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Posted by burkefj | Dec 25, 2012 @ 09:46 PM | 9,111 Views
Thanks to my lovely family who got me enough foam, and electronics to make another rocket glider. They also gave me a half a day repreive yesterday and today to work on it. I've been wanting to try a spaceship one , but have been worried about CG, twisting and stiffness of the tail booms. It came out ok, I wound up having to put some parallel stiffeners on the bottom of the wing to help prevent twist.

I couldn't find a decent 3-view that I liked or thought was right, so I just did this freehand from a book I have from pictures and relative sizing. I think it captures the look if not perfect scale. The full flying control surface placement was dictated by the fact that I wanted to put the pivot rod accross the fuse and tie it in just in front of the rocket motor mount. This helps reduce the twist of the tail booms and worked well, and actually came close to where they are supposed to be. Since I was doing a cruciform structure, I had to move the wing placement to the middle of the fuse instead of the upper portion, but I don't think it makes that big of a difference in look. I did not add the later stub strake fins in front of the control surfaces yet till I fly it and see how it does without them. Due to the lack of stiffness of the booms, I glued in carbon tubes in each one and laminated a 3mm cover over the tube, that made them very stiff. The wing still had some twist so I used two carbon tube spars as well.

I mounted the servos as far forward as I could to...Continue Reading
Posted by burkefj | Dec 20, 2012 @ 11:47 PM | 8,902 Views
I decided I wanted to try doing one of the proposed Delta wing configurations for the X-15-3 plane, I chose the one normally modeled with the diamond wingtips...I made it simply by taking my X-15 plans, stretching the fuse the scale amount(about 10 inches) and changing the top view to a delta with wingtips. I added some 3mm covers on the sides of the fuse to sort of give it a look like the fairings had. It gives it a bit more body. It's all completed except for painting now, and the fairings added quite a bit of stiffness to the body. It came out at 55.5" long and about 21" wing span which is slightly oversized just for wing loading. Weight is right at 13 oz rtf, but without paint, so assume about an ounce more finished.

It's my first try using the hobby king 5a bec and the orange spektrum compatible rx...so far so good...

Update 12/21/12 Since the world didn't end yet, i had enough time to paint the Delta X-15 and do the markings. Came right out at exactly 14 oz rtf. Pictures show it next to the X-15-2 and also next to my Icarus...

Update 12/27 Good maident this morning. CG and throws were spot on as was glide trim, very nice!
Here is the cg calculator I used:


Flight video near the end of this link:
Spaceship One and X-15-3 Delta Configuration RC Rocket boosted gliders (0 min 0 sec)

Posted by burkefj | Nov 13, 2012 @ 02:32 PM | 9,020 Views
I've updated my Bomarc plans to reflect the A or B model wing/ramjets. I redesigned the ramjets to not have an X form but just double of the side view and it looks like it will work fine and weigh the same. I think it makes a cleaner look. I built this one as an A model with the wing and pods moved back and AUW rtf is 11.3 oz with an E-6RC motor.

Doing the ramjets by doubling them allowed me to round them more and it gives a better shape, I think.

I did the markings on the pieces/painting first before assembly and was very careful with the CA when applying to avoid running the marker lines. I used model master "titanium" for the ramjet rear ends, and some Q-tip shafts for the pitot/counterbalance probe thingys...

I used styrene sheet on each side of the fuse to support the rail buttons as well as give something solid to drill and glue to when attaching the ramjets.

I also added styrene strips to the bottom of the ramjets to help them survive landing rash as well as the underside of the nose, and used contact cement(uhu por) to attach it. I don't indicate that in the plans, if you land on trimmed grass it probably isn't necessary, but I already had the styrene on hand.

I did this one in a slightly different white color scheme I found with a black nose and use sharpie pens to do the panel lines/accents, sig stars and bars and vinyl letters from Office Max.

Build time was approx 8 hours including cutting plans, dry fitting, markings and finishing.

Test flight in 8 mph winds was good, boost was vertical, just a bit of weather cocking at the end of the boost that was easily adjusted back to vertical. Glide setting was fine. This is using the same relative CG position (relative to the wing LE where it hits the top view fuse profile) as the B model. IE mark the wing as shown on the plans for CG, move the wing back to the A model position and the same CG markings will apply.

Plans are updated on the plans page.

Posted by burkefj | Nov 07, 2012 @ 06:09 PM | 10,164 Views
I was on a business trip and was able to stop by the White sands missile range and the alamogordo space museum. I have to say that seeing a bunch of those rockets and missiles I have built models of was really exciting. I was able to actually touch a Pershing and Bomarc Missile The Talos is a huge missile. Hopefully you will enjoy the closeup shots. They had their V-2 refurbished and it is one of the most complete V-2's in existance. They had it made into a cutaway so you can see the internal structure and tanks, etc. They had some of the V-2 skin left over and were selling it mounted on a base, so I bought some real german December of 1944 V-2 skin I'm such a dork. Really, I'd encourage anyone in the area to go to the white sands missile park, it was outstanding.

...Continue Reading
Posted by burkefj | Oct 22, 2012 @ 01:14 PM | 6,826 Views
I decided to try a 1.5x upscale of my full fuse AGM-86A ALCM, I think by using a KF airfoiled Wing and since the fuse is hollow with formers and skin, the total AUW won't be more than 2.25X the original, which would mean I could potentially fly it on 24mm F-32's or 32mm F-16 or G-12's.

Wings are built with launch rail attached, and full flying stabs are built and laminated.

Update 10/28 Cut out the top and side views and tab and slotted them, installed the motor mount, thrust plate, tail torque rod and vertical reinforced with carbon and laminated with 3mm depron.

Update 10/29 Added the formers and lightening cuts, and cut and fit the top nose plate(not shown). Just need to add strips at the top and sides to attach the sheeting to.

Update 10/30 Added the strips and added the rear sheeting after installing all electronics and the wing. Added in the hatch for the battery and did an initial CG check. AUW is leaning towards 30 oz RTF with a 4.6 ounce F-16 32mm reload. CG looks attainable with only about 2.5 oz nose weight. Just need to add the forward sheeting, sand and apply markings.

Update 10/31 All finished. AUW is 30 oz rtf with an F-16, about a half an ounce less for an F-23 or an F-26FJ.

Update 11/19 Maiden flight was great on F-26FJ, flew two flights, hands off boost, nice glide.

Large ALCM AG-86A Cruise Missile rocket boosted RC glider (1 min 33 sec)

...Continue Reading
Posted by burkefj | Oct 19, 2012 @ 01:56 AM | 9,679 Views
Below are almost all of the scratch builds I've done. Rocket boosted at the top and pusher parkjets below. If there is something here that you really are interested in, let me know and I'll see if I can get you a pdf of the plans/templates if I made them.

Here are some results of how the models flew, out of 64 built, just a few failures, and a few that had initial flight problems but were solved...If there are no notes, they flew fine off the board.

Avro Arrow
X-15: 5 versions, aileron/tail, taileron only, Full fuse, Delta configuration. 72" 29mm version
Small F-106
Large F-106
F-105 Small and larger
F-107 Ultra Sabre
XF-92 Dart
F-4 Phantom
Bomarc: 4 versions, A model, B model, 29mm 72" B model, 68" A model for G-12's
Bomarc A: with ramjet tractor motors, too heavy for 24mm motor, motor thrust was marginal on tractors, wind blew pad over on last test flight and destroyed model
XF-91 thunderceptor: Used 18mm and 24mm airstart plus pusher, worked great.
Space Shuttle
Saab Draken: flew great, rolled like a drill, killed when a spektrum lockout occured when pointed straight down...
Interceptor(3 versions, two smaller 24mm and one 72" 32mm version)
Jayhawk(2 versions, 24mm and 72" 29mm version)
Mach 10
Mach 10(upscale): Suffered wing flutter and destruction on test flight
Flapjack: Used differential throttle for yaw control, flew great
A-4B(2 versions)
B-58 Hustler
ME-163 Komet: Flew...Continue Reading
Posted by burkefj | Oct 07, 2012 @ 09:27 PM | 6,814 Views
I finally got around to upscaling my Jayhawk target drone 1.5x. 30" wingspan, 71" long. Used laminated 6mm sheets with staggered joints, and hs-65 mg servos with carbon reinforced wire pushrods to get the servo weight forward. I inset the nose weight into the nose section before gluing the pieces together so it is hidden. Just a single carbon tube for the wing spar, and some styrene sheet for reinforcing the bottom where landing scrapes would happen. The wingtips are slotted half way and plug into wing tabs. Turned out nice and stiff and the AUW is right at 35 ounces, same as the X-15 but with more wing area. Since this is an upscale of the original, the wing area is scaled proportionately, which means the wing is larger than scale, this is mainly to get the flight CG ahead of the lateral CG so I don't have lateral stability problems.

I like the C model because it isn't all red which allowed me to leave some of the depron unpainted to save weight, and it looks a bit different than all the others out there. Decals I made due with what I had and took some artistic license and used my sharpie for panel lines.

Right around 1000 sq inches of area.

I've found that the vinyl doesn't want to stick to the testors paint, so I had to use 3m-77 spray on them and then attach them, takes more time and you have to be more careful.

Maiden flight was great, I've settled on the Aerotech 29mm SU F-26FJ, boost isn't terribly high, but it is nice and straight and...Continue Reading
Posted by burkefj | Oct 04, 2012 @ 04:03 PM | 7,897 Views
Some great pictures by Gary Goncher from the Fillible's Folly launch near Amity Oregon this last weekend. Included are my large X-15, bomarc, Interceptor, small V-1 buzzbomb and my level 2 cert flight on a performance rocketry 4" nike smoke and J-350 as well as the first flight of my Pershing 2 on an H-123 with separate nose/body chutes.

Also included are flights of the Nike Smoke on an I285 Redline, and my Pershing 1A on a G-75 metalstorm and Pershing 2 on an H-123 from the Rocketober launch in Brothers, Oregon....Continue Reading
Posted by burkefj | Oct 04, 2012 @ 02:35 PM | 7,931 Views
Wanted to post a bit about my rocket powered glider designs and things that I think about when building them.

On the surface, profile depron planes look simple, and a lot of people disparage them because they don't look real(in their eyes....) They are simple conceptually, but that takes some work to make them simple, strong and have good flight performance. In general cruciform designs will give the highest surface area and strongest structure for the weight. They have low frontal area and low drag. By using a cruciform type structure, you can get things to fly with extremely small wing area, but due to fuse lift, have very light loadings, very gentle flight and landing characteristics. I have done several full fuse designs, and they look great, however flight performance and weight is not as good as the profile designs, it all depends on what you are trying to achieve.

I like rockets that look like the original, ie motor in the tail, I'm not a pod and boom person, although that is the easiest way to combat CG shifts and get good flight performance.

I like to keep things simple, which means not having to move balast, centerline thrust, and minimal control surfaces. I normally run flat plate wings. The advantage of this is that you can boost perfectly straight up and not have any pitching moments, all you do is keep it straight if it strays due to wind, and then pitch over into glide. You don't need a special launch pad.

I like full flying tail designs. By...Continue Reading
Posted by burkefj | Oct 01, 2012 @ 05:28 PM | 2,622 Views
We had perfect weather this weekend in Oregon for our highpower launch near Amity and I took a literal Van load of rocket gliders....Pretty much everything shown here. Got in 16 flights over two days, some great flights with my Big X-15, Interceptor and Bomarc getting a flight in each day! I have to say the big gliders really look impressive and are really easy to fly.

That got me motivated to use the last of my store of depron sheet and servos/receiver, so I decided that the best candidate would be to upscale my Tomahawk cruise missile.

Advantages are, it is long, and not too wide, to keep weight down, double ply would be all that would be needed, with single ply wing with spar and KF airfoil by reinforcing the leading edge 25% with a doubler up to the spar. Two megal gear HS servos running the full flying tail and a 32mm motor mount.

Update 10/1: So far the AUW is looking like 24-25 oz which should fly on the Aerotech 32mm G-12 motor, but a single use G-38 weighs the same and would work if the model winds up heavier than 25 oz.

I have it framed up ready for sanding, 10.5 oz airframe with tail pivots, 4.5 oz motor, 1.5 oz servos, bec and rx, 1.5oz battery, and maybe 3 oz nose weight, an ounce for glue and styrene reinforcement plus launch button rail..22 oz plus any paint/trim...1.5x upscale so 60" long, 30" wingspan....Given the area, wing loading should be in the 6.5-7 oz per sq foot range.

Update 10/2: couldn't sleep so got up and applied the trim...Continue Reading
Posted by burkefj | Jan 22, 2012 @ 11:44 PM | 4,645 Views
This is one of my favorite cartoons when I was a kid. Always wanted to make a flying "Argo" from Starblazers.

Here is the progress so far, got the profiles made, trim monokote applied this time instead of paint, applied the details with a sharpie. Dry fit the pieces together.

Length is 45 inches, wingspan is 20 inches, dry fit weight is 6 ounces.

Came out at 12 oz rtf with E-6 rocket, two hs-55's, spektrum rx and 1.5 ounce battery and 1 ounce nose weight.

Update 1/25/2012

got in four test flights today! It was just a bit tail heavy on the first three flights and the up trim was a bit too much for glide. I moved the battery forward and adjusted the trim for the final flight and it was great.

Here's the video.

Scratch built Starblazers Space Battleship Yamato RC rocket boosted glider (1 min 18 sec)

Posted by burkefj | Jan 04, 2012 @ 02:49 PM | 8,013 Views
Started this this morning, an upscale of my bomarc pusher or rocket boosted glider, this will be for 29mm rocket motors.

The nose looks a bit short since the top view is not on the centerline of the fuse, due to the high mounted wing, the side view nose will be another foot longer. Length will be about 80 inches, and wingspan 30"

Update 1/08/2012 Finished the ramjet pods, with carbon rods installed to go through the fuse and styrene skid reinforcement. I wanted to keep the air flow through the ramjet pods to reduce drag, so I left the front tapered portion profile and did an xform support for a thin bt101 tube for the rear portion, and wrapped them with chrome monokote. I think it will give the right look but still be fairly light. The body tubes added almost 4 ounces of weight.

I made a 12" spruce bar to mount the rail buttons on and installed them into the fuse with carbon rods to glue into the fuse for support. I then laminated styrene sheet on both sides to support it and to act as support for the ramjet mounting rods to go through. It seems pretty stiff. Ready now to slice the top fuse and slot and tab it and attach to the top view.

Update 1/09/2012, finished it except for the tan nose. Total weight with balast and motor rtf is 39 ounces. Looks like it will be a candidate for G-33's.

Update 1/11/2012 Test flight success! G-40 was a bit hard, the G-33 was a better boost, glide was pretty good, it was windy and the model wanted to bind on the...Continue Reading
Posted by burkefj | Dec 28, 2011 @ 12:09 PM | 8,218 Views
I still wanted to see if I could build a tail boosted glider that could work without balast shifting and use the G-12 32mm motor. I decided the best platform an upscale of the Estes Interceptor. The original RC/RG I built was 42" long and used an E-6 and weighed 9 oz rtf. I decided to just go with a single ply top view, except doubling it at the rear for the motor mount, and adding a kline-fogelman(KF) step on the wing bottom to help stiffen it, hide the spar, and generate a bit more lift. I used double ply 6mm for the fuse, however it is only 4" accross so about half of the x-15.

WS is 34" and length is around 75"

Here is how it looks so far.

Update 12/28 Completed the build, with all electronics and a bit of ballast installed it is at 17 oz. Battery will be 1.5 ounces and motor 4.4

Update 12/29, finished the markings and CG. AUW is 23 ounces with motor and battery. Did most of the markings with sharpie for panel lines, stars and bars from sig, vinyl letters from coverite, and the rest is trim monokote cut to fit. I decided to put some fake gear doors and flaps etc and some gun ports. I had some random military plane placards from an old trim sheet I had, so I used those.

Update 1/07/2012 Got in a perfect test flight on a G-12, really docile on boost and trivial to land, just a little wing wobble when too slow, but no stall.

Launch video at:

Scratch built six foot tall Interceptor Rocket boosted RC glider (1 min 32
...Continue Reading
Posted by burkefj | Dec 24, 2011 @ 11:13 AM | 4,880 Views
I got tired of sanding on the X-15, and was staring at the ceiling, and got the bug to rework my X-3 into a cruciform style and rocket motor. Originally I had done the fuse as pure profile which worked fine for stiffening the stinger for the pusher motor, but now with rocket motor, I could put the motor more forward at the motor exhaust area and use a top view as well and save weight.

I also wanted to just use full flying tail instead of aileron/elevator to save one servo, and had to do a bit of creative stiffening of the tail using some carbon and basswood supports, and by running my pushrods inside carbon tubes to allow me to push them more forward. I was worried the stiffness of the tail would be an issue but turned out it flew perfect off the board. The CG was more forward than my fuse only version which only helps lateral stability which I had an issue on on the first flight of my profile only model.

Only needed one test flight. Since I had the tail mounted high I was worried that the roll would be off axis, but this didn't turn out to be a problem. I had my boost trim slightly off as it pitched toward the spine, but was easily corrected and trimmed out at the top. My glide trim was spot on and it was nice and easy. Pitch was very responsive and I over-flared to a "plop" down landing

Posted by burkefj | Dec 21, 2011 @ 03:43 AM | 8,248 Views
I decided to do an upscale of my X-15. The tail pieces are also laminated 6mm grooved with the torque tube inside. Fuse is two pieces of 6mm spliced and laminated. The top view has a 1/4" spar hidden in the laminated pieces. Took 3.5 sheets of 6mm and 3 sheets of 3mm. Total airframe weight is 18.5 ounces.

Update 12/21 Slotted and tabbed the fuse/wing, mounted the rail buttons on a spruce slat inlayed into the side, laminated some styrene on the nose and tail for landing skids, mounted a 29mm mount and got the bottom glued in place.

Just need to round the edges of the wing and top fuse, glue on the top fuse and install the electronics.

Update 12/26, finished the model and electronics install:

Got in two flights today. First flight on a G-25 was majestic, it chuffed a couple of times like they tend to do, and then a nice graceful boost to around 600 feet, pitched over and hit the glide trim, and it was perfect, nice and slow and plenty of authority to flare for a tail first touchdown.

The second flight I liked a bit better on a G33, much more growl and faster boost, again arrow straight, pitch over and nice glide. The 6' rail worked perfectly.

All in all, I'm very happy and will now do the painting and panel lines. Thanks to John for digging the motors out of the archives/vault. Only got one cell phone picture that is blurry on the G-25. I think the perfect motor will be a G-40.

Update 12/29/2011 Finished painting and applying panel lines with silver...Continue Reading
Posted by burkefj | Dec 14, 2011 @ 01:11 PM | 10,034 Views
For an article I'm writing, i re-drew my x-15 plans to have a slightly larger scale, but still fit on one sheet of depron, made the wing and fuse outlines more scale, along with the tail surfaces. I chose a flight profile where they didn't have the rear end box, and did not fly with the ventral in place. I also added a step by step instruction sheet in the plans as well as doing some build photos. It also has a parts list and flight notes/control throws.

I've flown this on E-6 rc reloads, E-9 and D-12 estes motors where I removed the ejection plug and charge, and re-plugged the ends with epoxy and they all flew it well. The D-12 wasn't super high, the E9 has a pretty quick boost, but doesn't go as high as the full 40ns E-6 motor. All the boosts were very straight, with just minor pitch adjustment as it got affected by wind on the way up.

It is a bit heavy for a quest D-5, and did not want to clear the rod, so I don't recommend that motor. Aerotech E-15's single use motors may be a little hard accellerating for the full flying tail, so you'll want to have a heads up if you fly it the first time on this motor to be sure you won't get any flutter.

The D-9 was the heaviest motor, and I had the battery fully forward for that flight, and have a long strip of velcro so I can move the battery back an inch to an inch and a half for the lighter setups, the glide profile was good, about 10 degrees down with post boost trim, and maintained good flare till right before...Continue Reading
Posted by burkefj | Dec 07, 2011 @ 02:37 AM | 5,331 Views
Well the X-37 didn't work out too well, and I hated looking at a failure, and I hated to waste the nice rounded fuse I made, so I chopped off the rear end, reprofiled the nose, added a new rear former and motor mount, a tail, cut lightening holes in the bottom of the old fuse, cut off the wings, made a new wing, and glued it to the fuse. It is now a close scale Buran

It will also allow me to get a more rounded nose and bottom front.

Looks like it has a slightly more rearward CG than my shuttle, and is about a half to an ounce lighter.

Here's the flight video from this evening, I had to pitch forward to keep it out of the low fog...

Scratch built Russian Buran shuttle Rocket boosted RC glider (1 min 14 sec)

Posted by burkefj | Nov 28, 2011 @ 01:45 AM | 6,838 Views
I've been secretly working on a space shuttle over the holiday, in between working on my 72" tall Pershing 1A rocket.

I'll be posting pics and progress as I go along. 26" ws and 35" long, approx 13.5 oz rtf planned.

This will be a full fuse, cockpit will be laminated depron sanded to shape and nose will be a two angle piece to give it an approximate shape, because I'm too lazy to do a multi piece compound curve and am trying to keep it simple. The rear oms will be a tapered half round to give an approximate look, but is not meant to be an absolutely correct scale profile.

The only carbon is the wing spar 1/8" carbon tube, and 1/8" carbon strip to stiffen the vertical tail.

I added formers to aid in getting the payload bay shape and also added depron strips to help locate the fuse sides in place.

I'm using some rocket nose cones cut off and glued on to the back as placeholders for nozzles till I find something the right size or make something better.

Made more progress last night, finished the other side. I was really not happy with the cockpit so I re-worked it using four pieces of 3mm depron, two sides, a wraparound, and a cap. It looks much better. I also discovered that the 3-view I had used was really crappy, and I reworked the OMS rear end a bit.

I also did some of the markings using trim monokote and will only need to paint the bottom flat black, and use a flat overspray over the monokote.

****Reflections and Notes******

I'm sort...Continue Reading
Posted by burkefj | Nov 04, 2011 @ 02:26 PM | 11,370 Views
I'm re-working my profile X-20 rocket glider to have a simple fuse shape to give it a bit more scale shape. I'll post photos as I go along and eventually update the plans. I adjusted the fuse profile a bit, you could build it as pure profile or add the side/top pieces.

I did wind up adding two carbon strips to the wing sides to help with flex on landing if you come in tail first, I felt there was a bit too much and it might crack on a hard pitch up tail first landing. It is now pretty stiff. The fuse pieces fit pretty well as cut, just minor trimming for each side as needed.

I finished the frame up and rough sanding, and did a gob of inside the house test glides to get the CG range, and double checked with my cg calculator and a couple of older threads on deltas, in addition to my profile version. I found with the full fuse that the CG was about 1/4" rear of the simple profile version. It was a bit more back than I had calculated but my test glides with a 20 degree nose up mush push glide produced the desired pitch over at the rearward CG.

I did two test flights this morning, using 3/4" up trim for post boost glide to compensate for the nose heavy condition. This was my first time launching by myself so I had to hold the battery and ignition wires in my left hand, cradle the radio and get on the sticks quickly I learned an important lesson doing this, on a cold day, do not stand directly behind the model, as it pitched forward and stayed in the exhaust...Continue Reading
Posted by burkefj | Oct 27, 2011 @ 02:52 PM | 12,284 Views
I've done a build thread with photos for the Estes Interceptor profile upscale rocket glider.

AUW is 9 oz rtf with E-6 reload, I think this bird is light enough a quest 20mm D-5-P would work as would a D-12 or E-9 BP motor.

One sheet of depron will work, however you will need to splice the fuse near the back half as the length is 42" or so. You can splice wherever you wish, I did it near the rear as it is most supported by the wing/top plan.

Just one small 1/8" carbon rod for a pivot and two small 1/8" id aluminum torque tubes, two dubro servo horns for the torque tubes, a 24mm motor mount, and about 18" of 1/8" by .034 carbon strip for the wing spar. A bit of dubro hinge tape for reinforcing the spar and torque rod, two 5" .34 pushrods.

You'll need two hs-55 servos or similar, an rx, bec and 1.5oz 2s battery or similar. For pusher, you want to keep the tail light, a 1-1.5oz motor should be ok, just install an inset motor mount and mount the motor.

I built this one from printing out my own plans without margin or scaling and taping together. When cutting the tabs make sure to use your slits in the top view as your guide instead of blindly using the template to make sure they line up perfectly. The ventral and dorsal fins don't have to be at a certain angle, as long as they are more vertical than horizontal they should be fine, and should be matching.

Total build time for me was 10 hours including cutting the paper...Continue Reading