RE: World Models Super Chipmunk 90
 

Well, it looks like tomorrow (Sat) is the day for my first flight of Mr. Chips. Irobbed an AR7000 out of another one of my planes and hooked it up. Ineed to review the programming before flight but, that won't take long. She's all dressed up and ready to fly.
I'm a bit worried about the ability to the G38 to pull this bird through the maneuvers Iwould like for it to perform. Ihaven't weighed the plane but, it sure feels heavy ....even with an empty tank. I'm sure it will fly but, how well is yet to be determined. If this engine doesn't perform they way Iexpect it to, I'll replace it with a 52cc Ihave in my "box". It will take a bit of work but, should fly the plane very well.
I'll post a flight review. The weather and the winds look good and I'm excited to get him in the air.

RJ

RE: World Models Super Chipmunk 90
 

Good luck, I hope all went well with the remaiden.

RE: World Models Super Chipmunk 90
 

It went very well for the first two flights. On the first flight I had a small amout of trimming to do and he smoothed right out. The second flight, after a high end carb adjustment, it was flying even better with more power and Iwas getting the feel for him. Iadded a bit more elevator and aileron throw and he handled very well. I shot a few approaches and landings and he handled very well without flaps as it was a bit windy.
The 3rd flight was going great too ...no adjustments needed, so Ifelt free to wring him out a bit. However, the engine died as I pulled the throttle back at the top of a hammer head. He was up wind at the north endo of the runway started down wind in a hurry so I pulled full flaps in hopes I could slow him down enough to make the runway. Iover-shot the runway and I tried to set him down in the rough off the south end when the left main wheel hit a hole or rut right after touchdown and tore the wings off. The left wing is in real bad condition but, the right wing can be repaired and recovered. Imay be able to use the right wing as a template to make ribs for the left wing. The inboard half of wing behind the spar is missing.
I've never tried a repair this big so, don't know if I can do it successfully or not. I've written to a place that sells laser cut kits to see if they can cut a couple of wings for this bird. I've also posted "wanted"adds on the major Forums so, we'll see what turns up.
Ihate that it happened and don't know why the engine died. It ran great during the second flight but, was still a bit rich on the bottom end. I do plan to repair or replace the wings. I really like the way this bird flies.

RJ

RE: World Models Super Chipmunk 90
 

Man! that's really disappointing to have two good flights then a bad one that sends you back to the building board [:@] I know you will have your Chipmunk up and running soon. The same thing happened to me on my third flight the engine quit at idle, not sure why? I was up high so no problems bringing her back to the field, it stalled about a foot of the runway at the last minute I decided to deploy the flaps, the CG got moved back just a tad when I installed the battery for the on board glow driver so on the glide it needed about two clicks of down elevator which I didn't have so she stalled on me and it landed on the wheels hard, I heard a !crack! it end up been the landing gear mounting rail from the right wing got loose and it cracked.

At the moment I have removed the balsa skin from around the rails and I'm preparing to re glue/repairs the mounting rails, I will do my special recipe on main gear mounting plate/rails once I do this then it is never to fail again.

RE: World Models Super Chipmunk 90
 

It looks like a rebuild is the only way I'll get this bird flying again. Every place I've checked has said they don't have the plans to cut the wings. Ithink I can get some expert help from folks in my club. I'll need help picking out material. I've briefly looked over the damage and I'll need a good model grade plywood and balsa. I believe I can do it with a little help and the right wing to use as a template.

RJ

RE: World Models Super Chipmunk 90
 

RJ
Give Bob O. a call, tell him Carlos gave you the site info. ask him if he can help you laser cut the ribs for that wing he will need the ribs and any other part with a shape ( his is right there in your back door )

LDS - Laser Design Services
1823 Emerald Bay Dr.
Rockwall, TX 75087
USA
972-772-4326



http://store.laser-design-services.com/

RE: World Models Super Chipmunk 90
 

Thanks Carlos. I really appeciate it. Rockwall is definately in the neighborhood.
I'll call him tomorrow.

Today was an excellent day for flying. After a couple of cups of coffee while checking my email, Iloaded up a couple of planes and headed for the field. Iarrived about 1:30PM and there were a dozen or so fellow pilots already there enjoying the great weather. It was a bit chilly when the sun went behind a cloud but, the winds were less than 10 mph all day. I had a wonderful time flying my Intruder 90R and my gas powered Reactor Bipe.

RJ

RE: World Models Super Chipmunk 90
 

I Started the main gear rails repairs, as suspected not enough glue on the rails and with the wood been burned by the laser the grains gets sealed and the glue doesn't get there at all, also the china ply is very brittle [:-] I new this had to happen it is a down side on the ARFs ( all of them )

Since the rail on the right main splitted in two I added a 1/16 ply piece under to reinforce it ( looking at the simplest way to fix it without reinventing the wheel :eek: ) I used 1/16 aircraft grade ply, 1/4" basswood, 3/32 carbon fiber rod ( instead of using wood nails ) 30 min epoxy, 5 min epoxy, thick CA/accelerator.

As you can see the basswood block use to stop the wire from rotating is now in a ply box to stop it from splitting because of a hard landing, the carbon fiber nails are in on a angle ( like 45 ) from the rail through the 1/4" basswood through the play and balsa ribs.

RE: World Models Super Chipmunk 90
 

RJ

You're welcome, I hope he can help with the wing [8D] It is nice that you guys are enjoying the Spring, we ( here in the SF bay area ) are still waiting :(

RE: World Models Super Chipmunk 90
 

After the rails I can't think of anything that could go wrong with this airplane, I will post a flight report after a few flights.

RE: World Models Super Chipmunk 90
 

It looks very strong. Should hold up fine.

RJ

RE: World Models Super Chipmunk 90
 

Thanks! I agreed :D

RE: World Models Super Chipmunk 90
 

Repairs are completed, will go flying on Sunday, too windy to day and tomorrow :eek: I will repair the wheel pants next week ( not much to do )

RE: World Models Super Chipmunk 90
 

My flights on Sunday were good, a little breezy but flyable, the engine ran fine this time and it was a joy to fly her, here is a pic with his little sister [&:] a bigger brother ( 30cc gas one ) will be on the way soon :D:D

This airplane has become one of my all times favorite one.

RE: World Models Super Chipmunk 90
 

Went flying yesterday, on the second flight my engine quit, it was low, mid runway, going up wind, needless to say it was not good to turn around for an up wind landing and no way I could do a left 180 to land down wind so, I went forward but she keep flying added flaps and she keep flying, finally she came down past the runway and then some, when she landed I could not see how she landed all I know is that I flew her all the way down to the ground and I imagine landing her.

I was very upset, I thought I had the engine dial in, as I was walking ( the walk of shame :eek: ) I could imagine the damage ( I was mad [:@][:@] )

To my surprise [X(][X(] she not only landed without any damage but a loose wheel pant, she had manage to avoid total destruction by landing about a foot or two past an 8 foot ditch [&:]

My conclusion was that the carburator was lean at the low end, after fixing the pant ( about three drops of thick CA ) the carb was adjusted and took her up for anothe flight, all went well with that flight so, my plane came home in two pieces ( as it should be :D:) )

RE: World Models Super Chipmunk 90
 

It's a scary thing when all goes silent. You have to keep your cool and fly the airplane all the way in ....just as you did. Great job and she lives to fly again.

Ref. you previous post ....looks like you'll have "Pa Pa bear, Momma bear, and baby bear. Where's Goldielocks. :)

Garry

RE: World Models Super Chipmunk 90
 

If your engine quits and you are in a position were coming back to the runway is nearly impossible then all your skills come out to play and this is the point were either you have it or you don't :( then again by a slim change you can get super lucky and walk away from it in one piece like me.

She lives to fly again.

Come on now, don't give me any more ideas, I'm already looking for papa bear :) regarding Goldilocks she should be coming along in the near future :D

RE: World Models Super Chipmunk 90
 

I came across a good practice habit that RC Heli pilots employ. The term they use is auto rotations, whereby they simulate or actually kill the engine and practice landing. I chop the throttle on all new birds and simulate dead-stick landings in order to get a feel for the new bird.

RE: World Models Super Chipmunk 90
 

That's excellent practice for all sizes and kinds of flying machines. Heli pilots do autorations and power plane pilots do (or should do) every landing with the engine(s)at idle to simulate engine out landings. Glider pilots have no choice. :)
When shooting landings during my full sized plane years, I attempted to make every landing an engine out simulation depending on where Iwas landing. When on final behind an airliner of any size is not the time or place but, at non "control tower"fields, it should always be done. Shoot a normal pattern approach and cut your power on down wind adjacent to your chosen touchdown point. It forces you to develop the judgement skills to save you plane while having the safety net of a running engine. If you can land it welll on a regular basis with the engine at idle you'll stand a much better chance of saving your plane in a real engine out emergency.
I've never had an engine fail in flight in a full sized plane but, I've sure had a few with RC birds and the practice came in VERYhandy.
Good advice.

Garry

RE: World Models Super Chipmunk 90
 

I had a World Models Chipmunk years ago with a OS91 Surpass. I kept this plane for years, longer than any plane in my 35 years of flying! My plane had retracts from the factory and
I wish that the new plane had them as well. I think that I may get a new one for every day flying. A great plane!

RE: World Models Super Chipmunk 90
 

Geneh
I picked up mine at the Airborne warehouse in Livermoore, the owner ( a very nice man ) said that they are not offering them with retracts any more because the need to have the axle of the wheels forward, in line with the wing leading adge. With the retact ones you can bend the forward but then you can't retract them back up.

I have noticed that having the wheels in the forward position gives the model a very stable handeling on the grownd, specially during landings.

The landings on this airplane are incredibly smooth and stable, once it rotates for the three wheel touch down it just continues in that attitude 'till it touches the runway.:D

RE: World Models Super Chipmunk 90
 

I haven't had time to fly my Chippy, kind of windy around here.

RJ
We're moving to Austin in summer, I'm sure I will be attending one or two events in the D/F area maybe we can meet then.

RE: World Models Super Chipmunk 90
 

Well, welcome to Texas. Be sure to give me a heads-up when you get the chance to come to the DFW area. There's plenty of RC activity here in the summer so you'll have plenty to choose from.

RJ

RE: World Models Super Chipmunk 90
 

ALL IS NOT LOST ! I found a new set of wings right here in my own backyard (so to speak). I was telling a fellow club member about my mishap with the Chipmunk and he said that he and his Dad were rebuilding a plane just like mine and had an extra set of wings. Imagine my joy in hearing that, especially when they said the would sell a pair to me. So, I should have it flying again soon. I'm very excited.

RJ

RE: World Models Super Chipmunk 90
 

I picked up the new wings last night at our club meeting and they are brand spanking new ....still in the bubble wrap along with a new fiberglass center section. Now, Ineed to install the control surfaces, servos, and gear and he will be ready to fly again.

RJ