MIN DIAMETER ROCKET - NESSY - CTI M2245
HTML-код
- Опубликовано: 20 авг 2024
- Build and flight of my scratch built 75mm minimum diameter rocket, named Nessy. Sims expected a max altitude of 43K at a top speed of Mach 3. The rocket was designed around CTI's M-2245 Imax motor.
At Max Q, Nessy hit Mach 3 and its nosecone sheared. After looking at the onboard video and talking to some fellow rocketeers, we think Nessy's non-zero angle of attack caused the dynamic pressure to apply a shear load to the nosecone, rather than a compression load when the angle of attack is near zero. All that was recovered was the nosecone, as it's where the Featherweight Tracker was located.
An optimized version of Nessy, Nessy II, is planned to fly at BALLS 2022. It will fly the same CTI M-2245 motor.
Flight Computer: Featherweight Raven4
Tracker: Featherweight Tracker
Camera: RunCam Split 3 Nano
Launch Site: Aguila, AZ - Tripoli Phoenix
Music: Gedanken by Isolated
Very cool
May she Rest In Peace
Kinda late to the video, but what kind of resin/epoxy did you use for your fins with the carbon fiber? Also how did you get such a clean cut/edge where the carbon ends at the forward part of the fins?? They’re absolutely stunning. I’m planning on building a minimum diameter project as well so that’s why i’m asking…
I use West Systems (105 resin with 207 hardener). About 18 hours after the layup was applied, I’d take a razor blaze and run it down the edges until they’re are clean and smooth. If you wait too long, the layup will get too hard to cut with a blade, so you’ll have dremel it off. Goodluck with your project!
That is one beast of an engine. Good luck on the second try. Any thoughts on how you are going to address the angle of attack?
Thanks! I’m thinking of reinforcing the nosecone with Kevlar fabric so it has more shear strength while keeping the nosecone radio transparent for tracking. Ill also go with a higher stability margin to reduce the chance of any yaw-pitch coning that can cause a shear load on the nosecone. Also fly earlier in the day, winds tend to pick up in the afternoon, which is when I flew Nessy. I think that should be enough to withstand the violent motor. If Nessy could’ve endured 0.4 seconds more, it would’ve survived.
Are you flying Speed Demon again?
Probably not anytime soon. I’d have to buy the AT 5G case which only fits Speed Demon. I have a two stage and Nessy II in queue so Speed Demon might fly in a year or so.
@@alexmoreno2519 cool
May she Rest In Peace