Old ACE 4-40 Bipe -Help
 

Any and all help apprecaited

I am in the process of restoring the original ACE 4-40 Bipe recently acquired. Airframe is in great shape, however I just need a little help with incidences and CG.
My stab and lower wing are at 0. Is this correct? What should top wing be?

Also where is CG? At spar on lower wing?
any down thrust or right needed at motor?
What are good throws for controls?

Thinking about an OS 52 fs? Does it need more power?

RE: Old ACE 4-40 Bipe -Help
 

LJR:

Can't comment on cg, but the upper wing should be +2 incidence with the lower wing at zero.

Bill.

RE: Old ACE 4-40 Bipe -Help
 

The following specs are taken from Doc Matthews 4-40 Bipe as published in RCM 10-86, Plan #977. CG should be 2 9/16" back from the leading edge of the top wing. No down or right thrust on engine. Just set up zero/zero. Suggested surface deflections are: rudder 1/2" left and right, elevator 3/8" up and down, ailerons 5/16" up and down. The 4-40 is a sweet flying bipe. Enjoy!

RE: Old ACE 4-40 Bipe -Help
 

Does anyone have any comments on his engine choice? I'm also building one of these and am down to picking a power plant. The inside of the fuse at the engine is only 2 1/2" which barley allows for a .40 2 stroke + mount. The text in the instructions states that some prototypes were built with a .25 2 stroke and flew well - the .40 was for reserved for the wild - does anyone have any comments (from experience) about if a .25 would be way under powered and also if the .52 of LJR's above has any chance of fitting in the fuse? I will be getting a .46 recovered from a crash that I'm considering using but thinking it may be a waste of power.

RE: Old ACE 4-40 Bipe -Help
 

My 4-40 was powered with an OS40 Surpass swinging an 11x6 Master Airscrew prop and it was a perfect fit for the design. I am sure that one of the hotter 25s would fly it. However, a mild 2 stroke 40 would also work just as well. I'm not sure that you would want to put in a fire breathing 46 in it. With the right power package, it is a delight to fly.

RE: Old ACE 4-40 Bipe -Help
 

For those interested, a few construction pic's.

RE: Old ACE 4-40 Bipe -Help
 

First let me thank all the folks that replied. I'm now in much better shape.
Well, all the old monocoat is just about off , cabanes have been de-rusted. Next will be the tail wheel assembly and then the rest of the plane.
My motor choice is still tentative, however the seller had a K&B 40 sportsman in it and reports it flew very well .
The final motor decision will be based on weight , there is a lot of light ply & spruce in this plane. Right now , it has a HAYES motor mount (AS40)in it which is 1.33" between the beams and 2.11"overall width. So my thought of the OS 52 SF at 1.33 crank case width is more of a convience than anything else. A .40 four stroke would probably be fine too.
My felling is, if the plane RTF is 5 # then the .52 is perfect . If 4# then the .40 would be the ticket for bibe type flying. However a .25 two stroke sounds weak to me. Does anyone have the RTF wieght ( any motor).

LJR

RE: Old ACE 4-40 Bipe -Help
 

Hey LJR -

A friend's Ace 4-40 Bipe with standard servos/Rx and OS .48 Surpass four stroke came out at 5 pounds, 1.6 ounces (postal scale). It flew very well and was plenty fast enough with that engine.

Mike

RE: Old ACE 4-40 Bipe -Help
 

Thanks Mike-

You just saved us all alot of work.

LJR

RE: Old ACE 4-40 Bipe -Help
 

All the Ace 4- designs fly best when they are not overpowered. I'd go with the 40 4/stroke.

RE: Old ACE 4-40 Bipe -Help
 

question for the old ace 4 40 bipe kit.
Does it have dual alerions or just 2 on the bottom main wing.
If someone knows off the top of their head please speak up.
thanks
jake

RE: Old ACE 4-40 Bipe -Help
 

I am curious as to what is the wing area of this model?

RE: Old ACE 4-40 Bipe -Help
 

Ailerons are only on the bottom wing. I fly one most weekends. Sorry, but I can't answer the wing area question as I'm not sure I could find the plans.

Sotos

RE: Old ACE 4-40 Bipe -Help
 

LJR.To get the CG of that biplane just measure the distacne from the leading edge of the top wing to the trailing edge of the bottom wing.Multiply that by 25% and you have the CG if any wings are not swept back wich i don't think they are from the pictures posted.

RE: Old ACE 4-40 Bipe -Help
 

I have an old K&B .40 w/Perry carb in mine and it has plenty of power ... more than enough. It flies great but the old .40 sucks the miniscule 4 oz. tank dry REALLY fast.

Did any of you manage to put in a larger tank? I had no room with the thro servo up there.

I also put in a standard size servo for the ailerons instead of messing with anything else. I cut an opening in the bottom wing and built a hump cover for the servo where it poked through.

RE: Old ACE 4-40 Bipe -Help
 

Baz,

I managed to get a 6 oz tank completely inside the standard tank compartment, although it does but up against the firewall. Throttle servo is a mini, and is located in fuselage, above bottom wing.

HTH

Sotos