Thread Tools
This thread is privately moderated by burkefj, who may elect to delete unwanted replies.
Dec 08, 2017, 04:43 PM
Registered User
burkefj's Avatar
Thread OP
Discussion

Klingon Battle cruiser...RC Rocket Glider and Pusher Parkjet


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&
Last edited by burkefj; Jan 19, 2018 at 05:33 PM.
Sign up now
to remove ads between posts
Dec 11, 2017, 02:22 PM
Registered User
burkefj's Avatar
Thread OP
Made more progress, laminated the rear block, glued on the angle plates and vertical stab, laminated the motor pods and rounded them, laminated the LE doubler and glued the motor pods on. So far, foam and carbon is 4 oz, receiver, rocket motor, battery and wiring/servos is 4.25 ounces, hoping I can adjust the neck length for optimum cg without nose weight and come in with 10-11 oz rtf, tubing for the neck will be here today.
Dec 12, 2017, 11:01 AM
Registered User
burkefj's Avatar
Thread OP
Finished glide tests with CG at 16% mac for boost. AUW rtf is 10.25 oz boost and 9.25 oz glide weight.

I adjusted for length of the neck to minimize nose weight and maximize strength. Turned out I needed to add some little rear side plates on the fuse to keep the wing supported on landing, the main landing stress will be on the motor pods, but the wing was sagging in the middle when sitting on the ground a bit too much. Added a wing skid on the front to keep the nose off the ground. When all was said and done, putting the rx and battery in the nose was too nose heavy, so I mounted them under the wing against the fuse and just added 1/2 ounce of nose weight in the nose. I'll glue the bottom plate once I've determined if CG is good.

Hoping to try a flight or two today.
Dec 12, 2017, 06:08 PM
Registered User
burkefj's Avatar
Thread OP
Flew this afternoon before lunch. Cold but dead calm. Took two flights to get the boost trim right, needed just a bit of downtrim, I put in too much for the second flight. However glide trim and CG were dead on, you would not believe how much this thing just floats, being basically a flying wing that is running nose heavy, it does run out of flare for nose up landing, it just lands horizontally, but the decent rate and speed is so slow it is not an issue at all. I'm pretty stoked.
Dec 13, 2017, 02:26 PM
Registered User
burkefj's Avatar
Thread OP
Finished it up, paint added 1/2 ounce, needed 3 grams in the nose to re-balance, so 10.75 oz rtf.
Dec 13, 2017, 04:59 PM
Registered User
burkefj's Avatar
Thread OP
Klingon Battlecruiser RC Rocket Glider (1 min 19 sec)
Last edited by burkefj; Jan 19, 2018 at 05:56 PM.
Dec 14, 2017, 10:14 AM
Registered User
Cool project, good build thread
Jan 19, 2018, 05:37 PM
Registered User
burkefj's Avatar
Thread OP
Here is the original rocket glider converted to a parkjet version, For the parkjet version I kept the inner tube liner the same length as the outer body tube and mounted a 1/8" ply plate to the rear of the tube combination to mount the motor. I used a talon 15 ESC and a grayson microjet V-3 using an apc 6x4 prop. The talon only weighs about 7-8 grams with wires. I used a 3s 800mah venom/eflite 25c battery velcro'd under the wing next to the fuse at the LE. I put the CG about 1/4" forward of the rocket glider boost CG, It required just .75 oz nose weight and gave a 14 oz rtf weight.

Flew it today, handlaunch was easy, even in some 5-8mph wind, flew really nicely, slight nose up, decent roll rate, split esses, big and small loops, slow flight, wiggled the wings when too slow, no bad stall issues, landing power off into the wind was a nice easy decent rate to a flat landing. I'm pretty pleased. 4 minute flights were easy. Although the wiring looks a bit cluttered in the pic, in flight you don't see it or the battery, it gives a very Klingon outline in the air.

Plans are at: https://dynasoarrocketry.com/?page_id=1226
Last edited by burkefj; Jan 21, 2018 at 02:23 PM.
Oct 19, 2018, 10:43 PM
BEC
BEC
Registered User
BEC's Avatar

Another Battle Cruiser


I got one of Frank’s kits for the Battle Cruiser and built it as my very first RC rocket glider. First three flights, all on Aerotech E6RC motors, were today. Boost was a bit squirrelly on the first flight (overcontrol on my part). After that - pretty durn cool.

After flying it again at the club launch tomorrow I hope I’ll get it painted before the normal weather comes back to the Pacific Northwest.

(It did help that I’ve gotten some air time on a couple of RC airplanes recently - my old standby Mountain Models EZ Scout, and also I built one of Flite Test’s Simple Scouts since my son and grandson have been messing with fixed wing stuff of late.)

Picture is on the pad before the first flight.


Quick Reply
Message:
Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Build Log BBCC8-Douglas F4D Skyray-Jetex FF to Rocket-glider RC builderdude Balsa Builders 191 Feb 15, 2019 06:57 PM
Discussion Pegasus RC Rocket Glider from Arkansas [Dynasoar Rocketry] crawf56 Rocketry 20 Mar 05, 2017 11:35 AM