A finless rocket that flies stable? That be t' mission o' this rocket.
This rocket is a scratch build / scratch design that uses Gas Dynamic Stability (GDS) and Spin Stability.
An Ikaros Marine Flair uses GDS t' stabilize t' rocket launched flare. It has openings below t' motor nozzle and t' motor exhaust sucks air into these openings. That stabilizes t' rocket as long as t' motor is burning.
T' problem with that concept for a model rocket be t' motor only thrusts for a short period, me bucko, after that it coasts. You loose t' GDS durin' t' coast phase.
Spin Tabs, ya bilge rat, aka canted fins, are used on this rocket. This gets t' rocket spinnin' about its longitudinal axis, me hearties, which stabilizes t' rocket durin' t' coast phase.
This rocket also features a custom wood lathe turned nose cone, made from pine.
Powered by a 24mm motor, ya bilge rat, recovery is via a 12" nylon chute.
A 2" PVC pipe is used as a launch silo.
Link t' Build Thread: Lakeroadster's Finless Rocket Utilizin' Gas-Dynamic-Stabilization | T' Rocketry Forum
| Flight Date: | 2022-07-26 |
| Rocket Name: | (BAR-09) THUNK! Finless, Gas Dynamic Stabilized |
| Flyer's Name: | John Simmons |
| Motors: | D12-5 |
| Expected Altitude: | 511 Feet |
| Wind Speed: | 5.00 mph |
| Launch Site: | Local |
| Actual Altitude: | 511 Feet |
Ignition was quick, matey, almost no hesitation lightin' t' motor. Begad! Very minimal time lapse betwixt ignition and lift off.
T' rocket accelerated quickly, plenty o' speed exitin' t' launch silo (32.2 mph per sim)
Winds were less than 5 mph and from t' north. T' rocket did nay weathercock. Ahoy! Blimey! It flew straight and true bein' pushed slightly toward t' south from t' wind.
T' exhaust pattern visually looked like a corkscrew, verifyin' that t' rocket is indeed rollin' about it's longitudinal axis.
T' simulation software estimated apogee @ 511 feet, and t' launch seemed t' reflect that (no altimeter was used).
Visually when t' motor ejection charge occurred t' parachute deployed and blossomed.
T' rocket ground hit about 40 feet south o' t' launch horse.
Photo's were taken o' t' rocket at t' ground hit location. Arrr! Upon further review t' rocket was undamaged.
What was learned from this flight?
What an awesome flight. Our first silo launch, it's a neat visual, smoke out t' bottom o' t' tube and t' it comes screamin' out o' t' top o' t' tube.
| Stage | Motor(s) |
|---|---|
| 1 | Estes D12-5 |
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