• Elijah Sohn
  • Amateur Rocketry
  • Photography
  • Electronics
  • Composites
  • More
    • Elijah Sohn
    • Amateur Rocketry
    • Photography
    • Electronics
    • Composites
  • Elijah Sohn
  • Amateur Rocketry
  • Photography
  • Electronics
  • Composites

Blackout - Zero to Mach 2.4 in 1.1 seconds

Project Overview:

  • Diameter: 2.2" / 54mm


  • Length: 43"


  • Propulsion: EX K2300 SRM


  • Apogee: 16,632ft AGL


  • Max Speed: Mach 2.4/2700fps


  • Peak Acceleration: 100G


  • Recovery: Successful


  • Launch date: 3/1/2025


Project Requirements

  • The Rocket shall utilize a re-loadable 2.125" diameter solid rocket motor (the Motor)
  • The Rocket shall contain a two stage recovery system to facilitate <35ft/s ground hit velocity
  • The Rocket shall be composed of as few parts as reasonably possible
  • The Rocket shall contain an onboard camera
  • The Rocket shall be stabilized by a static fin assembly
  • The Motor shall be static tested before flight.

System Architecture

Blackout is a "flying case" rocket, meaning that the air frame or body tube is omitted and the aluminum motor casing makes up a significant portion of the outer surface of the rocket. This design reduces weight and simplify construction. The rocket motor takes up the bottom 24" of the motor casing, leaving 3" of tube at the forward end for the nosecone assembly to slide into. The CFRP fin can assembly then slides over the motor casing and is retained by a thrust ring on the aft end.

Propulsion - 


Blackout was a breakthrough vehicle for 54mm experimental motors.  Combining a HAM radio tower tube with an electrical insulating tube from McMaster, a full motor casing + liner assembly can be acquired for <$100, less than a fourth the price of commerical options.


Blackout's specific motor is designated a K2300. It was powered by 2.75lbs of APCP propellant, cast by the amazing Alexand

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Composites -


The only composites of note on Blackout were the fin can and nosecone. The fin can was made from a 6" long carbon fiber tube with four fins bonded to it. The fins themselves are commerical carbon fiber plate, cut out and beveled on a cnc router. The leading edges of the fins are protected by bent stainless steel caps.


The nosecone assembly for this project was reused from Hangover.

Launch

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Elijah Sohn