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Posted by burkefj | Aug 21, 2015 @ 01:02 PM | 1,790 Views
I'm still cutting kits for the SR-71, X-15 and InteR/Ceptor which can be delivered as rocket gliders or as pusher parkjets, or provided with an adapter to allow flying as electric AND rocket motor if desired. Since these are low production I'm hand cutting them and they take me over an hour to complete. Pieces are hand fitted and checked, many steps are pre-done, spars slotted/and/or installed, full flying tails installed or elevons hinged, horns installed, rocket mount completed, pieces taped for easy alignment after removal from the box.

Price is $44.95 per kit. Shipping is actual usps priority cost to you and I can fit more than one kit into a box.

Contact me via pm or for payment information.

Here is the link for more information:
Posted by burkefj | Aug 19, 2015 @ 03:34 PM | 1,672 Views
This is just for information only and I'm not suggesting you do or do not try this. This is what I have done and I'm just sharing the experience.

One of the big hurdles with using the Aerotech 24mm RC rocket motor reloads is the cost of the motor casing. Since this casing is machined from a single piece of aluminum(it has a solid end) and not a tube, it is double the cost of the standard 24/40 rms casing.

The E-6, D-7 and E-7 are endburning reloads meaning there is no flame front facing the front of the motor, till right at burnout. So, theoretically there doesn't need to be any delay parts/forward o-ring...NOTE: THIS CANNOT BE USED WITH THE e-12 RELOAD AS IT IS CORE BURNING AND THERE IS AN ACTIVE FLAME FRONT AT THE FORWARD END!!

I started thinking whether or not the rc reloads could work in the standard casing with forward closure, so I bought a motor tube and the forward closure and compared dimensions. The forward closure has a little flange that holds the forward o-ring in place in a standard non rc reload. That o-ring butts up agains a .032 fiber washer to seal. For that reason, it is not possible to use the rc reload as is in the casing, as the internal length is .032 longer than the rc casing internal length, AND the liner tube tends to slip over that little flange when pushed on by the nozzle, increasing this gap even further. This prevents proper sealing of the rear o-ring.(when you tighten the rear closure the nozzle flange pushes on the liner tube as...Continue Reading
Posted by burkefj | Aug 18, 2015 @ 08:55 PM | 1,229 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 | 1,610 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 | 1,729 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 | 2,348 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
Sticky: Kits Available
Posted by burkefj | Mar 14, 2015 @ 06:15 PM | 4,336 Views
I'm now cutting kits for the SR-71, X-15 and InteR/Ceptor which can be delivered as rocket gliders or as pusher parkjets, or provided with an adapter to allow flying as electric AND rocket motor if desired. I'm doing this as a service to folks who don't think they have the skill or access to the little bits and pieces. Since these are low production I'm hand cutting them and they take me over an hour to complete. Pieces are hand fitted and checked, many steps are pre-done, spars slotted/and/or installed, full flying tails installed or elevons hinged, horns installed, rocket mount completed, pieces taped for easy alignment after removal from the box.

Price is $44.95 per kit. Shipping is actual usps priority cost to you and I can fit more than one kit into a box.

Contact me via pm or for payment information.

Here is a video that shows the reloadable motor, all of the kits and control throws and flights for all of them.

Rocket Glider Kit Flight and Info Video (11 min 1 sec)

SR-71 kit :

X-15 kit:


Items Needed for completion:
1S 450mah lipo or 2s Lipo battery and BEC(voltage regulator for receiver/servos to convert to 5V
2 10 gram type servos, hs-55 hitec or similar
Transmitter with aileron/elevator mixing capability and ability to...Continue Reading
Posted by burkefj | Mar 03, 2015 @ 03:03 PM | 4,052 Views
My posted Plans are here:

Update 8/2015 Added Plans for the XF-85 Goblin, ALCM and F-107A UltraSabre

Here is a link to my youtube videos which cover many of my builds:

Here is a great wing CG calculator I've used for some of my odd wing shapes.

wing calculator:

For typical parts/equipment I use go here:
Posted by burkefj | Feb 25, 2015 @ 04:37 PM | 5,118 Views
I was asked for 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 re-did the plans, 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.

One note: If you are going to build as an electric, I recommend a small motor at the nose, such as a grayson microjet V-3. The tail mounted version I did required a very big battery pack, 2100, to get the CG correct. To build as electric, just don't cut out the rear rocket tube cutout, and mount a nose mounted ply plate and motor. I've marked three CG locations on the plans, the max rearward used for rocket boost, the nominal flight CG which would be used to start for electric, and the glide CG which is nose heavy....

Bare airframe weight is 4.5 ounces, but needed 3.5 ounces of lead for CG, plus a 1.7 ounce battery to compensate for the rocket motor....AUW rtf unpainted is 13.5 ounces. I got in 9 flights today. The wind kept changing on me, so it was tough to judge boost trim exactly, but glide was quite nice and docile. I needed to increase both aileron and elevon throws to...Continue Reading
Posted by burkefj | Feb 24, 2015 @ 11:32 AM | 4,751 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 | 4,991 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 DS6i 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.


For rocket flight:

2S battery: and BEC:
OR 1s battery:
servos: 2 of these http://www.graysonhobby....Continue Reading
Posted by burkefj | Dec 23, 2014 @ 09:11 PM | 5,050 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 | 5,139 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 | 4,725 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 | 5,478 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 | 5,585 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 31, 2014 @ 11:36 AM | 5,609 Views
Here is my X-15 rocket boosted RC glider,as a kit offering. 41" long and 20" wingspan, weight RTF is 9.5-12 oz for the aerotech reloadable 24mm E-6 rc reloads.

I'm doing these one at a time, and they take me an hour and a half to cut, they are not laser cut, but are hand cut and fitted.I'm doing a lot of the work for you,. All tabs and slots are cut and test fit. Carbon wing spar is pre-installed as are the full flying tail surfaces. The motor mount is pre made. Basic steps are shown here along with instructions, basically the steps are gluing pieces together and taping.


Airframe with carbon spar and full flying tail surfaces installed
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)

Needed to complete:
1S lipo 450mah or BEC(voltage regulator for receiver/servos) and 2s Lipo battery and nose weight, something around 1.5-1.7 ounces is fine, or use a lighter battery and add nose weight.
2 10 gram type servos, hs-55 hitec or similar
Transmitter with aileron/elevator mixing capability and ability to put elevator up-trim on a switch.
You will also need 3m-77 spray contact cement and foam safe CA+ and accelerator.
Depron compatible paint(model master/testors non laquer are ok)
silver sharpie for panel lines if desired.

Wing loading is quite light and glide is very docile. You boost...Continue Reading
Posted by burkefj | Oct 09, 2014 @ 06:45 PM | 5,623 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 | 5,834 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 | 5,706 Views