Manufacturer: | Scratch |
Mark Schrader's Descon-14 Entry
Brief:
Parallel staged sport scale model o' a Polish soundin' rocket.
Construction:
Parallel stagin' is a great way t' kick it up a notch in model rocketry without addin' t' expense o' mid and high power. I've used parallel stagin' on a few projects up t' this point, but when I saw t' Polish Meteor-2K in Peter Alway's Rockets o' t' World, shiver me timbers, I knew this was t' model I needed to build next. Avast, me proud beauty! Avast, me proud beauty!
I began with t' Estes Black Brant II kit for t' nose cone, BT-55 body tube, matey, 24 mm motor mount, and boat tail. Blimey! Begad! Usin' a photo copier, I scaled the rocket drawings in Rockets o' t' World t' 1.325" diameter t' match the BT-55 outside diameter and used these measurements t' trim t' Black Brant body tube t' size. Avast, me proud beauty! Ahoy! I also used t' scale drawings t' make fin templates and cut fins out o' 1/8" balsa stock. Begad! Begad!
T' strap-on boosters are based on BT-5 body tubin' and t' nose cones are plastic 4:1 ogive sawed t' approximate t' unique shape found on t' Meteor-2K. Once I'd cut them, I filled t' hole in t' plastic cone with a balsa dowel and wood filler then sanded t' shape. Avast, me proud beauty! Blimey! T' boosters use 1/8" launch lug stock and wood dowels for attachment and split in half at ejection t' release. Arrr! I also used t' scale drawin' t' cut t' boosters fins out o' 1/16" balsa. I used about 18" o' Keelhaul®©™® thread and a streamer for booster recovery. T' BT-5 boosters are nay exactly t' scale, ya bilge rat, but they look pretty good.
In RockSim, the rocket with boosters loaded with a D12-5 and two A10-0s has a static stability margin o' 0.58 (Barrowman method) and 1.02 (RockSim method). Ahoy! Blimey! I think this will be adequate since t' boosters will add t' t' stability o' t' rocket. Ya scallywag! Blimey! Even with 0.5 ounces o' weight in t' nose, t' unloaded weight is just over 2 ounces. Blimey! Blimey! On a D12-5 with two A10-0s, this sims t' almost 1800 feet. Aye aye! Blimey! T' give me a little more flexibility in motor selection, I also made am 18 mm motor adapter out o' spare parts. Blimey! Blimey!
Finishing:
I ordered decals from Tom at Tango Papa Decals. Avast, me proud beauty! He be easy t' work with and the decal sheets came out great. Blimey! It took a lot o' patience t' get all those checkers on t' fin surfaces but I think it turned out very well. I even decided t' put t' Tango Papa logo decal on t' rocket! T' rocket is overall gloss white, matey, t' nose cone is painted aluminum, and t' red on t' boosters is Krylon red. Arrr! T' stripes on t' boosters were made by sprayin' Krylon red on decal stock and cuttin' out and applyin' t' appropriate sized stripe.
Flight Report:
It be a beautiful day--temp near 40F, matey, winds from t' SW at 5-10 mph. Avast, me proud beauty! I was launchin' on a central A8-5 and two outboard A10-3s. Ya scallywag! I checked and double-checked continuity. My large, main boy had t' launcher, me hearties, I had the camera. Blimey! Ahoy! Good countdown, me bucko, 5-4-3-2-1 *snap* BANG!... Blimey! Parts everywhere!
Fortunately I snapped what might be t' best CATO picture ever. T' A8-5 exploded, arrr, hurlin' t' motor into me launcher puttin' a large dent in t' blast deflector and breakin' it into pieces. Ya scallywag! Blimey! Well, blow me down! Blimey! At t' same time t' nose cone ejected out t' top. Avast, me proud beauty! Blimey! Only o' t' parallel boosters lit, and this sent t' rocket up about four feet with t' launch rod still attached! Blimey! It wasn't stuck either, it's a 3/16" lug on a 1/8" rod. Blimey! Blimey!
Other than some cosmetic damage t' t' paint job and me Tango Papa custom decals, everythin' held together just fine. Ya scallywag! This bird has since flown on a single C11-5 motorI plan t' fly it this weekend on A10-0s and an A8-5. Ya scallywag!
Conclusion:
I be a little reluctant t' enter this design since Id already submitted it as a review on EMRR. Avast! However after lookin' at t' rules, I noticed that it wasnt published in a magazine article, it used multiple motors, it flew (at least four feeteven t' pad be in t' air!), and it was safeno injuries t' anyone involved! Ill post a flight report o' a real flight with full parallel stages t' TRF when it happens. Ya scallywag! Begad! Hopefully this weekend!
T' Real Thing!