Nobler ARF Incidence..

My Nobler ARF flies great except for one little problem, it just doesn't grove like I feel it should. This past weekend at the Tulsa contest Jim Lee flew it and after the flight commented on the same problem. Later it was pointed out by Bill Wilson of Dallas that the wing, stab and engine incidence on his Nobler was off by quite a bit.

I have two of the Great planes incidence meters and when I am building I usually spend several hours just making sure everything is perfect. Dummy me, didn't even think to check the incidence when I put my ARF together and now wished I had.

Bill gave me a run down in how to fix it after the fact by shimming the engine and taping tooth picks under the stab, pretty neat trick but the important thing is to be sure you check the alignment of the wing, stab and engine. The wing saddle in the ARF may not be exactly perfect.

>I have two of the Great planes incidence meters and when I
>am building I usually spend several hours just making sure
>everything is perfect. Dummy me, didn't even think to check
>the incidence when I put my ARF together and now wished I
>had.
>
>Bill gave me a run down in how to fix it after the fact by
>shimming the engine and taping tooth picks under the stab,
>pretty neat trick but the important thing is to be sure you
>check the alignment of the wing, stab and engine. The wing
>saddle in the ARF may not be exactly perfect.

I saw what must have been a similar issue this weekend. One of the ARF Noblers seemed to be willing to turn outside much more quickly than inside. The pilot was none too impressed and didn't want to spend any time working on it, but was clearly an alignment issue.

A different ARF Nobler appeared to fly quite well. Unfortunately, I didn't get a chance to fly either of them, but Ted did, and he might be abke to give a pilot's report. For $99, it's really hard to go too far wrong!

Yep, I forgot to mention that mine also turns snappier outside than it will inside.

my flite streak does the same thing turns outside better what can i do?

Just make sure the engine and stab are 0-0 with the wing. On the Flight Streak the easy fix is just to point the engine up a little. You may simply be able to loosen the bolts, pull the front of the engine up and tighten them back down.

Back when we could buy a new case for nothing in any hobby shop we just drilled or filed out the engine mounting holes so we could get a little more if necessary. If it is an OS LA drill the darn thing, if it is a G-21 35 Super Tiger you may want to think about it

its a la25 hey do want those supertigers back i seem to have 5 of them now and you sound like you might be getting into combat? besides im useing la25 on bladder and i like it see ya brad

As long as you want them you can keep them, if you ever decide to get rid of them because you won't use them, then yes I would like to have them back.

Brett, I dont know if you heard, Jim Goss was so upset about the way his Nobler flew he sold it to Lewis Lingwood for Fifty bucks. I think he gave up on it to soon.

>Brett, I dont know if you heard, Jim Goss was so upset about
>the way his Nobler flew he sold it to Lewis Lingwood for
>Fifty bucks. I think he gave up on it to soon.

I think so too. There wasn't anything that couldn't have been fixed.

Do you know how far off it actually is?

I was afraid someone was going to ask this question

Ok, there is the easy way and the hard way, the easy way only works before you have the flaps and elevator glued on. Without the flaps on the airplane you can use a Great Planes incidence meter to check the wing, stab and engine. Instructions come with the meter and they are not that expensive.

When I built my work bench I not only made sure it was flat but also level, the level part is real important for this discussion. I set the wing on two identical shotgun shell boxes, one on each side of the fuselage, under the wing. Put the incidence meter on the wing and shim up the rear of the fuselage so the wing has 0 incidence which is also level with the work bench. I bought a small pocket level from sears that has a V grove on one side that will rubber band to the prop shaft and is also small enough to sit on the stab. Once you know the wing is at 0 the rest can be checked with the level.

If you already have the flaps and elevator glued on you have to do it the hard way. I would use the same shotgun boxes but then you will have to set the wing level by carefully measuring the leading and trailing edges in reference to the work bench. A piece of music wire that will slip down between the fuselage and flaps is probably the best measuring device. Measure and mark the music wire at the leading edge, then the trailing edge until you are sure the wing is level with the bench. Then you can use the level to make sure the engine shaft and stab are parallel with the bench.

Some designs require a slight amount of positive incidence in the stab which is easier measured with the incidence meter but can be calculated. Someone on the old RCO site noted that a line projected 12 inches from the trailing edge of the stab raised 1/8 inch is .6 deg positive incidence.

Yes, I checked the incidence on mine before assembling. Luckily, the Chinese girl that jigged mine up did it right. The hardest part of the assmebly was getting the elevator and flap adjusted to neutral. Must of worked about 2 hours to get it perfect. A less pickey person would have spent about 10 minutes. Flies the same upright, inverted, going up, or going down. I love these things, but like any plane it does require attention to the basics during assembly. Yes, by all means, check and re-check incidence before the expoxy sets.

Since my wing is only being held in by the dowel and the bolts, I guess it is adjustable. I didn't pay any attention at the time of "assembly" (AOM rule!!--but let's not go there!) , so maybe I ought to break out my incidence meters from the original packaging (won in a club raffle ~5-6 years ago) and give it a look.

Many folks feel that a Nobler will always turn sharper outside, due to the drag of the wing set quite far below the thrust line.

Chris Lella's late 70's or early 80's series of articles in MA (Balancing for Pitch. Roll, and Yaw in CL stunt ships) supports this idea.

I spent quite a bit of time with the incidence meter jigging my Noblarf dead straight, but to my hand, it feels like it turns sharper outside. Nothing that can't be fixed with a handle adjustment, though. To someone who grew up flying Noblers, it might feel normal. Who knows?

I'm just a simple Ice Cream Man . . . wanna chime in here, Brett?

Rick Campbell

Isn't this why some designs need slight positive incidence in the stab?

I found that on me first flight I had a tail down attitude.
I shortened the flap to stab pushrod 2 turns and it now groves just fine.
One note on the fuel tank. Toss it. I had much engine trouble and changed the tank. I then decided to unsolder the kit tank and it was all rusted inside. They must have used acid core solder and did not clean it out. I did return it to Top Flight but have not received any replacement as of yet. I really don't want one of theirs anyway.
This is a fun aircraft and is a sign of the future weather anyone likes it or not. It will not replace the top dogs but if Brodak brings 3 new ones out I will surely try them too.

DICK BYRON