Fidgit contest plane pics
 

I just posted some pics of my contest plane about an hour ago and the post is still not showing.
what did I do wrong?

Trying again...

The Fidgit is almost there. I just have to make a cowl, windshield, fuel hatch, and maybe landing gear. The cowl will take the longest, but I have a problem. I can't find a motor mount. I have been to every hobby store in a 50 mile radius and still cannot find a mount for the big-mig. Anyway, I should be able to complete the plane on time.

RE: Fidgit contest plane pics
 

That's a good looking plane with a pretty unique upper wing! I have never seen anybody try pivoting wing panels. Are the pivots points going to be supported by the lower wing interplane struts [outboard]? It's good to have that long nose, most 1/2A designs need about 4" from the L.E. of the wing to the firewall. I think you will end up with a slick plane when you're done!

RE: Fidgit contest plane pics
 

Thanks CP. Yes, the upper wing will be supported by struts at the wing tip. If you look close at the first pic, you will see the copper tube that the steel rod will slide into to allow the wings to pivot.

I made the nose a little short because I was thinking that with all the weight of two wings and engine, and with no horizonal stab, it would be just about right?

RE: Fidgit contest plane pics
 

FP, I see the method to your madness, I didn't realize this plane is a SCIMITAR in disguise! You can always shorten the nose easier than making it longer, so I think you are approaching this design exercise from the right end. The longer you make a torsion bar, the more whip like it will get, so I'm wondering how far into each wing panel the torsion bar extends before it gets anchored to the structure?

RE: Fidgit contest plane pics
 

Maybe I explained poorly. The top wing will be attached to the lower wing at the wing tips by an interplane stut.

RE: Fidgit contest plane pics
 

Now this is a unique design. I'm going to be looking forward to hearing about the flight report. Way to GO!

RE: Fidgit contest plane pics
 

Very cool.[sm=cool.gif]

Here's a link to a mount that fits the Norvel .061.

http://www2.towerhobbies.com/cgi-bin...?&I=LXB867&P=0

RE: Fidgit contest plane pics
 

Bipe is right. I have the Dave Brown mount and fits Norvel 061 REALLY well.

I'm curious about pitch control - with no horiz stab the plane relies on the offset wings? It looks like a very short coupling. I assume you are mixing the upper wing panels as elevons?

RE: Fidgit contest plane pics
 

I plan on using the top wing as elevons, similar to the Scimitar planes like CP said.

I have used the dave brown mounts and like them. I only need the mount, and can't bring myself to justify ordering ONLY ONE THING from tower. It would seem such a waste.....

RE: Fidgit contest plane pics
 

Well I'm placing an Tower order tonight. If you can wait just a couple more days I can zip one to you ASAP.

RE: Fidgit contest plane pics
 

I just dropped by the hobby store during lunch, and whatta know, a .049 motor mount.
Its a Hayes Big N' Bulky, but I got it. This thing is at lest 2!QUOT! long. I guess I can always mount the motor all the way at the front if I am having balance problems, and cut it off if the balance is o.k.

BTW: Thanks for the offer Mr. Flugge

RE: Fidgit contest plane pics
 

NP, I'm eager to see you get 'er completed!

RE: Fidgit contest plane pics
 

Got'er covered. Weight is 8.9oz with out radio, engine and tank. I think I can keep it under 16oz. My planes always seem to add more weight than the actual components. Here are some pics of the covered plane.

RE: Fidgit contest plane pics
 

Poodle, your latest pics made me go back and re-read the early posts. I had not noticed that you intend this as a flying wing style of model. But there's a problem. The airfoils you are using are not plank style positive pitching moment airfoils. So basically this isn't going to work other than for the time it takes to arrive at the crash point. The upper wingerons will provide pitch and roll but you need a stabilizer. You don't need elevators. Just the fixed stab will do the job.

If you want to try it as is I suggest a field of very tall grass or similar soft stalk crop. And get ready to duck if need be.

RE: Fidgit contest plane pics
 

Looks beautiful, FP! Should be a lot of excitement in your area to see the first flight!

RE: Fidgit contest plane pics
 

Sharp looking plane! What did you cover it with? I hope it turns into a nice flyer for you. Looks great.

Derek

RE: Fidgit contest plane pics
 

Bruce - Could you please elaborate on the need for a plank! type airfoil. I have seen a plane at this web site http://users.adelphia.net/~pjburke1011/ that has a horizontal stab that drops off in mid flight by action of a servo. The plane is then flown as a scimitar type with elevons.

Ragwing - The covering is just money-cote, I think its copper and pearl white. I am not really pleased with the pearl white, as it is not totally opaque and allows my building errors, pen marks, and the underlying covering to show trough.

RE: Fidgit contest plane pics
 

I just cobbled together this thing out of scraps so that I could get a handle on how this might work. I balanced it at about 12% and when the AOA of the upper wing is increased, it climbs and vice versa. It does roll when the AOA of each side is different from each other, but it requires much more up than down. I would think that if you want to turn effectively that you'll want to increase the AOA of the opposite side from the way you want to turn, rather than decreasing the AOA of the side you are turning to, or it will dive.

RE: Fidgit contest plane pics
 

The trick to getting this plane to fly well might be to have a seperate servo for each wing panel so all programming possibilities can be tried. It would also be nice to have a full size mock up like BF built to do all the down and dirty test flying with.

RE: Fidgit contest plane pics
 

Wow! Thanks for the info and the mock up Bipe. The foam cores on your mock up look better than the ones I cut for any of my !QUOT!nice!QUOT! airplanes.

I should have done a little more research prior to construction. It seems that the C.G. needs to be from 10% to 15%. When I made the nose short and the tail long, as CP noted, I thought the C.G. would be the normal 25% to 30%. I still think I can achieve the required C.G. by placement of electronics, but if needed I may add tricycle landing gear (UNGH!) to get to where I need to be.

And again, thanks for the advice and encouragement

RE: Fidgit contest plane pics
 

You're welcome FP. A little chuck glider can really help when designing something new. The cores were rejects from another project; I forgot to clean the wire before cutting and there were a few lines on the cores.

RE: Fidgit contest plane pics
 

OK. The completed aircraft weighed 18.5oz. I set the C.G at about 13%. Test glides showed that the plane wanted to Immediately nose dive. This dive was unaffected by the application of Up or Down control input. I then (I'm not the sharpest burnt out light bulb) tried a power on hand launch, which ended in a power-on nose dive into the ground. Fast forward to round two.

My new battery arrives and the weight of the aircraft is now 17.5oz. Further test glides with increased control through indicate more of the same, Nose dive into the ground. I then shift the C.G Back to around 25%. Test glides now do not nose dive. Now for the power on test (still not the smartest tool in the bowling ally). The norvel is screaming and a light toss turns into about a 45 degree climb out with a slight roll to the right. Left aileron is added as well as a little down, more left aileron is added with full down, now I am rolling into a dive and have no control. Reduce throttle and it smacks the ground. The wing mounting block is broken and the rudder servo is now loose. Tough little bird.

Any idea why I have NO control. I expected it to be very sensitive since I am moving an entire wing, but it does not seem to have any effect. The top wing which moves has a cord of about 4!QUOT! and is full span. The pivot is at the spar around 25% MAC. The control movement is about 1!QUOT! each way at the trailing edge.

I think I may just put a horizontal stab on and call it a day. Any suggestions?

RE: Fidgit contest plane pics
 

HI FP, at this point I suggest that you rig up a tethered test with this thing so that it is free to rotate and pivot. If you can rig this up in the back of a pick up truck, then get your R&D work done at 50 mph on some back road.

RE: Fidgit contest plane pics
 

Going from 13% to 25% is quite a jump. Maybe try something around 17%. Are you using a throttled Norvel? If so, try a few glide tests with just a little bit of power and gradually increase it if all goes well.

RE: Fidgit contest plane pics
 

The only experience of any kind that I have with this sort of thing was with a MORRIS HOBBIES SUDUKOI that I fly 100% of the time with flaperons. One day it seemed like the loops weren't as tight as usual, and upon further review the elevator servo was locked at nuetral and I had been flying for at least that flight with the control surfaces on the wing only. That plane is balanced at 30%. I think this plane would be a lot of fun with a stabilator coupled to the wingerons.