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Posted by burkefj | Jan 10, 2016 @ 07:47 AM | 4,699 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 | 5,581 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 | 5,271 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 | 5,520 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 | 4,948 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:

http://www.youtube.com/user/burkefj/videos

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 | 5,978 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


Frank
Posted by burkefj | Nov 03, 2015 @ 12:03 AM | 6,065 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 | 6,954 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 | 6,483 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 | 5,870 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)



Frank
Posted by burkefj | Aug 11, 2015 @ 04:44 PM | 5,999 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 | 5,671 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 | 6,078 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 | 8,844 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 | 7,794 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.

Frank
Posted by burkefj | Feb 18, 2015 @ 01:45 PM | 7,553 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: https://www.commonsenserc.com/produc...oducts_id=5940(may 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 | 7,527 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 | 7,537 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 | 7,154 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 | 7,706 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