Twinn Rex

[Trooper1276]

Alright since this forum has been a little quite lately I figured I'd send a few pics of my new Twinn Rexx. I'm not finished with the body yet (see pics) but I've flown her about six or seven times and got the bird pretty good and trimed out. The actual heli kit only takes about 4 days to get in the air. The actual work begins with the body. I have spent about 40 hours on the body kit so far and still have a week or so before I think I'm finished. I'm running a stock setup per Joes website and modeling an RAF bird thats got a good paint sceme that looks good and will help with orientaion when its finally out of the front yard.

I made a hatch for the batt in the bottom using RC control surface hinges and needed to move some electronics around to get at everything once the body is on.

Also I would like to ad a few tips for those that are going to build this kit.

1. install the servos and the body stand offs before the frames are joined (trust me on this one)
2. read everthing on joes website twice
3. get a good flat head screw driver
4. learn to love or at least tolorate vacumform plastic.
5. the A and P servos in the rear need to be installed on the inside of the frame for the body to fit right which means your going to file or dremal some bolts so the servo links will clear.


Right now I'm finishing the engine pods and homemade decals plus some touch up with the airbrush. should have the masks off the windows in a day or two.

Enjoy the pics...Should have some of the finished bird with a vid maybe next week.

[Trooper1276]

Couple more plus the decals I made on the computer. I hope the decal paper I got off the internet really works as advertised?

[v22chap]

Trooper ... looks great ...love your battery cover idea :thumbup:
Just flew mine for the first time at our club meeting ... drew a lot of attention even in the no dress form I have it in right now ......this was the first time the wind around here was low enough this yr to be out side with it much :arggg:

[Trooper1276]

Here it is finished. time to move on to the mini titan cobra that came in the mail today.

[sikorskys76]

Do you have any videos of it flying?

[Trooper1276]

sorry. no vids yet, but I am shopping for a new camcorder and will post a vid when I can. BTW I'm having some issues with the DCP at the moment and still tweeking the setup. It hovers ok but in forward flight its doing some really strange things. Maybe whenI get a vid some of you guys can figure out whats going on.

[sikorskys76]

Cool..


What kind of weird things? drifts?porpusing?

[Trooper1276]

It will be flying almost hands off then the rear end will just fall. this happens three four times a pack. Thats in HH on the DCP it doesn't do it in rate mode. I would fly in rate mode all of the time but it is more stable in HH when the butt itsn't dropping.

[Trooper1276]

Shot some video today. Quality sucks but here you go

http://www.youtube.com/watch?v=VBkP6Ac3G48

[ShooShoo]

Here's an excerpt from the TMP Twinn Rexx manual regarding FRVI.

"All tandems experience Front Rotor Vortex Interference (FRVI). It occurs at low flying speeds and at
high angles of attack. From a stationary hover gaining forward speed, at some speed the front rotor
vortex will begin to extend back and interfere with the lift generated by the rear rotor. This will cause
the tail of the aircraft to drop. To correct, apply forward stick and some power. The sooner you apply
the correction the smaller the effect of FRVI will be.
The DCP gyro will handle this condition for most flight conditions. It will stay ahead and compensate
automatically up to a point. Understand that there are many flight conditions and attitudes beyond the
control power of the gyro to compensate. It is recommended that you practice with the DCP gyro in
"rate " mode to develop a "feel" for when these conditions occur and the reflexes to compensate.
Practice will allow you to recognize the onset of FRVI and allow you to recover or even prevent an
occurrence."

I've observed that when the tail drops the HH gyro on the DCP channel tries to keep the heli level which results in it quickly losing altitude due to the overall loss of lift. This happens going into FF from a hover and vice versa. The good thing it's predictable you just have to get used to it. It also doesn't happen flying sideways, but only flying sideway looks a little silly.

Shawn

[Chris]

Trooper1276

What did you use to hold the two halves of the body together as I cannot see any screws on yours.


Many thanks

Chris

[Trooper1276]

There are four main screws that attach to standoffs on the fusalage and there are a three smaller screws around the tail to hold the halves together. They were all painted to match and the two rear screws are covered by the engine nacelles which are held on with magnets. seven total screws.