DMyer

My Feedback: (2)

I am putting together my first predator and I noticed when I set it up on the bench to check all the incidences.... the stab, as routed into the fuse, has about 2 degrees of negetive(full bubble). That can't be right. What is everyone setting the predator stab to? I assume it should be zero or at most just a smidgeon of negetive. Thanks.


Dan

djlyon

Yer right. Set it to zero. The minus 2 deg is an error I think. I built mine with the minus 2 deg and it took a 1/16 shim under the trailing edge of the wing to get it to fly right.

Denis

aseaholm

My Feedback: (1)

I put the tail feathers in my Predator this past weekend. It was pretty close all the way around. The wing and tail saddle were right on 0-0 degrees incidence. The firewall had about 1/2 degree of negative incidence.

In the past 0-0-0 incidence was common practice. 2 degrees will definitely be noticeable and there have posts here stating this is a common problem. The advice has been to sand the tail saddle till its back to 0 with the wing. I must have got lucky with my kit.

I also need to put the incidence meter from tip to tip to see there is any twist. I understand this is also a fairly common problem...

A.J. Seaholm

DMyer

My Feedback: (2)

Thanks everyone... that is what I thought... no big deal to fix. I wonder how the quality control for the GP Viper ARF will be? I am putting it on my XMAS wish list.


" I also need to put the incidence meter from tip to tip to see there is any twist. I understand this is also a fairly common problem..."

Mine has about a quarter bubble on the outboard section of one wing.... I plan to slice it on the underside from the end of the aileron to the wingtip and bend/re-glue to match the other wing.

Dan

PJ_TankPilot

>>I also need to put the incidence meter from tip to tip to see there is any twist.

One of mine was the Predator from Hell. Everything measured spot on but the two wing halves had different airfoils. It cork screwed like a Tasmanian Devil.

It’s easy to check for this condition using the sun or a bright incandescent light.

DHG

My Feedback: (7)

... remember that just because the cutouts in the fuselage sides appear perfectly level, it doesn't mean that when you set the "V" tail in there, it will be level. That's because the fuselage sides move farther apart as you go forward, which allows more of the "V" to drop down into the hole at the front than at the back.

I don't know why the kitmakers don't just put a flat tail platform in there, or run the fuselage sides exactly parallel with each other for the last 5 inches so level cutouts would give zero incidence. That would make the "V" tail installation goof-proof.

Mr. Goof

PylonWorld

Hey Goof Off,

Some kit makers have.

The kits just aren't available yet.

StanDouglas

Dan,
Before you go hacking and bending and reglueing your wing, you might want to try the method of "Straight Racing wings". Written up by Darrol Cady. I have personally seen this work on several Predators as well as other aircraft. You can find the article at:
http://www.darrolcady.com/Racing_Inf...tips-tech.html

While you're there also check out the mods for the Predator:
http://www.darrolcady.com/Neme-Q/predator.html

Regards,
Stan

DMyer

My Feedback: (2)

Stan,

Thanks... I had seen Darrol's site and I am doing all the recomended fixes/improvements. In addition, I significantly widdened the wing saddle and I will also pot the wing on. I just can't bring myself to clamp a wing onto something so skinny... frail looking as it is stock. I am also triangling the entire front end in addition to pinning and the 1/8 front plate. By my calculations this thing is built pretty light and can easily withstand a significant amount of targeted strengthening from former B forward without going over 3.5 LBS. I am excited to try this thing out as all the 424 planes I used previously this year were old worn out, much repaired, way too heavy 428 planes. I was turning some pretty decent times with those planes... can't wait to try something on weight.

Dan