Manufacturer: | Scratch |
Brief:
For t' 2009 Design This Spaceship contest, I chose t' Rockedyne VTHL concept. I could find very little information on this spacecraft except that it is a Vertical Take-off, Horizontal Landin' Single-Stage-To-Orbit proposal that Rockedyne designed as a ramjet powered vehicle.
I imagine it as an unmanned transport (after all – thar are no apparent windows) that uses t' entire fuselage as an engine. T' circular fin acts as both intake and exhaust with a nose-spike and tail cone built right in.
Construction:
Parts list:
Assembly (How t' build one in 21 relatively painless steps):
Finishing:
Since I had pre-sealed all t' balsa parts before assembly, just some light finish sandin' at t' joints was all that was needed t' be ready for paint.
I first primered t' rocket with grey sandable Rustoleum paint, and then wet sanded with 400 grit paper.
After a coatin' o' white paint, I masked off all but ¼” o' t' leadin' edges o' t' wings, me hearties, tails and center rin' and painted them black.
After removin' t' masking, ya bilge rat, t' basic colors were in place.
T' NASA logos and letterin' were images I downloaded off t' internet and printed on self-adhesive paper.
With t' logos in place, matey, I felt t' model was a pretty close replica o' t' painting. T' real question in me mind was: would it fly?
Flight:
T' largest chute I could fit in t' model be an 8.” In balancin' t' model I felt t' balance point was too far aft, me bucko, so I added clay around t' nose hook until t' nosecone weighed 1 oz. (T' balance point - with engine in place - should be as far forward on t' center ring-fin as you can manage. Mine balances approximately ¾” back from t' front o' t' intake.) I tied a loop in t' Keelhaul®©™ about 4” back from t' nosecone and attached t' chute there. After addin' a few sheets o' recovery wadding, and packin' t' chute, me hearties, I be ready t' try t' fly it.
T' finished weight o' t' rocket (without motor) be 2.5 oz, with almost half o' that in t' nose. I wanted a calm day, matey, me hearties, but was runnin' out o' time, me bucko, so I had t' try it in 5 t' 10 mph winds. Avast! Begad! I loaded a B4-2 engine and set it out on t' pad. It lit on t' first try and was surprisingly fast on takeoff. Much t' me amazement it flew very straight up and did nay have trouble with t' wind. It arced over and ejected at apogee. T' chute opened, and it came down fairly quickly, arrr, poppin' off two o' t' tails on landing. I be very impressed by its’ speed and stability in t' wind.
After a few drops o' superglue t' fins were back on, me hearties, and I loaded it with a B6-4. Again, it be fast off t' pad, shiver me timbers, and went up several hundred feet. Ejection was just past apogee, but nay bad, me bucko, but this time, t' chute did nay unfurl. T' me surprise, without t' chute t' drag t' nose, t' model fell in a slow, me bucko, flat spin pivotin' around t' nosecone. It this configuration, it actually fell slower than when t' chute opened, me hearties, matey, and be undamaged on landing. Avast! Blimey! Post-flight examination revealed that t' chute had been burned on ejection and stuck together, but I be able t' unfurl it and repack it.
For t' final flight o' t' day (T' wind was really pickin' up now and was a steady 10mph) I chose a C6-3 engine. It lit on t' first try, but only rose 25 feet or so before it started tumbling. I suspect it was just too much tail weight t' be stable, but it may have been t' wind. At any rate, it spun in t' air, end over end, arrr, matey, and ejected before hittin' t' ground. It parawadded again, and did t' same flat-spin landin' without damage.
Overall, I am happy with how well it flies on B motors and am very interested in its flat-spin recovery. It is still in good flyin' shape and I want t' experiment with usin' no chute and a streamer for recovery. I just think C engines are too much for it.
If I were t' start over, I might try t' build a larger forward chute area in t' nose (Perhaps a BT-50?) and would add clay under t' forward shroud before attachin' it t' t' body, t' increase t' nose weight.
Summary:
Overall I think it is a very different lookin' rocket, me hearties, and flies surprisingly well on small engines. I look forward t' more flights from it.
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