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burkefj's blog
Archive for October, 2012
Posted by burkefj | Oct 22, 2012 @ 01:14 PM | 6,847 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 | 9,703 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-100
F-101
F-102
F-104
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
Buran
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
Goblin
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 | 6,837 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 | 7,914 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 | 7,948 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 | 2,641 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