Notices
Scratch Building, Aircraft Design, 3D/CAD If you are starting/building a project from scratch or want to discuss design, CAD or even share 3D design images this is the place. Q&A's.

Monocoupe 90-A 53" wingspan

Old 05-29-2008, 10:29 AM
  #1  
SharpProp
Senior Member
Thread Starter
 
Join Date: Dec 2007
Location: Dorchester, IL
Posts: 307
Likes: 0
Received 0 Likes on 0 Posts
Default Monocoupe 90-A 53" wingspan

I really like this model and I have found some plans online. My only other experience in building is a small at-6 Texan which is still in the works. I was wondering if anyone has experience with this size of a monocoupe. I'm pretty confident that I could build it but just not sure if their are some little surprises in there that may require more experience. Also does anybody have a four stroke engine recommendation for this size plane ( 53' wingspan is all I know about the specs of it). Thanks
Old 05-29-2008, 12:35 PM
  #2  
Campy
Senior Member
My Feedback: (1)
 
Campy's Avatar
 
Join Date: Jan 2002
Location: Baltic, CT
Posts: 3,613
Likes: 0
Received 1 Like on 1 Post
Default RE: Monocoupe 90-A 53" wingspan


ORIGINAL: SharpProp

I really like this model and I have found some plans online. My only other experience in building is a small at-6 Texan which is still in the works. I was wondering if anyone has experience with this size of a monocoupe. I'm pretty confident that I could build it but just not sure if their are some little surprises in there that may require more experience. Also does anybody have a four stroke engine recommendation for this size plane ( 53' wingspan is all I know about the specs of it). Thanks

I built a 55" span Monocoupe 90 from plans. http://www.vintagercplans.com/order5.htm (they also offer an ABS cowl and wheel pants). The plans called for a 35 2 stroke engine. For a 4 stroke I suggest something in the "30" size for plenty of power. (you would probably find a 26 is more than enough if you keep the plane lite.

I did mine up as an electric using a TowerPro 3520 motor, 60 amp ESC and a 4S lipo with BlueBird BMS 380 MG servos (http://www.bphobbies.com/). Do not get the nylon gear servos - the gears strip easily.

I get very good performance from this setup - fast speed (when I want it) and plenty of power to loop from level flight and other aerobatics.

Hope this helps.
Old 05-29-2008, 12:45 PM
  #3  
SharpProp
Senior Member
Thread Starter
 
Join Date: Dec 2007
Location: Dorchester, IL
Posts: 307
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Monocoupe 90-A 53" wingspan

oops my wingspan was off.....that's the exact website I'm thinking about getting the plans from. I'm surprised about how little engine it requires. I assumed that the fuse would be a little bulky and require about a .50 2 stroke . Were the plans easy to work from?
Old 05-31-2008, 09:33 AM
  #4  
Campy
Senior Member
My Feedback: (1)
 
Campy's Avatar
 
Join Date: Jan 2002
Location: Baltic, CT
Posts: 3,613
Likes: 0
Received 1 Like on 1 Post
Default RE: Monocoupe 90-A 53" wingspan

I found the plans easy to work from. The fuselage is "stick built". The best way to get both sides the same is to build the 1st side over the plans, then put a piece of Saran wrap over that side and build the 2nd side right on top of the 1st side. The plans show a rubber band hold down for the wing. I modified mine and use 4 nylon bolts to hold the wing on. I used K&S streamline tubing for the struts with a hard balsa plug to connect the upper an lower part of the struts together. The lower part of the strut is epoxyed to the fuselage (re-enforce the inside of the fuse in this area with some 1/8" balsa) and the fuselage fillet is made from "Bondo" mixed with some micro-balloons then sanded to shape.

Be aware that

1. This is a "short nose, long tail" type of plane. That means keep EVERYTHING aft of the firewall as lite as possible, and even with that, you will probably need to add nose weight to get it to balance. I don't know what brand of engine is shown on the plans, but IT IS THE SHORTEST ENGINE I HAVE EVER SEEN.

2. If you are going to use glow power you will need to modify the firewall called out in the plans and scratch a new firewall for mounting the engine about 1/2 way between the original firewall and the windshield. The original firewall will need to have a U shaped slot cut in it so that the engine can sit in the U. The other option is to lengthen the nose of the plane (that will destroy the scale outline though).

The first build I did I put an OS 46FX in it. I also had to add 8 oz - 9 oz of lead to the inside of the cowl to get it to balance. The OS 46 FX was WAY TOO MUCH POWER for the plane (I had unlimited vertical at 2/3 - 3/4 throttle, plus I was afraid to use full throttle). This is why I went electric. I bought a long skinny lipo and cut a hole under the motor so I could slide the lipo forward. My lipo sits even with the front of the cowl. I had to add 1 oz of weight to the inside of the cowl to get it to balance. The TowerPro 3520 is even too much power. A 28mm motor will have plenty of power for the plane although you would probably need to add more nose weight with that motor. In the electric configuration mine weighs in @ 4 lbs 4 oz ready to fly.

Incidence is not shown/called out on the plans. I set mine at 0 on the main wing and 0 on the horizontal stab. She comes off the ground in about 3' - 5' at 2/3 throttle, but flys fine. I suggest keeping a little power on for landing (I cut the power just as the mains touch and start feeding in up elevator to plant the tail) and try to make your landings "3 point" to avoid nose overs (especially if you fly off a grass runway).

Hope this helps.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

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