ka6yrc

I was recently given a Corben Super Ace that a friend could not get to fly well.

The first thing that I noticed was that the wing and horizontal stab were way off with the wing requiring the trailing edge to be raised about 1" to achieve 0/0 incidence.

The plane has an 80" wing and I am using a Super Tiger 90 engine. The wing chord is 14".

I have guestimated the cg at about 4" back from the leading edge of the wing.

In flight, the plane is very sensitive on the controls and wants to imediately climb if power is applied.

Any information or suggestions would be appreciated.

Norm

big max 1935

My Feedback: (9)

The sensitive controls sound like too much travel ,too quick or tail heavy . As far as climbing under power is common with a flat bottom wing, try increased down thrust. Quite an incidence change , be nice to find the plans & check them . MAX H.

ka6yrc

Big Max,

Thanks for the coments on my question. I plan to tone down the control throws quite a bit and I thought that some down thrust would help the climbing problem. I'm glad to hear that someone else agrees with me.

Ed

Down thrust, and get the CG up around 3 3/8 - 3 1/2" from leading edge.

ka6yrc

Now that I have gotten some good suggestions on how to adjust my Corben Ace, can anyone tell me anything about this plane? (Full size or the model)

big max 1935

My Feedback: (9)

I would bet yours was built from magazine plans as the only kit I remember was a VK in the mid 70's, 40 to 50 size engine . Seems if there was a Baby Ace, a parasol with the plans & magazine article in Mechanics Illustrated in the late 40's or 50's. May be some one has the VK plans , size would make no difference as to CG or incidence. Try Vintage & Antique Forum , that's where a lot of old poops hang out. MAX H.

r1morris

My Feedback: (1)

1952 Machanix Illistrated Baby Ace.
Found an old mag with some plans so I made this little 40 inch electric Baby Ace . The wing on the baby ace was a cub wing by the way so the CG is the same as a cub.

ka6yrc

Thanks to everyone who helped with ideas on my Corben Ace.

A search of the internet brought up some very interesting information.

The original Corben Super Ace was designed by Orland G. "Ace" Corben around 1935.

Corben began building "kit" airplanes in 1923 establishing him as the founder to the homebuilt aircraft movement.

Prior to the Super Ace he designed the Baby Ace and the Junior Ace.

The model Super Ace is kitted by Ikon N'West up in Idaho and I'm waiting for some info from them to get the plane trimmed out.

Information on Corben came from an article in "Air Currents" which is published by the Dane County Airport in Madison, WI.

P. Winters

My Feedback: (243)

Norm,

I wanted to ask about your Corben Super Ace. I realize that this post is several years old, but I'm wondering if you ever found out who made your kit. I just acquired a fully built Corben Super Ace with the same 80" wing. I don't have any info, manual, plans, etc. Anything to share with me?

Thanks,

Patrick

Crash Campbell

Hi Patrick,

This may help with the C of G.

http://www.inlandsloperebels.com/Calc/cgcalc.html

Cheers,

Colin

P. Winters

My Feedback: (243)

Thanks Colin!

flyingvranch

I just recently finished a Baby Ace. It was a Corbin design basically the same as the Super Ace. I scratched most of the airframe using old Model Builder magazine plans. It has 82 inch wing with 13 3/4 inch chord and the cg is 4 3/8 back from the leading edge. It took a ton of down thrust for the 26 cc gas engine. It weighs in at 13 lbs. Plane flies great now and is a real sweetheart. Pics attached. Hope this helps!

Stickbuilder

Yours is probably one of Emil Neeley's Ikon N'West kits. These were not very good kits, but if you used the provided parts as templates, and selected your own wood, then they went together fairly well. The plan was a blue line drawing, without much of any detail, and You had to use your own imagination to build the kit. The instruction sheet was just that. One sheet of paper, with some vague ideas of how to build the model.

I have one of these that was built about 15 years ago, and it's covered with Sig Koverall and finished with dope. Mine has most of the scale detailing and flys fairly well. The model exhibits a pronounced, "Dutch roll" when under power, and after reading the Polular Aviation magazine article from 1934 and the subsequent issues that covered their build of this airplane, it appears that the original full scale planes had this same problem. The full scale planes used a modified Ford Model A engine for power. I have quite a few photos of mine during the build, and here is a picture of the completed model.

These have never done very well at a scale contest. They were not, and probably will never be very popular, because of the simple lines of the model, and due to the fact that they are not very pretty once completed.

They are a chore to build, and engine cooling is also a problem. I had to build in a cooling tunnel to get the air out of the tight cowl. This requires using some 1/64th ply to shape the hot air exhaust back and down to the bottom of the fuselage in the radiator area.

Let me know if you need other information on this one. Mine is an 80 1/4" wingspan, and with the Saito .80 engine and all the radio gear, the model came in at 10 pounds, 6 ounces.

The incidences on mine are 0, wing to datum line, and +1 on the horizontal stab. I don't use any down or right thrust for the engine, since I fly using the rudder, rather than allow the plane to fly itself. Ground handling is okay, but you would need to see my steerable tailwheel linkages to believe it. I'll measure the C/G for you tonight, and post that. The real problem is the shape of the fuselage, and small vertical stabilizer/rudder. The V. Stab does not see much air on this one.

Bill, Waco Brother #1

Stickbuilder

The Center of Balance (I hate the term center of gravity, since gravity is constant over the entire airframe) is 3 7/8" behind the leading edge at the fuselage.

Bill, Waco Brother #1

buzzard bait

By raising the trailing edge of the wing one inch you probably wiped out whatever downthrust it may have had; in fact, you might now have upthrust.

The relevant thrust line is found by comparison with the incidence of the wing, not the fuselage datum line (which has no aerodynamic significance). At a given speed, the wing has to fly at a certain angle of incidence for level flight. Raising the trailing edge is the same thing, in flight, as tipping up the nose, and therefore the thrustline.

The effect of the stab is adjusted by trimming the elevator, so if the wing has too much incidence relative to the stab, the solution is to add down trim. Of course, it would be even better to raise the leading edge of the stab, but that is often not an easy thing to do on a model.

With the trailing edge of the wing raised, your elevator trim looks more normal, which is why a lot of people do that on vintage designs. The problem is that when you add power the thrust line in flight causes the plane to climb. In other words, the loss of downthrust means that the trim difference between low power and high power is greater.

Jim