
Total Flight Time
690
Manual

Manual

I'll do it Harry. You can send it to

Tony Smuz
29835 69th Way N
Clearwater, Florida 33761

And Stan if you sill haven't got it by email there it is.

Thanks Harry.
Now who wants a copy. I'll be able to get some out next week.
 

Harry_S.

Gold Supporter
Joined
Oct 30, 2003
Messages
5,649
Location
Ocala, Florida
Aircraft
RAF2000
Total Flight Time
2000+ hrs.
Okay Tony.

I'll see if I can get a big envelope tomorrow, 9 x 12, it's big pages, and send it to you.

It is top notch quality.


Cheers :)
 

asmuzsr

Senior Member
Joined
Mar 16, 2004
Messages
797
Location
Clearwater, Florida
Aircraft
RAF2000 with stab
Total Flight Time
690
Manual

Manual

Thanks Harry
I figure with that and the kit to go by I can make another kit for my plane. It has the same problem as the RAF with doors on. I know it was great on my first RAF. Just flew around and never touched the pedals.
 

Harry_S.

Gold Supporter
Joined
Oct 30, 2003
Messages
5,649
Location
Ocala, Florida
Aircraft
RAF2000
Total Flight Time
2000+ hrs.
Stan and Tony;

There was nothing to it, 'twas my pleasure and you're welcome.


Cheers :)
 

route66

Gold Supporter
Joined
Oct 12, 2004
Messages
902
Location
Parks, AZ
Aircraft
c-182/ RAF AAI Mod.
Total Flight Time
2000
Thom, I have one just like Stan's for sale if you need one. Let me know. How about a prepainted tail & matching tailwheel pant? Guess I need to start my own thread for all my misc. parts.
 

Attachments

asmuzsr

Senior Member
Joined
Mar 16, 2004
Messages
797
Location
Clearwater, Florida
Aircraft
RAF2000 with stab
Total Flight Time
690
Trim kit

Trim kit

Sorry just saw the post Stan. Thanks.
I'll be laying it out ont the hangar floor with a circle drawn around the size of a gyro and telling everyone it a stealth gyro.
I may be interested in the other kit to try on my plane. It has the same problem as the RAF with the doors on.
 

dragonflyerthom

Platinum Member
Joined
May 24, 2006
Messages
4,742
Location
Arkadelphia, AR
Aircraft
RAF 2000 GTX SE
Total Flight Time
183FW 132Gyro
Brandon I just saw your post. How much?? Yes I would like one. Those are really neat pic. and Paint.

You can ask Stan or Ron. They will tell ya I deal really quick. I Pay by postal money orders. PM me
 
Last edited:

route66

Gold Supporter
Joined
Oct 12, 2004
Messages
902
Location
Parks, AZ
Aircraft
c-182/ RAF AAI Mod.
Total Flight Time
2000
Thom, I sold it to, (Quick Draw), Larry Boyer this morning. If you would like I will make a template of the trim tab so you can build one. I wish I had read your post before he called.
 
J

johnsnider

Guest
Hey Guys, John Snider here. Harry e-mailed me and let me know that there was considerable interest in my anti-servo kits here on the forum. I do still have kits available and the price is $275 plus shipping. The kit is very complete with all hardware, rivets, cable, etc. included and as Harry mentioned, the installation manual is very detailed so you can't hardly mess it up.

Below is an explaination of the tab but I was unable to get pictures attached. If someone is interested please e-mail me directly and I can send you pictures. Be sure to e-mail me directly as I rarely get a chance to visit this forum but will try to check in occasionally.

John Snider
[email protected]
812-890-8257



When a RAF 2000 or any aircraft for that matter is yawed to one side or the other, the relative wind strikes the cabin from the side. This not only results in a direct force being applied to the upwind side of the cabin, but also a low pressure on the downwind side. The cross sectional area of the cabin of a RAF 2000 is greater than the cross sectional area of the vertical stabilizer and rudder combined (vertical tail) when the doors are on. With the mast representing the yaw or vertical axis, (not exactly but very close) there is more area in front of the yaw axis than behind. This is somewhat analogous to an arrow with the feathers at the front. It wants to swap ends and fly backwards. The only reason that is does not is because the pilot senses the yaw and reacts by applying rudder which has enough authority that it can overcome the forces being applied on the cabin. The pilot is essentially acting as a yaw damper. Unfortunately, if the pilot removes his feet from the rudder pedals or worse yet, a rudder cable breaks, the RAF will swap ends in flight. When the doors are off the situation is greatly improved as the air can simply pass through the cabin in yawed flight but there is still some tendency for the aircraft to diverge from coordinated flight once a certain angle of yaw is reached.

The above can be easily illustrated by standing twenty or so feet to one side or the other of the RAF, directly abeam the mast and facing the gyro. I will use the left side for this discussion. With the rudder perfectly aligned with the vertical stabilizer, it can be clearly seen that the cross section of the cabin is larger that the cross section of the vertical tail and that the mast or pivot point is very nearly half way between the two. Now imagine that the wind is your eyes and it sees what you see if the aircraft were in a 90 degree yaw. In the absence of rudder control, the wind would blow the rudder to the right, not only reducing the cross section of the vertical tail even more, but also effectively applying a nose right rudder command which is exactly the opposite of what is needed in this situation.

An anti-servo tab is a form of trim tab that is hinged and thus moveable. It effectively acts as an aerodynamic centering device by moving in the same direction as the rudder when the rudder moves. This movement tends to return the rudder to its neutral position when deflected. The more deflection there is the greater the force trying to return the rudder to neutral.

The anti-servo tab replaces the existing fixed trim tab on the rudder. All but about one half inch of the existing trim tab is cut off leaving only enough to rivet a piece of piano hinge to. The anti-servo tab is nearly the same shape and size of the portion of trim tab that is cut off and has the other half of the piano hinge riveted to it allowing this new tab to be hinged and thus movable on the rudder.

This new movable tab has control horns on it similar to the control horns on the rudder itself. Two cables link these control horns to a bracket attached to the keel beam. The cables are routed inside the rudder and are crossed so that when the rudder moves to the right (nose right) the tab also moves right. The opposite is true for left movement. The movement of the tab is caused by the movement of the rudder and requires no input from the pilot.

The installation of the anti-servo tab reduces the undesirable yaw characteristics of a RAF 2000 to a much more acceptable level without the huge cost, weight, hassle of preparing and painting, and detriment to the stock look of the RAF associated with adding more vertical tail.

The results of installing the anti-servo tab on my RAF 2000 are as follows:

Doors Off: The gyro flies in perfect coordinated flight with my feet off of the rudder pedals at cruise power settings. (The tab can be ground adjusted to provide coordinated flight for the power setting you use most often. Most likely cruise.) When power is higher, some right rudder pressure is required. When power is lower, some left rudder pressure is required.

Doors On: The gyro is substantially easier to control in the yaw axis and requires much less effort to maintain coordinated flight. If I remove my feet from the rudder pedals, the gyro may fly for some time before eventually yawing to the left or right about 10-15 degrees. It no longer will continue to diverge and swap ends in flight. If I intentionally apply sufficient rudder in either direction to create a yaw of well over 25-30 degrees, the gyro will return immediately to the 10-15 degree yawed condition allowing for continued flight and landing in the event of a rudder cable failure.

Power Off: When power is removed or dropped below about 3500 RPM, the anti-servo tab does not have sufficient airflow across it to do its job effectively. Consequently, at low or idle power settings and engine inoperative, the gyro behaves almost exactly as it did without the anti-servo tab installed. However, anytime one is flying with reduced or no power as in approach and landing or engine out landing, they would or should have their feet on the rudder pedals anyway. If you have an engine failure and rudder cable failure all in the same flight then you’re just having a really bad day.

I am not advocating flying around with feet not on the rudder pedals but this tab will allow the pilot to remove his feet from the pedals to relieve cramps and readjust for comfort without having the gyro try to swap ends. More importantly, it makes the gyro much less likely to become uncontrollable in the event of rudder cable failure.


John Snider
[email protected]
812-890-8257


John Snider
 
Top