Profile Depron foam XB-70 RC rocket glider, Frank Burke style

I had so much fun building and flying Franks 42" InteR/Ceptor that I decided to do a new model using Franks well proven technique.

Back in the late 1960s, I build and flew the very cool Competition Models XB-70 balsa profile free flight kit, powered by a Cox .020. Flew great! I think it will do great as a 6mm Depron RC RG.

This vintage plan is available on a model plane site:

https://www.outerzone.co.uk/plan_details.asp?ID=6639

I have already printed out a copy of the plan, enlarged about 10% so that it is just under 42" long. I have vinyl stars and bars and USAF decals on order for the slightly enlarged model.

The old design does not have the forward fuse represented in planform. I'll add that at the very least, or perhaps do the forward and upper fuse in a semi profile or full built up style so that the battery, RX and the ballast can be hidden inside.

I will ditch the reflexed airfoil in the delta wing in favor of a simple flat plate, I think. Might add a functional flap to the canard for glide trim, just for fun.

I am going to make a few small tweaks to make the model look more scale-ish.

The balsa free flight has a magnificent glide. I have zero doubts that the Depron RC RG version will glide just as well.

Stay tuned for more info as it progresses!

Tom, this is one I haven't done, but thought about. I'm sure it will fly fine with elevons only. If you are going to do the forward fuse, you might as well do a simple box, will be stiffer than a simple cruciform and can hide components. Are you going to do the bottom engine intake box or just a profile bottom spine?

From the top view its pretty similar to an aqm-37 jayhawk I've done..

Frank

I know it will do fine on elevons only. The canard flap is as much for fun as for function.

I do a fair amount of Depron RC electric stuff, so a built up forward fuse will not be a problem if I go that route.

Undecided on the lower fuse. Built up to scale would be nice looking, but more drag. Might keep it profile or fat profile there.

I have an XB-70 made of cardstock and 3mm Depron, 32" long with a BT55ish diameter, that does well on C6s. Uses standard rear ejection pod, and it has an elevator at the rear of the delta wing. Yes, it also has the wingbox (not a Valkyrie without, right?) as well as front canard (fixed).

Way older is the Readiboard version built back in 2004, around a BT60, using 24mm BP motors.

Have considered trying to make another version, even larger a bit, with just cardstock and 3mm Depron, to see how large one can be made and still hold up on D12/E9/E12's. Non-RC, of course.....

Made a fair amount of progress on the XB-70 over the last three days.
Here it is next to the InteR/Ceptor.




Decided to keep this one a simple profile. Will go full body on the next one, perhaps upsized for G25 power.

Still needs rail buttons, motor mount, hinges, linkage and radio gear and some more graphics and panel lines.

Ought to fly next weekend if we have our launch.

Looks great!

Thanks, Frank.

I have to confess that I have scaled up and tile printed several other plans this week.

North American XF-108 Rapier (a nice companion to the XB-70)
Convair Fish and Kingfish (designed, but never built, at the plant I work at in Fort Worth)
And one that would be really cool, a Boeing 2707-200, their SST design with variable geometry wings.
The Depron version would also have working VG wings, swept back for boost and swept forward for glide.

All these aircraft were designed to an advanced stage and mock ups were built, but none ever flew. Not sure that any of these four have ever been built as flying models of any type.

I don't know that I've seen a Boeing sst rc plane but it is a sexy plane, I live near the dc building and it had it painted on the side for many years...I've been wanting to do a swing wing version of my alcm but the tradeoff of weight versus boost improvement doesn't make sense, so I haven't pursued it.
I've done an ultra sabre but not a rapier, tsr-2 would be good as well.
Frank

I will occasionally sacrifice some performance for a fun working operational feature and the challenge of making something different work well.

The TSR-2 would be an great subject. A few years back I got to see both TSR-2 survivors over in the UK, at IWM Duxford and at RAF Cosford.

I have a few other subjects in mind, but the four I listed are towards to top of my list.

Last night I parked the XB-70 while waiting on a couple of parts and started cutting out the next two models.

After the XB-70 and Frank's X-15 that just arrived are complete, I will assemble the XF-108 Rapier and the Boeing 2707-200 SST. Will start a new thread for the dual build.

The Boeing SST will lag a bit due to some extra design and fab time for the wing sweep mechanism.

Ordered 18 E6 reloads today to stock up for the flying season.....

Cool Tom, I see you are going down my path, ordering E-6's by the gross....

Frank

Not buying by the gross quite yet..... More like a dozen and a half...

Hopefully will get to fly the XB-70 at the launch this weekend, assuming it happens. Might even fly the new X-15.

18 Packages or 18 motors? I usually order 20 packages of 3 at a time, take them all out, make sure they fit the casings, sometimes they need to be peeled a layer to fit correctly then put them all in a big freezer bag, with a bag of nozzles and a bag of o-rings....

18 motors..... 6 packages. I do have 4-5 packages in stock, though.

I will have to sell a few "excess to current needs" RC models to buy a gross of motors....

Well, the XB-70 just had an excellent maiden flight! Easy boost and excellent hang time.

Here is a post flight pic taken in between other flight at Hearne, Tx today. I added some windows to the cockpit since the last photos in the thread.

My normal photographer did not make it to the launch, so I will have to find someone's picture of the launch or draft a photographer for the second flight.

More to come.

Thats looking so sweet! Wish I was there, I'd certainly step up to the plate for foto ops, but alas I'm not. Hope someone does.


Richard

Not a lot of photographers around for the lower power stuff on Saturday.

I will do a photo session with my buddy Richard soon and document them all.

Here is a pic of me and the XB-70 that came from the Tripoli Houston Facebook page.

At long last, here are some action photos of the XB-70 flying at the SMALL model aircraft event, held June 2-5.

The first three photos are of the first flight on Friday and the rest of the photos are of flight number 2 on Saturday.

Handles very nicely, both during boost and in the glide. Good hang time! These two flights were the third and fourth flights of the XB-70.

And the last two photos of the second flight. Thanks as always to flying buddy Richard Ng for his excellent action photos