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Posted by burkefj | Aug 18, 2015 @ 08:55 PM | 5,675 Views
Here is a simple version of a Bell X-1E rocketplane. This plane started out as the second of the original X1 rocketplanes. Due to losses of other models, this one was rebuilt with a new cockpit with ejection seat, and a 4% extremely thin wing to go beyond mach 2. The wing is similar in thickness to the X-3 Stiletto.

I chose a cruciform since the wing is mid mounted. This does push the CP forward but normally the wing loading reduction is worth the tradeoff of extra nose weight. I used some strips of .03 styrene on the bottom of the fuse to prevent landing "road rash".

I installed a fully movable horizontal stabilizer since it is easy to set up on a single ply model like this. I used two 1/2" styrene .03 disks on either side of the vertical tail to support the elevator pivot, which has an aluminum tube glued through. The carbon rod goes throught that tube and is captured by small aluminum tubes on either side that glue to the carbon rod. The surfaces are then glued and taped to the rod. I used a micro servo horn from dubro glued to the carbon rod to connect to the pushrod.

I chose to use the flap area on the real wing for the ailerons and left the small outboard ailerons as decorative only.

I'm using a single 450mah 1s lipo direct to the spektrum 6115e and it seems to run the 3 hs-55 servos fine, at least for 4 flights.

Since the CG is required to be about 5/8" behind where the wing le hits the fuse, it required 4 oz of nose weight. Total auw rtf with rocket motor is just over 12 oz. It's about 37" long and 26" ws.

Flights were nominal, needed just a bit of roll trim post-boost along with some up trim. Here is the video, in reverse order of the actual flights.

Bell X-1E RC rocketplane (2 min 35 sec)

Posted by burkefj | Aug 11, 2015 @ 04:44 PM | 5,838 Views
I wanted to build another big foam rocket using depron, and chose the Pershing 1A since it has tiny fins and typically needs lots of nose weight. I had done a 5.5" version previously that flew well but wanted something a bit bigger. The plan was to try to hit 4.5 pounds fully loaded and fly on H-180 29mm motors. I used 6mm depron centering rings and stringers, 2mm skin, and a core cardboard 29mm stuffer tube that acts as a spine. the upper parachute bay is 4" by 12" long and is pml phenolic to contain the ejection charge. Ejection is by altimeter which is in a magnetic hatch area in the rocket body. The ejection charge wires go up through the stuffer tube into the parachute bay and through a little cap that fits into the top of the stuffer tube. The parachute bay can be so small because the weight is light enough that I only need a 48" lightweight chute. Fins have some select placements of carbon inbetween laminations. The cone was from a craft store and then sheeted with 2mm depron, and a carbon rod goes up through the middle to take the landing loads. The shoulder is a pml coupler and the forward recovery attachment is to a 3/32" ply plate that is glued to the carbon rod/foam cone. Since the shoulder is hollow it doesn't steal any of the parachute bay area. I have not had to add any nose weight at all in this model which is almost unheard of in a Pershing 1A. Diameter is 8" and length is around 80".

In order to do...Continue Reading
Posted by burkefj | Aug 05, 2015 @ 04:20 PM | 5,535 Views
Recently I found my plans for the XF-85 goblin I had done back in 2008, and found the video. I decided I'd build a new one as the old one was lost in a move. I started with the plans as they are posted. I decided to put in my normal 24mm rocket mount just so that I could use my same plug in motor pod with a grayson microjet.

Here is the flight video of the new version, below I give more detail on what I did:
McDonnell XF-85 Goblin RC parkjet (5 min 34 sec)

I had designed this with a fully movable elevator to give sufficient pitch control, and kept them horizontal as people have had pitch control issues when trying to use the angled tail surfaces.

In order to clear the rocket motor mount with the elevators. I extended some permanently mounted stubs and mounted the movable surfaces outboard. If you do a normally mounted motor in the tail you don't need to do that. I went with dual servo ailerons since they are simple.

I considered doing a top view as well, but that would have moved my CG even further forward.

The changes I made were to add a doubler just on the bottom half of the fuse below the wing, this gives something more substantial to land on and allowed me to hide a little carbon rod stiffener for the back half(it was a bit flexy) and allowed me to hide my nose weight. I also went with a round 1/8" carbon rod A frame wing spar setup since this version was going to weigh more than my original. AUW for this version was 12 oz. The ventral stub...Continue Reading
Posted by burkefj | Jul 30, 2015 @ 06:44 PM | 5,941 Views
I decided to do a slight modification to my rocket boosted ALCM today to allow it to be used as a pusher as well. Originally the ends were square straight and it did not allow any air to get to a propeller(did not matter for the rocket glider). I trimmed the ends and tucked them in which is actually more like the real thing.

Boeing AGM-86A ALCM RC Parkjet (5 min 39 sec)

Here's the original build thread with construction photos...

I was able to drop an esc in from the front hatches, and run the wires to the back and hook it up to my motor pod and the 3s 800mah pack didn't require any additional nose weight. Nice thing is for rocket boost, I can just pull the motor wires up, roll them and velcro that and the esc in the front of the model with a 120 2s pack and I don't have to add any nose weight for rocket boost either.

I had three flights this morning, starting with a CG about 3/8" ahead of my rocket boost CG, then moving the CG eventually back slightly behind the original rocket glider boost setting. Interesting thing, it took quite a bit of up trim for level flight, but increased speed didn't change pitch, in fact it was very straight flying, even with just the tail surface control. As I moved the CG back I thought the up trim would come off, but it wasn't the case. I think the angled flat nose is pushing down or something. In any case, it flies very nicely, good roll rate, nice pitch, very nice slow flight with no bad tendencies, looks really good,...Continue Reading
Posted by burkefj | Feb 25, 2015 @ 04:37 PM | 8,649 Views
I was asked about my ME-163 komet plans that I had done a while ago. The first version I did used a single ply wing with a couple of spars, however due to the rear mounted motor and the balast needed to get the right CG, the wing had too much flex and I wasn't really happy with it. So I doubled the leading edge of the wing, changed the spar type and location, added a cross spar, doubled the lower fuse to better withstand landings and made it a rocket glider. Step by step photos are included. I was almost able to keep it on one sheet, just the tail extension didn't fit.

Update 6/2015
I've since also flown it with my grayson microjet V-3 motor and an 800mah 3s pack and it flies very well. I had to add a touch of extra nose weight but it carries it really well, it will fly at almost full up elevator and not stall out, inverted takes almost no forward stick, really a nice performing pusher.

39" span.
...Continue Reading
Posted by burkefj | Feb 24, 2015 @ 11:32 AM | 7,665 Views
Here is the NARCON 2015 presentation I did on rocket glider and large rockets using depron. Hope you find it interesting. If you view it in slide show mode the bullets will appear one by one. It's in a zipped file, you'll need to unzip it. When you click on the youtube links you will need to minimize the power point and expand your browser youtube window.

Posted by burkefj | Feb 18, 2015 @ 01:45 PM | 7,449 Views
Hi, here is a quick rundown on common parts I use, the foam, servos, etc are all needed, the micro horns or carbon rod may or may not be needed depending on the model. You can always use cheaper parts, this is what I use and I know they work, ymmv.

Foam safe CA+ with accelerator for most glue joints.

3M-77 spray adhesive for laminating if needed.

Servos, I have used HS-55 servos for allmost all my gliders, they are light and I've had little failure using them. The hs-65 carbonite gear and HS-82 MG and HS-81's are all good too, heavier but more torque, not really needed for most of my rocket gliders.

Transmitter: I use a DX7, but this Dx6i has most of the same features, 10 model memory, mixing, flap switch for glide trim...pretty inexpensive.
Receivers, whatever you are comfortable with. I fly spektrum and use the AR400 now as it is full range.
Most receivers can run with 3.5V or better input so a larger capacity 1S battery(450mah) should work fine. Servos can run a tad slower at lower than 4.8V so you should check and make sure you are happy with your setup if you go with 1S. The 1S batttery should have a plug that is compatible with your RX.

You can go to Grayson hobbies and find most of these items or check your local hobby shop.

Transmitter: Spektrum DX-7 or DX-6i

For rocket flight:

1s battery: need to put a compatible connector for your rx)
receiver: Spektrum AR-400
servos: 2 Hitec HS55

For electric...Continue Reading
Posted by burkefj | Dec 23, 2014 @ 09:11 PM | 7,415 Views
Here is another large rocket I designed/built using depron structure. I chose the Jupiter C that launched our first satellite. I'm using a 29mm stuffer tube with a 14" long by 3" diameter parachute bay as the spine. Only ply used is a thrust plate at the bottom, and one at the upper section to attach the recover device to. A couple of internal ones to center the 3" tube.

I found a funnel at a craft store and trimmed it to adapte the satellite to the second stage tub.

The transition at the top is a little oversized due to the 3" tube going down into it.

I built up the second stage can using depron stringers and sheet. The satellite is made from bt-20 tubing which is slightly oversized.

Target weight is 53 oz rtf with a G motor, right now it might be an ounce or two over due to the density of the 2mm sheeting I got being higher than the online spec.

The altimeter has an access hatch held closed with magnets.

Right now sheeting is done, I just need to build the fins, and add some details.

Diameter is 7" and height is 82.5" long. It should handle most 29mm H motors as well as any g motor....Continue Reading
Posted by burkefj | Dec 14, 2014 @ 12:55 PM | 7,422 Views
When I was at KSC for the Orion capsule launch, I got some photos at the Canaveral air force base missile museum, thought I'd share them.

Highlights are the saturn V, orion capsule mockup, Atlantis, Navaho, Minuteman 1 re-entry vehicle, Pershing 1A nose cone, atlas booster motor....Continue Reading
Posted by burkefj | Nov 24, 2014 @ 12:03 PM | 7,006 Views
I wanted to build another large scale rocket using foamy build techniques....Idea is to take a rocket that typically needs lot of nose weight and build it light enough to fly on smaller motors. Using sims using normal 1/4" ply, fiberglass for the nose and LOC 7.5" body tube the balasted weight ready to fly is 20 pounds for this model with a proper CG location using J-570 motor.. My goal was to try to get it close to 3.3 pounds, final result ws 4 pounds 2 oz with balast less motor, motor required will be an H-128 minimum... I'll run altimiter deployment with motor ejection as backup. The hellfire requires about 1.8x the weight in the nose for every ounce of tail weight(motor) so you need to keep the rear end light. This is full scale, the Hellfire is 7" diameter and 64" long. The advantage of building this way is you can create your centering rings and sheeted tube to whatever size you want.

Using rocksim CP calculation which is less pessimistic than barrowman estimations shows the CP to be 31" from the nose and with one caliber of stability margin, CG should be at 24" from the nose, or just in front of hte middle yellow band.

I got good deal on 18" body tubsfrom sunward for $6 (pack of 5), couplers for $3, some leftover 6" 3.9" couplers for $4 each, and a 29mm motor mount kit(provided a tube that fit into the bt-55 and three 3.9 to 29mm centering rings)and used three sheets of 6mm depron and 2 sheets of 2mm sheeting....Continue Reading
Posted by burkefj | Nov 18, 2014 @ 11:17 AM | 7,584 Views
I've been wanting to try this for a while, the work I did on my Dyna-soar/Titan II got me motiviated. I do a lot of depron RC airplane construction, my thought was to do a model that typically needs lots of nose weight or is very heavy, and see if using stringers/centering rings and 1mm depron skin I could make a large light model to fly on E-15's......

The only wood in this model are two centering rings in the upper portion that are lite ply, and the balsa coupler I used for my BT-70 upper tube since it was handy at the hobby shop, the rest is depron sheet, cardboard motor tubes and some .04 styrene sheet.

For drawing centering rings I've been simply using a strip of cardboard, put a thumbtack in one end, and measure to the needed radius, poke a hole and insert my fine sharpe and draw it directly on whatever I need to cut, no need for a compass. This can be used for drawing cones or transition shrouds as well where you need a very long radius.

I cut a 7" by 2" triangle out of 6mm depron, grooved and glued in a 1/8" carbon rod which will take the brunt of the nose cone landing force....I then added perpendicular triangles, and took turns gluing in triangle filler pieces and carving those to match the original triangle pieces a quarter at a time...eventually I had nose cone shape. I left one quadrant unfinished so I could add weight if needed, then finish it. I added a few gradually increasing centering rings to get the needed outer diameter.

I cut off a...Continue Reading
Posted by burkefj | Nov 05, 2014 @ 11:40 AM | 7,630 Views
I've been wanting to try to adapt my X-20 to a titan booster. Since the X-20 is large and lightly constructed, the booster would have to be light enough and large enough that I could use lower powered rocket motors to keep the speed down so that it wouldn't rip the X-20 apart on boost. I wanted to try a center 29mm motor tube and use depron centering rings, longerons and a 2mm skin. I wanted the all up weight without motor to be 60 oz or so less the glider. For reference 60" of standard 7.5" loc cardboard tube with a coupler weighs 60 ounces.
Lots of photos so read the whole thread to see final construction photos of the booster....
Length will be 108.5" and 8.25" for the booster to be standoff scale with the drawing I have. Ideal motor will be a 29mm H-97 or H115 that have a pretty flat mild thrust curve..

Here we go.

Here is the rocket simulation, and here is my original X-20 that boosts off a rail on E-6 24mm reloads, here is a quick video of it flying.

X-20 Dyna-Soar rocket boosted RC glider Launch Video (0 min 33 sec)

If this all works, the glider will be ejected via a piston that will also pull out the booster chute, and then I'll glide the dynasoar back. If that works ok, I may try doing an air start of the dyna-soar once released.
Posted by burkefj | Oct 09, 2014 @ 06:45 PM | 6,890 Views
Had a great launch down in Amity Oregon, Gary Goncher got some great shots of 6' bomarc and 6' boeing ALCM in flight.
These were both flown with 29mm hardware and the new G-25 moonburner Aerotech reload. It's a great motor for these depron planes as it doesn't push them too hard, but has a good spike to get them off the pad, they both weigh 32-35 oz rtf. It's also nice because it uses the normal 29mm highpower motor hardware and not the more expensive and custom sized 32mm RC hardware. It's not as hard a thrust profile as a G-38 or G-40, but it's almost a full 120ns motor.

Posted by burkefj | Aug 10, 2014 @ 08:50 PM | 6,971 Views
I had built a 30" long natter rocket glider back a few years ago, designed for estes E-9's or E-6 aerotech motors. The AUW though due to the forward CG was 13 oz and the wing area was a bit small for a good glide.

The original full flying tail was a bit big on this upscale, so I trimmed the inboard ends and mounted them permanently to the tail which helps stiffen it, and then just did full flying outer portions. I mounted the servos on the underside of the fuse and just angled the pushrods up to the tail surfaces and they lined up nicely. I added two parallel carbon struts from the tail to the fuse to prevent slight twisting under hard roll inputs.

I decided to do 136% upsize to make the length 41" and just fit onto a depron sheet at an angle. This gave me almost 2x the wing area and the Due to the longer length and same tail weight, the nose weight was reduced somewhat and AUW came in at 15 oz rtf.

I used some olive model master spray for the body with some flat gray camo using a cardboard stencil/template I made. I used some silver sharpie to do panel lines and a bit of trim monokote for the windows.

I used some thin styrene sheet laminated on the outside of the depron to support the pivot rod for the tail and to help prevent twisting. Had two test flights today, boost was nice and straight and glide was very slow and docile, a lot nicer than the original smaller version. I now have 11 flights , just put in a bit of downtrim for boost setting and reduced uptrim for glide to make it more hands off.

Here's the video..:

Scratch built Bachem Natter RC Rocketed boosted glider (1 min 22 sec)

Posted by burkefj | Feb 03, 2014 @ 01:55 PM | 6,609 Views
Links to current build threads in my blog:

ME-163 Rocket glider:

X-20 dyna-soar with titan booster:

Bachem Natter:

F-8 Crusader:

F-4 Phantom:

Mig 21:

F-105 Thunderchief:

F-102 Delta Dagger:

F-106 Delta Dart:

B-58 Hustler:

Spaceship one:

X-15 Delta Configuration:


Upscale AGM-86 ALCM:

Upscale Tomahawk:

Space Battleship Yamato:

Upscale Bomarc Missile:

Large InteR/Ceptor:

X-3 Stilleto:

Large X-15: http://www....Continue Reading
Posted by burkefj | Jan 27, 2014 @ 12:53 PM | 8,391 Views
I've been going through my old designs/plans and slowly re-doing them for public consumption, originally I did an F-8U-III super crusader which was basically a similar design except for the nose and intake. I decided to make it a straight crusader this time. You could take these patterns and make a pointy nose and curved intake snout and re-do it as a super crusader. There are slight wing differences but probably not enough to notice. On the super crusader you'd have to figure out a way to model the ventral fins which are either horizontal or vertical and quite large, on mine I just created some ventral strakes that sort of modeled them from the side view in takeoff position.

I used a center piece with tail and then two doublers on each side to give me enough thickness to give a nice rounded nose and intake.
It would be easy to add some formers or pink foam and add thickness to make it fully 3-d.

Originally I mounted the wing on the top of the fuse with some tabs and glued a fairing cover over the top. On this version, since the real plane has some airfoil thickness, I decided to pick the most forward point of the wing leading edge and use that for the slot location. I think it looks ok like this and allows some foam above the wing to hold it in place and model the fairing that is on top of the wing. In order to lock the wing in place, I'll drive some 2" pieces of 1/8" carbon rod down through the top of the fuse through the wing and into the body and...Continue Reading
Posted by burkefj | Jan 17, 2014 @ 01:13 PM | 8,732 Views
I decided to do another Phantom build, make a few changes to the original and plans. I originally did these because there weren't great simple plans for a phantom at the time. I'm not a big fan of mid mounted engines or box fuses, I'd rather have a slim profile, gives less drag in the air and is quieter. It does require you to mount equipment on the bottom of the wing has the battery mounted on the front side of the nose, but I'm ok with that. Due to the thin profile the wing hits the fuse further forward than on a normal fuse. If desired, you could alter the top view of the wing to include the intake profile and nozzle profile on the rear of the wing so that the top view was more representative, I considered this and decided to leave it clean. If you do this you may need to do some glide tests to confirm CG did not shift as the intake profile will add forward wing area. The wing is not mounted on the bottom, but is in a slot, I did this to give a bit of area under the wing to mount the electronics and not get destroyed on landing.

Flight video at:
F-4 Phantom parkjet flight 1 (4 min 18 sec)

Here is the Rocket boosted flights...

F-4 phantom scratch built parkjet/rocket boosted glider (2 min 0 sec)
...Continue Reading
Posted by burkefj | Jan 13, 2014 @ 12:41 AM | 7,935 Views
While recovering from my foot surgery, I was watching all sorts of youtube videos on F-105's etc.....Then I realized I don't have any enemies for my thud. I decided to go back to my original Mig 21 profile and change it to a cruciform style instead of a true profile fuse...This saved a bit of weight, but meant the CG would have to move forward a bit. It did give more surface area though so the wing loading would decrease. I went back to my mig thread and saw some pictures a guy had done with panel lines so I went that route. Looks like rtf it will be about 11.5 oz. Did my normal rocket motor mount so I can do rocket glider or with my pusher pod installed.

I went with Czech markings as I have some bohemian in my blood....

Maiden went well, was a little too nose heavy, so removed some weight and it flies really nicely, was a bit windy today.

Mig 21 profile pusher RC parkjet (3 min 42 sec)

Posted by burkefj | Jan 06, 2014 @ 06:36 PM | 8,374 Views
I discovered that the evergreen aviation museum has a thunderchief now on display....It was a nice sunny day so I took some photos....didn't take me long to decide to upscale my original 3mm micro version to 6mm and 39" long...Kinkos did the scaling for me from my original plans. I decided to use a doubled central fuse with two side doublers, and 3mm covers over the rocket mount that also doubles for mounting my grayson microjet motor. Plane is already framed up awaiting an esc and maiden to confirm the CG. I stuck with a full flying tail only. This is a single seat D version. Not sure on the colors yet, I'll probably go with the light bottom and camo top like these photos..... Here are some pictures from Evergreen.....The original small version, and my newer version.

Update 1/7 Finished the painting, now just need to do some panel lines, a few letter markings and wait for my ESC.

Update 1/8 Finished the markings and panel lines, esc is in today but rain for the next week Looks like right around 14 oz rtf.

Update 1/13 Maiden went well, CG was right on, was very windy today but handled it well.

Video will be at:
F-105 Thunderchief RC parkjet (2 min 17 sec)

...Continue Reading
Posted by burkefj | Jan 06, 2014 @ 04:58 PM | 8,074 Views
F-106 Delta Dart Kit weight RTF is 10-12 oz for the aerotech reloadable 24mm E-6, D-7, e-7 rc reloads and Estes D-11P, D12-0* and E12-0*. These kits are hand cut and fitted.I'm doing a lot of the work for you, Fuselage sides are laminated with a carbon nose reinforcing, wing spars are pre-slotted, Elevons are pre-hinged. The motor mount is pre made. The joints are pre-taped so you unfold them, apply CA+ to the joint and they are ready to be assembled...As an option the kit can include a pre-built adapter that clicks into the 24mm rocket mount and has a ply plate that allows you to mount a pusher electric motor so that you can convert from rocket to electric in a few seconds. Basic steps and instructions for download are shown below, basically the steps are gluing pieces together and taping.

For ordering or more information go to


Airframe pieces with carbon spars, elevons (pre-installed)
Control Horns
Nose weight
Motor mount
Rail buttons and screws or launch lug(your choice)
styrene strip for reinforcing
velcro for mounting rx/bec/battery
blenderm tape(for taping wires and reinforcing joints)

*(Estes motors require a small amount of epoxy to be placed in the front of the motor so that the motor is not ejected and does not damage the foam) . This is not a manufacturer approved change and is not allowed by NAR rules but is an option if you are launching in your own field....Continue Reading