Roban Apache 700 tail issue

[raptor50luvver]

I just wondered if anybody with the Roban 700 Apache could comment on how well the tail performs on theirs and if they had any issues.

We have a club member who has one and the tail is very loose inflight with no real hold whatsoever and it feels very vague ,continues on a bit after rudder input stopped or slowly bounces back the other direction.

It has a V bar Silverline fitted,we are all very familiar with the V bar setup,there are no vibes in log just good health thruout although the heli does have a low frequency vibration going thru it in the hover(horizontal stab and rocket pod mounts showing it).

We have tried a very low up to maximum tail gains,played with the stops and acceleration,optimizer is on and all this does not help the tail issue.

Mechanically everything looks Ok,there is no slop in the linkages anywhere and the tail slider runs lovely and smoothly on the tail shaft.

We are at a bit of a loss really,but I am wondering if one or more of the tail grips could be locking up under load,we also wondered if longer tailblades(115s) would maybe help a bit.

In a nutshell it really does feel like there is little in the way of a tail gyro there,two or three of us have flown it and all come to the same conclusion as its easier than just watching it in action when you try and fly it yourself.

So how are your tails please?

Any input really appreciated.

[ssmith512]

I run Edge 115mm tail blades on my Roban Cobra, which I am going to assume has a very similar tail to the Apache. I run 800mm main blades at 1200 rpm and I have no tail issues. I wouldnt categorize the tail response as "crisp", but it does not wander or overshoot and has no problem holding during high collective maneuvers. Futaba CGY750 for me.

I did not like the Roban tail grip assembly and replaced it with a Quick UK (Trex 700) replacement.

Hope you solve your issues.

[raptor50luvver]

Ok Steve

Thanks for the feedback,it gives us something to work with.

[Jackass1277]

My a109 grand had same issue. I had to put 105s instead of recommended 96mm and also have to change the tail drive gears to speed the tail up. But I'm not sure if you have the second option. So I would recommend going up in tail blade size first.

[Andy01]

I fitted 120mm (x2) tail blades on my Vario Long Ranger (2x 710mm main blades), and they are rock solid. I started with 107mm, and the tail held, but it was marginal, especially in a big banked turn in windy conditions.

As others have said, try go up a size or two.

Colin

[raptor50luvver]

Ok thanks Guys.

Will report back.

[RFCXPerT]

How is it going now? I've heard that the under size mounting tail bolts were too sloppy to hold the blades firm in place. But I do not know how to check mine.