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Archive for December, 2017
Posted by burkefj | Dec 26, 2017 @ 06:29 PM | 9,465 Views
Another scratch build I've been thinking about for a long time came to fruition over christmas. I got three very nice flights today on the Viper. Just need a fine tweak of down trim for boost, and a slight bit more up trim for glide than my initial settings. Given the small wing area and 11 oz glide weight, It flew much better than I was expecting, not a long glide, but very nice none-the-less and had plenty of pitch control down to flare on landing, very nice! Here are the three flights in order starting with the maiden flight.

I used model plan foam for the wings, lightweight 2.6" tubing and an angle cut plastic nose cone, 29" long, 23.5" wingspan and 12 oz rtf weight.

RC Colonial Viper RC Rocket Glider (1 min 5 sec)

...Continue Reading
Posted by burkefj | Dec 19, 2017 @ 02:08 PM | 10,036 Views
Here's another that I've been mulling over in my head, converting the original rocket design into an RC rocket glider. This design was an Estes rocket themed in 1950's -ish flash gordon/Buck Rogers sci-fi style that was supposed to be a galactic pirate ship with a dragon theme. I used 2.6" lightweight tubing, 23.5" wingspan, 34" length, 11 oz rtf with rocket motor. It's got 235 sq inches of wing.

I built the cockpit box out of depron, as are the vertical stabs, and the wing is MPF with a single 1/8"spar with elevons. I played with openrocket to evaluate the lateral stability with the forward vertical stab and determined the placement to give me margin, then adjusted the wing shape and location to minimize nose weight needed. The cockpit is just an opened bottom box that I then sanded to contour using sandpaper over the body tube. Then I cut the notch in the forward vertical fin to fit the height of the box. Vertical stab goes through the rear of the wing and body and has a notch for the motor tube, and the motor tube has some locating strips on either side to center it laterally.

I like steampunk things, but not enough to build them myself, but this sort of has that feel. I left it white because the original markings tend to pop more than when on gray/silver. I hand cut the vinyl in red and then used black strips to make the dragon wing accents. For rivets, I make a 12" strip of milk jug plastic and make holes every 1/4"...Continue Reading
Posted by burkefj | Dec 08, 2017 @ 04:43 PM | 7,055 Views
I did the wing a flat plate, with just the motor pods mounted under the wing tips, and a modified front bridge/pod that is flat on the bottom to allow the rail guides/rail to clear the bottom. A 24mm motor tube will go from rear into the front bridge, and allow the wires to route through to the receiver/1s battery in the bridge with a small plate on the bottom to cover it up made of styrene. The 24mm tube will have a coupler the full length inside to reinforce it. This will be adaptable to a pusher parkjet if desired as well.

I've cut the pieces out, 29" long, 23.5" wingspan, around 11" at the root. I'll have an angled plate on top of the 24mm tube to give it the tapered look. I did add a single vertical stab for stability.

Here's what I'm using for the initial flight CG

http://wingcgcalc.bruder.com.br/en_U...d6=0&sweep6=0&...Continue Reading
Posted by burkefj | Dec 02, 2017 @ 01:32 PM | 5,206 Views
I wanted to do an orbital transport glider for a while, but buying a bunch of BT-80 tubing and cones for my kits finally pushed me over the edge. This is based on the late 60's Estes Orbital transport that had an SST style booster the recovered under parachute, with a biggyback glider that was freeflight. The glider had a low mounted wing that had a lot of dihedral for stability in free flight. The elevons were angle cut and were bent up for glide, and the drag was calculated in the stack to give a straight boost.

For a standalone glider that boosts vertically I didn't want a low mounted wing with dihedral, I prefer a mid mounted wing to get the servos on the bottom but up away from landing damage. Based on the dimensions I was able to just re-use the same wing I use for the Hypersonic III, Jayhawk, and Marauder kits so I had a known good CG location. It went together really quickly, and I hand cut the vinyl trim using what I had laying around. I used standard straight elevons and just mocked the angled wider tip elevons with trim vinyl and some sharpie markers to give it that "orbital transport" look. I added some leading edge color since it was a bit plain, and added a stripe on the bottom to remind me what direction I should be pointing

CG just needed .25 oz of nose weight, so AUW ready to fly with E-6 is 10.25 oz. 2.6" diameter, 32" long, 20" wingspan.

Maiden flight was perfect, hands off and glide was perfect as well, here is the maiden...

Maiden flight of Dynasoar Rocketry Orbital Shuttle rc rocket glider (1 min 46 sec)