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Breezy wings...

Posted By:
David Cronkrite
Homebuilder or Craftsman
15
Posts
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#1 Posted: 12/8/2009 07:58:18


Hello all.  I am gathering information in preparation for building an RLU-1 Breezy ( http://www.eaa.org/homebuilders/kitplans/breezy.asp ).  The Breezy was designed to accept a pair of PA-12 wings, however, it will also take PA-14, PA-18, or J-3, J-4, or J-5, and possibly many others.  And, since there are no wing plans with the Breezy plans, I must choose one. 

Currently, I am wing stupid.  I know the above are Piper wings, but what are the differences between them?  Is there a definitive "wing guide?"  I am a well-experienced fabricator, but a first-time homebuilder; which is going to be the best for a beginner?

Other considerations: I live in Deep East Texas and I suspect she will see many a short, grass runway.  She will be hangared in my shop, and I will have to trailer her several miles to fly, so, removable, caddy-able wings are a must.  Cost is also a factor; I will spend whatever it takes, but the less Ramen I have to eat, the better.  

Also, I have not found anywhere to purchase wing plans separately. 

Any input would be greatly appreciated. 

Thanks in advance,

--Dave




If God had intended for man to fly he would have given him a keen mind and the desire to do so. Oh, wait...
Ron Wanttaja
246
Posts
98
#2 Posted: 12/8/2009 11:28:33
David Cronkrite wrote:

 


Hello all.  I am gathering information in preparation for building an RLU-1 Breezy ( http://www.eaa.org/homebuilders/kitplans/breezy.asp ).  The Breezy was designed to accept a pair of PA-12 wings, however, it will also take PA-14, PA-18, or J-3, J-4, or J-5, and possibly many others.  And, since there are no wing plans with the Breezy plans, I must choose one. 

Currently, I am wing stupid.  I know the above are Piper wings, but what are the differences between them?  Is there a definitive "wing guide?"  I am a well-experienced fabricator, but a first-time homebuilder; which is going to be the best for a beginner?

Budd Davisson has a good article on the differences between Cub models.  For the most part, it looks like the wings are pretty much the same, except when it comes to the Long Wing/Short Wing models. 

Like other early homebuilts (such as the Fly Baby), the Breezy was designed to use what was then "common" spare Cub parts that could be obtained cheaply.  These components aren't so common, now.

But as for scratch-building Piper wings, you're in luck:  Wag-Aero sells plans and kits for its J-3 replica, the "Sport Trainer ".  Plans are only $125.  These should work fine on a Breezy.

 

 



Ron Wanttaja
Joe Norris
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#3 Posted: 12/8/2009 16:50:29

When comparing Piper "Cub" wings, the first thing to know is that the airfoil shape is the same for all of them.  All Cub variants (long wing and short wing) use the USA-35B airfoil, so the plane will fly pretty much the same regardless of which wing you use.

Having said that, the big difference you'll find is the aileron system.  The PA-12 and PA-14 wing (as well as the J4 and J5) have a completely different aileron control system as compared to the J3, PA-11 and PA-18 (and all the short wing Pipers as well).  The J5/PA-12 system employs a bellcrank to control the aileron and all cables are internal in the wing.  Other Cub wings do not employ this bellcrank, and instead the aileron cables attach directly to control horns on the ailerons.

The only effect this would have on your project is that you'd have to route your cables according to whatever wing you decide to use.  While there is a noticeable difference in the "feel" of the two systems, the flying qualities of the wing are virtually identical.

As for procuring the wings, you could easily build up some Cub wings from Wag-Aero plans rather than finding a set of Piper-produced wings.  This would also give you the added benefit of getting even more credit toward the "51% rule" for yourself as compared to using salvaged Piper wings for which you will receive no construction credit even if you completely rebuild them.



Lasciate ogne speranza, voi ch'intrate
Andy Gamache
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#4 Posted: 12/9/2009 03:00:17

Hi Dave,

 

This subject has been discussed a lot on the Breezy Yahoo group.



David Cronkrite
Homebuilder or Craftsman
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#5 Posted: 12/9/2009 06:41:32

Great article!  Thanks, Ron.  I've always liked the Piper Cub, but didn't know there were so many versions. 



If God had intended for man to fly he would have given him a keen mind and the desire to do so. Oh, wait...
David Cronkrite
Homebuilder or Craftsman
15
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3
#6 Posted: 12/9/2009 06:44:03

Excellent info.  Thanks, Joe.  Just the sort of stuff I was looking for.  I'm going to go ahead and get the Wag-Aero plans and might just make it project number two.  I've always wanted a Cub, anyway.  A replica will do.

Can you recommend a book or other publication on building wood and fabric wings?



If God had intended for man to fly he would have given him a keen mind and the desire to do so. Oh, wait...
David Cronkrite
Homebuilder or Craftsman
15
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3
#7 Posted: 12/9/2009 06:44:26

Ah, a Yahoo! group.  I didn't think to look there.  Thanks, Andy!



If God had intended for man to fly he would have given him a keen mind and the desire to do so. Oh, wait...
Ed More
Young Eagles Pilot or VolunteerHomebuilder or CraftsmanAirVenture Volunteer
10
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#8 Posted: 12/19/2009 17:13:13

Hello Dave,

Just a few comments.

The Cub ribs were made from built up sections of thin aluminium strip stock roll formed into T sections etc. and assembled with tiny rivets. This is very light, but time and tool expensive. Aeronca ribs were hydroformed aluminium sheet blanks and required intermediate forming and annealing, also tool expensive but less cost with a fair amount of scrap. Wood ribs are time expensive if built up from sticks and gussets which are also light. The Fly Baby ribs were quick and with little scrap. Basicly, they had sawn cap strips from fir and band sawed plywood fillers with no lightening holes forming an "I" section. They are heavier than Cub or Aeronca ribs but very strong and very easily built. In fact, the bottom capstrips were first glued to the nose rib and the webs leaving two spaces for the spars. The spars were then threaded into the slots with the ribs in position and the top cap strips added afterwards. This assembles the ribs and wing panel at the same time and saves enormous amounts of work. The USA 35B wing section also used on the Fly Baby, has a flat bottom and this works very well for good alignment and true surfaces. Peter Bowers simply glued the fabric to the cap strips which were 5/8 ths inch wide. This works very well but make sure the wood is sealed with a varnish compatible with the fabric adhesive.  Drag and anti drag wires were accomodated simply by putting a saw slot into the web at the right locations and the wires put in place before adding the top cap strips. You might want to consider some Fly Baby plans which appeared in the magazine back in the sixties and were much less cost than the WagAbond plans. I used spruce and an industrial grade of plywood from Harbor Freight which was more than adequate and quite inexpensive. The Fly Baby method has very little waste and is strong "like bull".

The Ritz method is pretty good and lighter in wood. Jerry used three laminations of wood glued up on an upper airfoil curved surface. He then chordwise band sawed to generate upper cap strip width to generate upper cap strips and milled a chordwise slot in the under surface of the cap strip.  Since it is also a flat bottom airfoil the lower cap strips were simply square cross sections of solid wood with a similar chordwise inner slot. Plywood forms closed the cap strips lead and trail by gluing them in the saw slots in the cap strips. This was done in a nail jig. While the assembly was in the jig, Wood strips milled to the slot width were used to add diagonal bracing and verticles to attach to the spars. Aileron ribs were trimmed off of the  full rib assembly. This produces very inexpensive and light ribs with very little waste. Fabric can be glued or stitched to these ribs.

The WagAbond used traditional stick and gusset ribs. I have a set of WagAbond plans you could have for half price plus shipping. If you want to see a picture of the Ritz rib construction, e-mail me back and I'll reply. If it were my project and I was going for cost and weight, I would use the Ritz method. It is both light and strong, but you would have to laminate some upper capstrip material which means a form and a method of applying pressure for the laminating. The Fly Baby is the quickest and heaviest, the stick and gusset is the lightest but most time consuming, and the Ritz is a mixrure of the two but almost as light as the stick and gusset and a lot less work. Don't forget that the stick and gusset has to be removed from the jig and gussets applied to the other side. The Ritz avoids this entirely and the rib is ready to use straight from the jig. The Fly Baby avoids use of a jig entirely but is the heaviest. "Ya pays your time and takes yer cherce." as they say in Jersey.   Ed More LT 18475



EdM from NH
Jim Hann
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#9 Posted: 12/19/2009 18:52:58

A couple of comments from a guy who is hoping to build a Fly Baby off shoot.  The airfoil on the 'Baby is the NACA 4412, modified with a flat bottom by drawing a straight line from the lowest ordinate on the bottom straight back to the TE.  Another rib style is the Les Long type, It is outlined in the EAA wood book.  All spruce stock with double capstrips and the verticals sandwiched in between.  Light and simple, takes a little longer than the solid rib but weighs less than even a gusseted rib, according to the book.  Just a thought.

Jim



http://sites.google.com/site/jimscavaliersa1025/ http://picasaweb.google.com/CozyCanard http://sites.google.com/site/cavalieraircraft/
David Cronkrite
Homebuilder or Craftsman
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#10 Posted: 12/21/2009 12:47:02 Modified: 12/30/2009 20:08:05

Hi Ed,

Thanks for your comments; you're speaking my language, and ,yes, I would love to see those photos of the Ritz method.

I would also like those WagAbond plans, and as soon as I have recovered from the Christmas Crunch Cash Crisis, I will be sending a check.  Give me a total and I will email when I send the check.  And, thank you for such a generous offer.

I have a question or two.  Are the WagAbond wings the same as the Sporttrainer?  I would think that they are, knowing the way most manufacturers do things, and in the photos on Wag Aero's website the WagAbond LOOKS the same, but is missing the jury struts that I see on all their others.

When laminating the capstrip stock using the Ritz method, what sort of pressures are we talking?  Sandbag and brick, or hydraulic press?

Thanks again,

 

--Dave

 

 



If God had intended for man to fly he would have given him a keen mind and the desire to do so. Oh, wait...
David Cronkrite
Homebuilder or Craftsman
15
Posts
3
#11 Posted: 12/21/2009 12:54:47

Thanks for the thought, Jim.  Now, I can look up the Les Long method.

--Dave

 



If God had intended for man to fly he would have given him a keen mind and the desire to do so. Oh, wait...
David Cronkrite
Homebuilder or Craftsman
15
Posts
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#12 Posted: 12/30/2009 20:05:35

Ah, I see.  The WagAbond wings are NOT the same since it is a PA-15 replica, which is a short wing Cub.

 You guys opened the refrigerator door, it just took a while for the dumb newbie's light to go on. 

 I know I have a lot to learn.

--Dave the Dumb Newbie

 



If God had intended for man to fly he would have given him a keen mind and the desire to do so. Oh, wait...
Arnold Zimmerman
1
Post
1
#13 Posted: 1/12/2010 07:20:15

Hello Dave,

I can highly reccomend a Piper cub wing with Cub tail surfaces and a Lycoming 0-235 !! I have been flying Breezy's for 33 years with over 6,500 hours PIC and 2,000 in Breezy's. My first Breezy had Cub wings rotated at 45 mph and cruised at 65 mph and would carry a good load. Present one has Citabria wings, rotates at 55mph cruise 75 mph and is a hot rod. You may have seen me at Air Venture as I have been giving free rides on the flight line for the last 20 years. By the way, the picture that is on your posts is my Breezy N3AZ !!!

Sincerely

Arnie Zimmerman

Breezy N3AZ                                                                                                                                                                                          



David Cronkrite
Homebuilder or Craftsman
15
Posts
3
#14 Posted: 1/12/2010 09:46:00

Hi Arnie!

    After much reading and many questions, I am indeed leaning towards the J-3 Cub wing and tail feathers.  The Lycoming power plant may be a tad out of my price range, but I am years away from that point, and who knows what will come?  Your opinion certainly carries a lot of weight as I am well familiar with your N3AZ Breezy, and chose it as my avatar on purpose.  See, you are my hero.  Anyone who would paint up their Breezy like an old war bird and brandish toy rockets is a man after my own heart.  I hope to make my first Air Venture this year and maybe meet you face to face.  If you are giving rides this year, I will be in line.

--Dave

 



If God had intended for man to fly he would have given him a keen mind and the desire to do so. Oh, wait...
Theodore Fails
Homebuilder or Craftsman
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#15 Posted: 1/18/2010 14:08:12

One question.  Anyone know why the USA-35B is nearly unique in airfoil sections in that the abscissa of the trailing edge is not zero?  This makes comparing the USA-35B with other airfoils a tad funky.