Berkeley B 26(A-26) build
 

Hey folks!
I just recieved a set of Berkley B 26 plans. I'm thinking about building it as a starter for getting into the twins before I build my B 17. What can ya'll tell me about the plane? I might start the build here in a day or so, but I haven't even looked at the plans that much. I'm an experienced builder, but I've never done a twin. Does anyone have one of these planes still? Any help is appreciated.



50%

RE: Berkley B 26
 

MAN, that's an antique!!! Was it orginally designed for U-Control?

RE: Berkley B 26
 

It's RC and CL.(or that's what it says on the plans) I will have to modify it for moddern RC use. The plans only have a few of the ribs for the wing and stab. Does anyone have a full set, or does anyone know the airfoil(s)? The fuse should be easy to build. I think I could have it framed in an hour or two, but I will be modifying it to attach the wing with nylon screws as rubberbands are a pain.

50%

RE: Berkley B 26
 

Chris:

Is your "B-26" the Martin "Marauder" or the Douglas "Invader" that was originally designated the A-26?

If it’s the Douglas you shouldn’t have much problem beyond the tendency of all the Berkeley plans to build heavy.

If it’s the Martin you are getting into a nest of vipers. The “Real” plane had an extremely high wing loading, a scale plane on U-control would fly pretty well in spite of the high wing loading but an R/C model is a lot less forgiving. Since you’re going to have to cut all the parts anyway add at least one extra bay to the wing, increasing the span, I would also increase the chord by 15 to 20%. And put about 4 degrees wash out in the wing to smooth the stall.

The Martin is so seldom modeled that few (if any) will notice the larger wing, it will still be too close in appearance for anyone but a scale judge to be sure.
And it could well save your butt.

Bill.

RE: Berkley B 26
 

This is the Douglas Invader. I know how to build light. I'm more into 3D type "scale aerobatics" so lightening shouldn't be a problem. I just don't want to go to light as a B 26 shouldn't be a kite. Do you(or anyone) have any pics? How heavy do they build and how much weight should I take off? 10 pounds wouldn't be out of the question, but I was sortta wanting to sheet it to do rivets. I don't have a scheme yet, but I want to use a B 26 scheme.(as opposed to A 26) Does anyone know where I can get a foam wing or the full set of rib templates?


Thanks,
50%

RE: Berkley B 26
 

Chris:

I have several pictures of variant Douglas A/B-26 planes, three here, and one scale model.

The first of these two is the B-26K as sent to the Congo in 1965, the second one, even though labeled A-26A is still the K model – Thailand didn’t want any “Bombers” based there. The USAF, to get around this changed the designation back to A-26, the B-26K COIN version became the A-26 again. That was fine – it was an “Attack” plane and not a bomber anymore. Makes no sense to a reasonable person, but it satisfied the politicians.

Third and fourth are the A-26 “Hard to Get,” full scale and a model of it.

Bill.

RE: Berkeley B 26
 

Bill, thanks for all your help. I think I'll wait to be done with the frame before I decide on the appearance. This wing's going to be a pain as I have no idea what the airfoil is and if I can just resize the ribs that I have.(might just do that anyway) I have some balsa laying around so I think I can get the fuse done here.


50%

RE: Berkeley B 26
 

Does anyone have one of these Berkeley B26's still? Any pics? Build might start tonight or tomorrow.

RE: Berkeley B 26
 

Well folks, The building has begun! I've started cutting out the formers on the fuse. I might have them all glued by tonight. There's 18 formers and most of them are in four parts, so this will be fun!(ok I'm using only an x-acto knife) The plans call for ply, but I'm using balsa. Maybe near the wing saddle I'll use some ply to reinforce since I'm going to screw the wing in. I'm thinking about using a wing tube and making the wing two parts. It will be much easier to do, but I don't know if I want to make the effort.(especially since I would have to incorperate the dihederal into my ribs) Any thoughts?


Chris

RE: Berkeley B 26
 

Chris:

Attached are the scans for the ribs on the Super Duellist 2/60, incorporating dihedral and a wing tube. Notice the changed location of the larger hole in ribs one through four.

If these are helpful to you, you can scale them to whatever size you want, designed for twelve ribs per panel.

Bill.

RE: Berkeley B 26
 

Thanks Bill!
I might use them.

Does anyone want to see a build thread? I don't know how many pics I can do, but if ya want, I'll try.


50%

RE: Berkeley B 26
 

50%,

It's always great to follow a build thread. I am still new to warbird builds, but i'm already attracted to twins. I currently have 3 Royal twin kits tucked away. The A-26 is a plane I used to watch operate out of the Ukiah Muinicipal Airport in Mendocino county, ca. They were used for fire fighting. Some time back, they had converted a few of them to turboprops. The converted 26s were soooo much faster. I don't know if they still operate there, but they might.

Scott

RE: Berkeley B 26
 

Does anyone know what the dihederal should be? I might just take a wild stab in the dark, but I'd rather not. From all the pics I've found of the B26, some have the glass nose and some don't. I know very little about the B26/A26, so can someone help me out here? The plans aren't very detailed, and yes, the plane is way overbuilt. Also, it shows two wing possitions. one for CL and the other for RC. I'm thinking about doing the CL, because the RC was probably to incorperate the extra weight, but I'm not 100% sure on this. I have half of the fuse framed up. I'll try to get pics sometime tonight, but you never know.


50%

RE: Berkeley B 26
 

"Does anyone know what the dihederal should be?"

On my Don Smith A-26, one wing measures 60 3/4 inches. The wing tip is 6 3/4 inches from level. I'll let you do the math. :D

RE: Berkeley B 26
 

Thanks Ichy!

RE: Berkley B 26
 

That's a lot of myth, a lot of hooey. The full scale did not even have that high a wing loading...it was only high relative to some of the OTHER planes of its day. Same with the models of it, they fly just fine, the Martin B-26 Marauder. Jerry Bates has plans for a large one, Mark Rittinger has plans for a small one.

RE: Berkley B 26
 

Both, belive it or not. A few were flown as RC back in the late fifties, doubt any LASTED that long! That was a real "advanced" project back then, quite exotic. As a CL flyer, no sweat.

50%, can I make a suggestion, before you go too far? Wing Mfg. makes a very nice A-26 kit, designed from the ground up for modern RC, with foam wing cores, all plastics, cowls...and a known good flyer. Before you get too far, look into it.
I'm a big Berkeley fan, myself, but unless I was doing a nostalgia project, and building it according to the orignal plans, for single channel or something, I would be looking for a better set of plans, with all ribs shown, without precarved balsa parts like the nacelles, and with available plastics...

RE: Berkeley B 26
 

To late, the fuse is almost framed. five more formers to go and then the carving and sheeting. The wing's going to be ok. I can resize the rib that I have for all the other ribs. I'm still debating a wing tube though.


50%

RE: Berkeley B 26
 

So what? You have an evening or two of work into it. Guaranteed, you will SAVE much more than that with the Wing kit.

Not saying the Berkeley cannot be done, just saying it's going to be much more work and risk than a proper RC kit...

RE: Berkeley B 26
 

I'm not building this plane for the purpose of flying it. I just want to build a plane that's hard to build. I fully intend to fly the plane though. I have most of the wood on hand, so there shouldn't be a problem there. I've changed the hatch layout accidentally. It used to go way back, but I don't see why that is needed. I've saved a lot of weight by using the balsa and eliminating many stringers, so I should be much lighter. Does anyone know what the normal weight of one of these planes is? I'm probably going to use four screws to secure the wing down and strengthen the saddle tremendously. Total weight gain from that should be about 6-10 ounces. Total weight lost so far is probably at least a pound. I've never run retracts before. Anyone have any suggestions? would GP's mechanical retracts work? I'm thinking about sheeting the wing with 1/16 instead of using the cap strips.I'm going to lighten the ribs up as well. The finish will probably be Monokote or paint. I want to use a chrome scheme, but I guess I need to find some good pics first.

50%

RE: Berkeley B 26
 

With a quick search of airliners.net, I turned up these pics. I saw a cool french scheme that I liked, but then I thought, French?? No way. so Here's the rest. I like the Fire Eaters a lot.

RE: Berkeley B 26
 

50%plane
Love a challenge huh?? You came to the right place. How about pictures of the build?
Twinman

RE: Berkeley B 26
 

Twinman, I normaly build from my own plans, so this is a little different.(harder) I don't like easy builds that much. I'll try to get pics up soon!


50%

RE: Berkeley B 26
 

Well, I just discovered that my building board warped on me and the fuse was screwed up. I corrected it for a total of 9 hours resulting in a mostly framed fuse. Hopefully I'll get pics up tonight.
I decided on doing this scheme:

http://image.rcuniverse.com/forum/up...13/Zl59753.jpg
If anyone has more pics of it I would greatly appreciate it!!



50%

RE: Berkeley B 26
 

You can do better than picks on this one. There is a video of it flying! At least I am pretty sure it was the Rude Invader.

http://www.wwof.com/cat/wb/

Look at disc 3. Was flown by Jeff Ethel who died some years ago while flying a P-38.

Darn, I have this on VHS. May have to reorder the DVD!

Also this link for a look at it's current condition.

http://www.warbirdregistry.org/a26re...6-4435752.html