RCU Forums

RCU Forums (https://www.rcuniverse.com/forum/)
-   Scratch Building, Aircraft Design, 3D/CAD (https://www.rcuniverse.com/forum/scratch-building-aircraft-design-3d-cad-174/)
-   -   Lazy Ace Biplane build from coroplast (https://www.rcuniverse.com/forum/scratch-building-aircraft-design-3d-cad-174/11641617-lazy-ace-biplane-build-coroplast.html)

Joystick TX 03-19-2019 04:40 AM

It's close to 18 lbs right now.

The sink rate is deceptive in the video, the winds are pretty strong. It sinks at an angle of about two or three degrees with no headwinds. It's hard to get it to come down, it will fly with only two or three clicks of throttle.

Once the engine gets broken in, the prop will be changed from the 19x8 to a 20x8.

Propworn 03-19-2019 09:22 AM

Wow 18 lbs, mine weighs in just over 10 lbs maybe with the float on another 3 lbs YS 1.20 lots of power. I notice no difference with the lifting tail I even have a cradle that fits on the top wing and take up gliders. I have increased the rudder by 50% and the elevator the same. I had a few bad releases where the glider ended up hung up and near cross ways on the cradle and I was sill able to land the thing with full control. It is one of my favorites for sure. I really like the Telemaster as well also a lifting tail.

Dennis

Joystick TX 03-19-2019 12:48 PM

The lifting tail was not an issue at lower speeds. The lifting tail worked well with the narrow range of speeds possible with a glow engine. With a heavier plane and a 30cc to 40cc gas engine, the lifting tail created way too much down thrust which made the plane hard to control over a wide speed range due to the pitch changes. Going to a conventional tail and just using engine down thrust allows a wide speed range with no pitch changes or ballooning.

I also increased the rudder size to help control the plane better at low speeds.

Propworn 03-19-2019 04:35 PM

Couple of other Lazy Aces in the club that have gassers they are no faster than mine a 10 or 12 pitch prop at 7 to 8000 rpm is actually slower than an 8 pitch prop at 10,000. They all have the original lifting tail no adverse effects. If speed was a problem then my vertical dive to landing should show a marked tucking under as I come straight down from altitude after releasing a glider so I can take the next one up. My speed in a dive far exceeds anything I have seen a Lazy Ace do on the flat and level.

I even had one set up as a Triplane with 3 OS .61s it would drag the thing straight up from a short roll but wasn't much faster and far less fun then the lighter single engine.

Joystick TX 03-19-2019 07:06 PM

All I can say is that mine started to dive at WOT. It was not stable in pitch over the entire speed envelope.

With a symmetrical airfoil on the stab and engine down thrust, it is now stable at all speeds and does not balloon when the throttle is chopped.

I'm not saying that my plane is faster than your plane, or any of the others, just that the lifting tail does not work correctly on mine over my speed range.

Propworn 03-20-2019 06:11 AM

Could it possibly have something to do with removing the stagger or any of the other changes you made. Not criticizing just trying to understand why yours displays a tendency to tuck at speed when none of the 3 or four I have flown have no such tendency. Power shouldn't be an issue one had a Supertiger .65, YS 1.20, 32cc gas motor and the tri motor.

The heaviest I have flown mine is with the ashes of a departed friend to be spread over the flying field somewhere around 17 lbs. I did not know the cremated remains could weigh as much as 6 or 7 lbs and this was with that weight 6 inches above the top wing. No adverse flying characteristics.

Dennis

Joystick TX 03-20-2019 06:40 AM

It could be a number of things. I had to remove the wing stagger or add about three pounds to the nose in order to get the plane to balance correctly. I also have -3 degrees incidence in the top wing to make sure it stalls after the lower wing. There are a lot of tradeoffs in aeronautics.

The plane is about 1 oz tail heavy right now since I added the 40cc twin. The engine is a little heavier than the 35cc and the standoffs are a little shorter, but the two changes did not cancel out exactly. It is not enough difference to cause any flying issues.

Joystick TX 04-07-2019 06:35 AM

Had to do an emergency repair at the field. One of my tail-wheel springs broke and I didn't have a spare.

This actually gives me better control in the grass.

https://cimg4.ibsrv.net/gimg/www.rcu...672be82ab3.jpg
Yes, there is a heavy duty servo with metal gears, so it should hold up pretty well. Even if it does fail, there is a good chance it will be on the ground.

Joystick TX 06-15-2019 06:56 AM

I became a little nervous having only one LiFe battery for the receiver, so I put in two 1,100 mA LiFe batteries to provide redundancy.

I never had any problems, but several planes have been lost due to LiFe battery failures at our field.

Have 211 flights, 10 min. each, so far and this is still my favorite plane.

Joystick TX 08-20-2019 01:26 PM

My DLE 40 Twin engine has not had good compression from the start. It did pick up a little but not nearly as much as the DLE 35 that I took off the plane at flt #150. I had a total of 248 flights on the plane today. I decided that with 16 hours of run time on this engine, it isn't getting any better.

I had a Bowman ring for a DLE 20 from a couple of years ago that I never put on an engine, so I just got a second ring and put them on today. The compression is way better already and I haven't even run the engine.

One thing I noticed during the ring swap was that the right cylinder had a lot of carbon on it and none on the left.

Can't wait to see how it runs when the weather cools off a little.

Joystick TX 08-20-2019 05:11 PM

I couldn't wait for the weather to cool off. It did get down to 103, so I gave the rings a 5 min break in time and put one 10 min flight on the plane.

It has way more power than it did this morning before the ring change. It was about 87 degrees when I flew at sunup and I couldn't get good vertical performance. This afternoon I had unlimited vertical at 103 degrees. The hesitation on takeoff at the midrange transition was also gone.

When I replaced the rings, I set the needles back to the factory setting and didn't adjust them yet, so the engine is probably running a tad rich.

Love the new rings.

Joystick TX 09-02-2019 04:40 AM

It took a while, but the plane is finally featured in Focal Point of the September issue of Model Aviation News. It may encourage others to build big planes out of coroplast.

It now has 253 flights on it, that's over 42 hours of flight time, and it's still my favorite plane to fly.

I realized there were no pictures of the plane with the 40cc Twin engine.https://cimg5.ibsrv.net/gimg/www.rcu...42f7fcc719.jpg

Joystick TX 01-07-2020 01:47 PM

Flew today with one wing.
 
Today on 10 min. flight number 307, I flew the LA with the top wing removed.

https://cimg0.ibsrv.net/gimg/www.rcu...b074899172.jpg
It flew great. It was hard to tell the difference between flying with or without the wing. I did notice that it did land a little faster, maybe 2 or 3 mph. There was no difference in the slow speed flight, the plane still does not stall, it just mushes and slowly loses altitude.


Joystick TX 01-14-2020 08:15 PM

I finally got around to making the cutouts for the new engine on the old cowl.
https://cimg9.ibsrv.net/gimg/www.rcu...600f42a59e.jpg

Joystick TX 01-22-2020 10:33 AM

Since the plane flew well as a low-wing monoplane, I decided to add some ailerons to the top wing so I can fly it as a parasol wing type plane. It shouldn't require any trim or balance changes in that configuration either.
https://cimg3.ibsrv.net/gimg/www.rcu...9f57c5b639.jpg


Joystick TX 01-24-2020 05:18 PM

Finished the ailerons and flew a couple of flights this morning. Roll is a little faster, didn't notice any other differences.

Now that there are ailerons on the top wing it's time to try the plane in the Parasol wing configuration. Weather permitting that will be done tomorrow morning.
https://cimg8.ibsrv.net/gimg/www.rcu...f8f566bba2.jpg
https://cimg9.ibsrv.net/gimg/www.rcu...675cf67bd5.jpg

Joystick TX 01-25-2020 01:45 PM

I flew it twice as a parasol winged plane. Flights 317 and 318. It flies great, it did take a lot of up-trim since the wing incidence is set at -3 degrees. Landing speed was a little faster than the low-wing style, due to the wing incidence, it is a little harder to get it to flare correctly.

I'm going to put a "3 N 1" decal on it. Biplane, Low-Wing Monoplane and Parasol-wing Monoplane.

Joystick TX 10-17-2020 04:55 PM

I changed the bomb mechanism to mate up with a lot larger bomb, I call it the RBB, Really Big Bomb. It's made from Coroplast too, with half of a Nerf football in the nose. The little green bomb was hard to find in the grass.

Dropped it on 10 minute flight number 491. Flying has slowed down a bit this year due to the covid issue.

The plane is still doing well. I'm going to build another one from Coroplast. It will be a mid-wing monoplane with an 8 foot wingspan. I'll power it with the DLE-35ra that I took off this plane.
https://cimg5.ibsrv.net/gimg/www.rcu...a4fe882d77.jpg

sensei 10-19-2020 03:39 AM


Originally Posted by Joystick TX (Post 12574509)
Today on 10 min. flight number 307, I flew the LA with the top wing removed.

https://cimg0.ibsrv.net/gimg/www.rcu...b074899172.jpg
It flew great. It was hard to tell the difference between flying with or without the wing. I did notice that it did land a little faster, maybe 2 or 3 mph. There was no difference in the slow speed flight, the plane still does not stall, it just mushes and slowly loses altitude.

So you doubled the wing loading and didn’t notice much difference?

Bob

Joystick TX 10-19-2020 03:47 AM

No, I was shocked. I thought it would be very noticeable. The climb is a little better, only the glide seems to suffer.

It didn't quite double the wing loading though, the wings weigh over 3 lbs so the weight went from around 18 to 15 pounds.

sensei 10-19-2020 05:40 AM

Is yours the 76” or the bigger one, looks like the 76” in the pictures.

Bob

Joystick TX 10-19-2020 06:34 AM

It's actually 72" because I used yardsticks for the wing spars.

Joystick TX 11-12-2020 11:25 AM

I did some camera work today trying to find a plane that my buddy lost. The pictures are of the field this morning one just flying around and the other one coming in for a landing, there was zero wind and the temp was only 55 degrees, not bad for mid-November.

Got in one more flight this morning to make it flight number 500. The plane is still doing well and it's still my favorite.

I'm working on another coroplast plane now, it will have the same basic fuselage as this one, but it will be a mid-wing design and will be powered by my old DLE-35ra. It will be in the 12 to 13 lb range.
https://cimg4.ibsrv.net/gimg/www.rcu...b3613164c.jpeg
https://cimg0.ibsrv.net/gimg/www.rcu...c3d9152b3.jpeg

Joystick TX 12-18-2020 02:35 PM

I finished the other coroplast build. Details are on this site, you can search for New Dog, or follow the link at: https://www.rcuniverse.com/forum/scr...coroplast.html

I don't like flying the LA Bipe in crosswinds, the new plane should be easier to handle in them.


biggy boy 05-15-2022 12:14 PM


Originally Posted by Joystick TX (Post 12651200)
I finished the other coroplast build. Details are on this site, you can search for New Dog, or follow the link at: https://www.rcuniverse.com/forum/scr...coroplast.html

I don't like flying the LA Bipe in crosswinds, the new plane should be easier to handle in them.

I just picked up a 76 inch Lazy Ace covered in Koverall never flown, figure it’s about10-11 years old.
no engine,so I’ve put a 31cc twin gasoline engine on it.
will fly it soon.

I also have a 1/4 scale cub made with 4mm and 2mm coroplast with a 26cc
with a 110 much wing span.

do you think it’s worth while putting the ailerons on the upper wing of the Ace?

Glen

https://cimg4.ibsrv.net/gimg/www.rcu...43583f0f5.jpeg
https://cimg7.ibsrv.net/gimg/www.rcu...589c92cb2.jpeg
https://cimg8.ibsrv.net/gimg/www.rcu...39078805a.jpeg
https://cimg9.ibsrv.net/gimg/www.rcu...90ca24a4f.jpeg
In the test stand for breakin


All times are GMT -8. The time now is 12:08 AM.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.