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Posted by burkefj | Feb 25, 2015 @ 04:37 PM | 8,452 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 | 7,490 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 | 7,297 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 | 7,277 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 | 7,283 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 | 6,841 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 | 7,430 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 | 7,459 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 | 6,709 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.

Frank
Posted by burkefj | Aug 10, 2014 @ 08:50 PM | 6,816 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)


Frank
Posted by burkefj | Feb 03, 2014 @ 01:55 PM | 6,451 Views
Links to current build threads in my blog:

ME-163 Rocket glider: http://www.rcgroups.com/forums/showthread.php?t=2356237

X-20 dyna-soar with titan booster: http://www.rcgroups.com/forums/showthread.php?t=2279007

Bachem Natter: http://www.rcgroups.com/forums/showthread.php?t=2223721

F-8 Crusader: http://www.rcgroups.com/forums/showthread.php?t=2086367

F-4 Phantom: http://www.rcgroups.com/forums/showthread.php?t=2077572

Mig 21: http://www.rcgroups.com/forums/showthread.php?t=2074615

F-105 Thunderchief: http://www.rcgroups.com/forums/showthread.php?t=2070554

F-102 Delta Dagger: http://www.rcgroups.com/forums/showthread.php?t=2066256

F-106 Delta Dart: http://www.rcgroups.com/forums/showthread.php?t=2065122

B-58 Hustler: http://www.rcgroups.com/forums/showthread.php?t=2021090

Spaceship one: http://www.rcgroups.com/forums/showthread.php?t=1795225

X-15 Delta Configuration: http://www.rcgroups.com/forums/showthread.php?t=1792770

Bomarc: http://www.rcgroups.com/forums/showthread.php?t=1769794

Upscale AGM-86 ALCM: http://www.rcgroups.com/forums/showthread.php?t=1756579

Upscale Tomahawk: http://www.rcgroups.com/forums/showthread.php?t=1743732

Space Battleship Yamato: http://www.rcgroups.com/forums/showthread.php?t=1579638

Upscale Bomarc Missile: http://www.rcgroups.com/forums/showthread.php?t=1567930

Large InteR/Ceptor: http://www.rcgroups.com/forums/showthread.php?t=1563544

X-3 Stilleto: http://www.rcgroups.com/forums/showthread.php?t=1561446

Large X-15: http://www....Continue Reading
Posted by burkefj | Jan 27, 2014 @ 12:53 PM | 8,072 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 | 8,548 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 | 7,756 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)


Frank
Posted by burkefj | Jan 06, 2014 @ 06:36 PM | 8,202 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 | 7,935 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
www.dynasoarrocketry.com

Included:

Airframe pieces with carbon spars, elevons (pre-installed)
Control Horns
Nose weight
Pushrods
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
Posted by burkefj | Dec 31, 2013 @ 12:22 PM | 6,825 Views
Well, my son got his learners permit so I had him drive down to the Evergreen Aviation museum for some practice, got in some flight time on my dart at the RC field there and took some photos of the Dart they have. Right next to it is a dagger, and while I like the dart a bit better, I figured I could modify the airframe slightly of the dart, keep the same wing/CG and create a dagger as well. I've got the plans and parts done and cut out, it took a bit more work, and some extra pieces. The canopy is moved back and the nose portion is relatively longer. The tail and speed brake shape are different. I created some wing strake pieces and the tail strakes as well.

For the rear engine humps(my name) they lined up perfectly with where I wanted my motor mount so they posed a bit of a problem. I finally wound up laminating two 6mm pieces with just the outer ones having the extensions and they sort of surround the microjet motor.

Plans are on the plans page.

12.5 oz rtf with the same components I used on the six.

...Continue Reading
Posted by burkefj | Dec 29, 2013 @ 07:00 PM | 6,725 Views
I've always wanted to do a dart, but there have been a lot of them and so I never got around to it till now. This takes a single sheet of 6mm 26.5x39" depron. I used one piece of tubular 1/8" carbon rod to do the wing spar, pushrod reinforcements, and nose reinforcement. No other carbon needed.

You simply print out the plans making sure they are not scaled and you are using borderless printing. Then cut out the templates and mark the depron. Once you have marked the right and left fuse sides, you can cut out the intake doublers and make a left and right of those as well. Only half the wing is shown, simple flip over and trace the other side. Cut out the depron. I grooved and inserted a piece of 1/8" carbon rod in the nose running to about 3" aft and below the wing leading edge to reinforce the nose. I used 3M77 spray to joint the right and left sides. I then sanded the rounded portions of the nose and fuse/vertical stab. Once that is done you can slot for the wing. I then rounded the left and right intake doublers and glued them with 3m77 spray just above the wing slot. You can cut out for the motor tube if you are makiing a rocket glider, or cut out to fit your motor. If you are mounting the motor on a plate you should put a small piece of carbon rod in the middle of the motor plate and drill and glue that into the tail to give it some strength. Make sure to leave clearance for the prop to clear the speed brake extension.

I then did all...Continue Reading
Posted by burkefj | Dec 29, 2013 @ 06:47 PM | 2,486 Views
Here is my V-1 Buzzbomb rocket boosted RC glider,as a kit offering. 39" long and 26" wingspan, weight RTF is 11.5-12.5 oz and designed to fly on the aerotech reloadable 24mm D-7, E-7 and E-6 rc reloads. This will also fly quite well on the old D11P plugged motors. Or the Quest D5P motor available from Apogee components will work with appropriate adapter or taping it to fit.

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.

Included:

Airframe with carbon spar and full flying tail surfaces installed
Nose weight
Pushrods
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:
Receiver
BEC(voltage regulator for receiver/servos)
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 foam safe CA+ and accelerator.
Depron...Continue Reading
Posted by burkefj | Dec 22, 2013 @ 03:18 PM | 6,550 Views
Flight video
Scratch built V-1 Buzzbomb RC pusher parkjet (4 min 7 sec)


I've been slowly going through some of my less flown rocket gliders to convert them for pusher so i can give them some more flight time. Normally this means a slight modification of the motor clip to use my grayson microjet V-3 that is mounted on an adapter. I have to swap a 20a esc for the BEC, and install the motor wires back to the rear and then re-balance. Most of the time I can just use an 800mah 3s pack for this motor on planes up to 16 oz. I normally use a 8002s pack for rocket boost and have the CG set for that, and with the pusher and the 3s pack I normally only have to add a quarter ounce or so to get the CG back to spec.

I decided to modify my Buzzbomb but thought a tractor setup would be better since I wouldn't have to trim the rudder to clear the prop if I did it as a pusher. I considered doing a tractor in the front of the pulsejet pod but there wasn't enough prop clearance in this small of a model(I had done it that way on my larger buzzbomb back in the day).

Well, it was a very interesting day yesterday. Really strange behavior, like it was tail heavy. Had to run it very nose heavy to get any control at all. Had all sorts of adverse yaw in banks. I tried all sorts of down and right thrust and it was slightly better. Finally upon suggestion I tried a bit of aileron reflex and it got better, but still wasn't flying normally. I finally concluded that the rotating...Continue Reading