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Posted by burkefj | Jun 06, 2016 @ 12:10 PM | 6,551 Views
Sunday it was 100 degrees out so stayed indoors for the most part. I've always wanted to do a concorde but never have...so I gave it a shot. I started with the tubes/coupler/cone from the Estes Cosmic Interceptor. For the fuse, I angled the rear of one of the tubes with a cut to simulate the tapered concorde rear. I inset the motor tube at the bottom of the cutout, (Motor tube is right above the wing and even with the TE). I was limited on how much of an angled tail I could leave sticking out the back since my tubing was a set length and I knew I had to have sufficient forward length to avoid adding nose weight. I used two spare 1" wide body tube pieces I had to lengthen the center section 2" and left 3" to the rear of the wing as a compromise. I Joined the two body tube pieces and the two main body tubes using a coupler.

I used the basic wing planform from my Arc-Light kit, I adjusted the front of the wing and wingtip shape and mounted the wing on the bottom of the tube. I knew the added wingtip area would move the CG back about 3/8" which would help cg. I slotted and installed a concord-ish vertical tail which was large enough to give me lateral stability. I added some support gussets in the wing/tube joint to give extra gluing area. The receiver is mounted at the front of the body tube using velcro, and the single cell lipo is mounted just inside the shoulder of the nose cone. I removed the base of the nose cone so I could mount the...Continue Reading
Posted by burkefj | May 20, 2016 @ 04:18 PM | 6,487 Views
I have designed three new rocket gliders that I'm now kitting as well through www.dynasoarrocketry.com.

The first is the Hypersonic, it's based on an X-15-3 Delta wing configuration proposed to push the airframe past mach 7 just before the project was cancelled. Uses 2" tubing and a plastic nose cone, a straight delta wing from depron. 38" long, 20" wingspan and 12.5 oz rtf.

Second is the Arc-Light a little more rakish, based on a 2" tube, this kit uses the nose cone and tubes from the cosmic interceptor rocket kit from estes and ads a lightly cranked delta wing and high t tail and drooped wingtips. Wingspan is 20" and length 38" and weight rtf is 12 oz. Again, a really nice flyer, the video shows it flying in about 9 mph winds and it handles boost and glide really well, hope you like them.

Third is the Pegasus, very similar to the Arc-Light but with a triple swept tail design.

Dynasoar Rocketry Arc-Light RC Rocket Glider Flights (5 min 23 sec)

Dynasoar Rocketry Hypersonic RC Rocket glider kit flights (3 min 54 sec)
...Continue Reading
Posted by burkefj | Apr 05, 2016 @ 11:18 PM | 6,511 Views
Here is another one I did a long time ago and wanted to update the shape and plans. I always wanted a sig kobra which had a sort of similar shape/color scheme and I've always liked the F-100 in thunderbird scheme, I decided not to paint it silver and just leave it white to save a bit of weight. I did the vinyl freehand and it's not perfect, but came out looking ok. Added the panel lines and some titanium/silver for the exhaust/afterburner area since this typically shows through on the F-100 even when painted...

Here are some build photos as I went along. Maiden this morning was really nice, just a few clicks of up and a few of left aileron and it was good to go. I'm at about 26% MAC for CG and it is very docile. Very slow high alpha and good loops and rolls. 4:40 flight time with an 800 3s pack, and grayson microjet V-3 and tbird 18 esc and apc 6x4E prop. 16 ounces auw rtf.

Plans as usual are at: http://www.dynasoarrocketry.com/plans.html click on the picture of the plane and there is a little link icon in the bottom right corner, click that and it should download the pdf.

Note that the wing is a c model with a straight trailing edge, if you want a d model you can simply cut the Te perpendicular from the inboard aileron tip to the fuse and enlarge the fuse slot to match. You may be able to move the cg back slightly.

...Continue Reading
Posted by burkefj | Feb 16, 2016 @ 06:27 PM | 5,999 Views
I've been flying my Mach 2 rocket glider kit I make quite a bit with pusher motor instead of rocket glider, I've done several versions, german, US and Russian...I've been having a blast, I'm surprised how well it flies, really pretty precise and no bad habits, just a great flying plane....I like the look, sort of Huckebein, sort of mig 15, a little F-86ish....One of my customers did a nice version with a pseudo Eastern Front Winter scheme....

Mach2 RC pusher parkjet flights (4 min 40 sec)

Posted by burkefj | Feb 16, 2016 @ 06:25 PM | 5,729 Views
I did some modifications to my IntR/Ceptor rocket glider kit, getting rid of the horizontal tail surfaces and going with just elevon control on the wing. As such, i was going to retire this original version. However I wound up sticking a pusher motor on it and giving it new life, it is a very nice flyer and looks really good in the air. It's 12 oz rtf and about 42" long and 20" wingspan.

IntR/Ceptor RC pusher parkjet flight (5 min 17 sec)

Posted by burkefj | Feb 16, 2016 @ 05:42 PM | 5,714 Views
Another of my older designs that I had flown as a rocket glider quite a bit, since I've now built a full tube based bomarc missile, I wasn't planning on flying this again, but I decided to pull it off the ceiling, and add an esc and fly it as a pusher to give it some more life. Handled the 10-12 mph winds pretty well, even though the wing is small and it weighs 14 ounces, it still was able to hover, or at least stay in one spot pretty well.

About 48" long, 22" wingspan...

RC Bomarc Missile parkjet Flights (17 min 8 sec)

Posted by burkefj | Feb 02, 2016 @ 11:48 PM | 6,119 Views
Got my old Buran down from the ceiling, did a modification to make the nose look better and pulled out my old electronics and installed a bec-less setup with a single cell lipo directly to the receiver. Re-balanced and got down to 14 oz, here are three flights today, still fat and draggy and but still a nice flyer, for a shuttle. I decided not to add any tail detail just to save tail weight and make it a bit simpler to construct.

RC Space Shuttle Buran Rocket Glider (2 min 14 sec)

Posted by burkefj | Jan 16, 2016 @ 03:40 PM | 6,557 Views
I was on the way home yesterday and was thinking about changing my IntR/Ceptor profile model into an elevon only model, instead of one with full flying tail surfaces. This would require moving the wing back and making it larger. I remembered that the hobby shop had an Interceptor E kit that had been sitting on the shelf for a long time. I did some quick checking and thought I could do a modification of this to keep the tube and nose cone and see if I could get it to fly ok. I did some quick wing planform checks and came out with something I thought would work.

I dumped the wingtip pods since they are heavy and will re-make those from foam. I enlarged the existing wing/tail slots to fit my depron surfaces and installed the wing. I made the forward tube section removable along with the strakes so that I can access the mid mounted rail button. It turned out for CG I did need to use the plastic tail piece. 7-8 ounces/sq foot, slightly more than my full profile version. The need for the tail cone for CG means the motor is inset about 3/4"

First flight was really good, slightly nose heavy, and a bit touchy on roll. I adjusted the cg rearward by adding 1/4 ounce to the tail and toning down the aileron. I later replaced the 1/4 ounce of tail weight with the plastic vertical stab antennae which weighed the same overall. I added some panel lines, accented the nose cone panels with a sharpie pen and added some trim vinyl. All up 12.5 ounces rtf now.

Here are videos of all three versions plus my kit profile version.

Four Variations of Interceptor RC Rocket gliders (5 min 15 sec)

Posted by burkefj | Jan 10, 2016 @ 07:47 AM | 5,266 Views
Here are two rocket gliders using lightweight tubing. The first is a retro shuttle sort of design, trying to replicate the booster portion of the old Centuri Space Shuttle which had a piggyback glider and booster that were both gliders. I always liked the booster design, and since I didn't have a piggyback glider added a third central fin in a similar shape to the piggyback glider just for extra lateral stability. I also did a top mounted wing so I didn't have to cut the tubing. Canopies are folded photo paper glued to the cones. I did it with both a short nose and long nose, decided the long nose looked better but makes it look more like an XB-70 than the original design....This is 11 oz rtf for 24mm rocket motors

The second is a Bomarc Missile. The bomarc has a pretty small wing for the weight so the glide is not long. My profile version glides much better but this tube based one is much better looking. 16 oz rtf with 24mm rocket motors. So far the ramjets are holding up well to landings.

Here are the latest flights, the Shuttle flying on an E-6 and the Bomarc flying on an Estes and aerotech E-12 motors
Rocket boosted RC Airforce Shuttle Concept glider (1 min 3 sec)

RC Bomarc Missile flying on E-12 rocket motor (0 min 30 sec)
...Continue Reading
Posted by burkefj | Dec 19, 2015 @ 05:34 PM | 6,093 Views
Here are the flights from today.

Upscale Centuri Mach 10 RC Rocket Glider Flights (3 min 44 sec)

The prototype in US markings and the first kit cut from templates done in soviet style markings.
Posted by burkefj | Dec 19, 2015 @ 01:09 AM | 5,736 Views
I had a break in the terrible weather and got two maiden flights in of the X-24A and X-20 style profile lifting bodies I did based on the HL-10 wing...really easy to fly.

Dynasoar Rocketry Lifting body style RC Rocket Gliders (2 min 12 sec)

Posted by burkefj | Dec 16, 2015 @ 04:20 PM | 6,009 Views
Went back to this design last night. it's based on the old Centuri mach 10 which used an angled tail and an offset motor and ejected a nose weight for glide.
My previous version used a center mounted wing and no angled horizontal stab and did not eject anything. For this version, I rolled a 2mm depron skin over a 4" body tube double thick using 3m-77 contact cement. I then mounted it to a wing, the vertical tail slots through the tube put a 1" keel on the bottom to stiffen the tube and mount my rail buttons on. it will also protect the servo arms from landing damage. I made a cockpit from photo paper . AUW empty is 7 oz, with radio and rocket motor is 11 oz rtf,.

The tube is completely flow through
24" long, 32" wingspan, 4.5" tube, wing loading a bit over 5 oz/sq foot.

...Continue Reading
Posted by burkefj | Dec 10, 2015 @ 09:50 AM | 5,444 Views
I've moved my plans page to my own web site now so I only have one place to manage things.

You can go to www.dynasoarrocketry.com, There is a plans link at the top. If you look under the Instructions link at the top there is more information on construction and links to some of the recommended components for rocket flight and finishing. If you go to the "converting to electric flight" link at the top it covers components if you are building as a pusher parkjet.

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: http://wingcgcalc.bruder.com.br/en_US/?
Posted by burkefj | Nov 29, 2015 @ 05:14 PM | 6,558 Views
This is loosely based on the HL-10 but with a wider span to reduce roll oscillation that was prevalent in my previous X-24A that I made. I also modified the shape somewhat to reduce the lower half of the model and moved the motor/vertical stab forward to make it easier to get CG correct. It's a very docile and well behaved model. Boosts nearly hands off, really minor steering inputs required, pitch control very good right up to nearly standstill. I've put the plans on my plans page. There are three spars, one accross the span and two in line with the leading edge to add some stiffness. The keel is double wide which allows me to mount the rail buttons directly through some styrene skid material and add two wing skids ahead and behind to protect the buttons on landing. the wing tips are supported by a 6mm gusset and angled outward slightly and have a very slight toe in for some shuttlecock stabilization drag. Decals I worked out through stickershock23.com and they put a nice touch. The panel lines are all with a sharpie fine line marker and straight edge.

The HL-10 was not an air force model but there was a prank where markings were applied to the HL-10, and I think it looked less plain this way.

Wingspan is 24"(20" would be scale), length 31", 12.5 ounces rtf with a rocket motor. I'm running a single cell 500mah eflite battery straigh to the spektrum AR-400 receiver and 2 hs-55 servos. Really simple light setup.

Here's some flight video

HL-10 lifting body RC profile rocket glider (4 min 15 sec)

It's available as a kit at www.dynasoarrocketry.com

Posted by burkefj | Nov 03, 2015 @ 12:03 AM | 6,667 Views
This is a Titan II Missile built using a 29mm loc stuffer tube with a 14x4" pml phenolic parachute bay. the idea was to do a lighweight version at the same scale as my heavy duty 20# version. 7.6" diameter, 82" long using 1/8" lexan fins.

In order to make the lexan fin mount solid(since you can't rely on the foam to be strong enough for landing loads) I used two ply centering rings at the rear with hardwood pieces that made slots in the front and rear of the fins. Those act as guide slots in effect. For the nose I found a 2.5" hardwood decorative ball at a craft store, and turned it in my drill press to make a shoulder. This will also add a bit of nose weight for the model.

For the nozzles I found some stainless steel measuring jiggers that had measuring lines that look pretty good. I used some standoffs and made some piping out of flexy straws painted titanium color. The central motor will fit inbetween the nozzles.

I used the rear centering rings as guides for cutting out all of the depron centering rings. I then cut the longerons and assembled the straight structure over the stuffer tube. I then skinned it using a 2mm depron skin. I then built the tapered section that would be part of the nose and skinned that. Once complete I slid the nose section onto the stuffer tube centering rings. At that point I applied the silver trim monokote to the front and rear and added the vinyl markings that Mark at Stickershock made for me. The...Continue Reading
Posted by burkefj | Oct 12, 2015 @ 12:02 PM | 7,462 Views
Here is the latest in my construction of large relatively lightweight rockets using depron as the primary structure. In this case the Atlas Missile, our first ICBM.

10" diameter, 82 inches tall, 6.3# AUW. I used my normal method of using a 29mm core tube with a 4" parachute bay at the top, the warhead section fits into the 4" parachute bay via a coupler and will be the part that ejects. Altimeter on the side near the transition with wiring that routes up the 29mm tube into the parachute bay. I've used some bt-70 for the warhead.

Again, the point of this is to make a large rocket that won't fly super high and can be flown in small areas. The structure and recovery components are sized for the planned weight, thrust and recovery/landing loads. I used a spreadsheet to keep track of each component weight and my rocksim simulation to get estimated CG to avoid having to add any additional nose weight. In the end I had to add only 3 oz to the nose, primarily becasue of my choice to use clear lexan fins which are heavier than foam/carbon.

The model is covered with monokote trim chrome and silver, only paint is on the very tip of the nose.
details were done with a fine and medium sharpie pen and with trim monokote. I wanted to avoid any extra weight and chance of something breaking off so I used the marking pens instead of 3d details.

Fins are 1/16" lexan with lightening holes in the root tab.
For the front/back fins I put yellow trim to simulate the...Continue Reading
Posted by burkefj | Aug 19, 2015 @ 03:34 PM | 7,141 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...

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 the front closure. 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. Also, due to the forward closure lip, 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 it is tightened, not on the propellent grain.

I needed something the...Continue Reading
Posted by burkefj | Aug 18, 2015 @ 08:55 PM | 6,409 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 | 6,622 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 | 6,207 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