[OFF TOPIC] JOwen's Rocketry Shenanigans

[JOwen]

Figured i'd start a thread so I don't clog up chat with the LARGE messages every time. I got permission from Calico to do this so hopefully this isn't against any rules.

for those who've managed to miss my rocket spiels:
I am part of a small amateur team developing a rocket to go to space. the karman line, the boundary to space, lies at 100km or ~328,000 ft above sea level. my rocket to go there is 14 feet tall, 8 inches in diameter, powered by one EX-R21600 rocket motor designed and developed in-house, and the rocket reaches a top speed of roughly mach 5.2.
this won't fly until spring 2028. but in the mean time, there will be lots of cool rocket stuff for the purpose of R&D.

I'll keep this thread updated for anyone who is interested. feel free to ask any questions you have about the rocket(s) and i'd be happy to explain.

- JOwen

[tbyunomi]

Wowzas whattttt

[JOwen]

TIMELINE 
this will be kept up to date.

Completed tasks as of 10/01/2024:

Spring 2023: "Vanishing Act" mission - High acceleration & structure test (mach 1.12 / 6,800 ft)

Fall 2023: "Risky Business" mission - extreme acceleration, aero heating, long range telemetry test (mach 2.38 / 13,100 ft)

Spring 2024: "EXJ 670" rocket - avionics and composites testing (mach 3.12 / 23,169ft)

Projected timeline as of 10/01/2024:

spring-summer 2025: "Super Risky Business" - staging, telemetry, tracking, etc test (mach 3.5 / 80,000 ft)

2025: unnamed mission -  hypersonics test (mach 5+ / 100,000+ ft)

2026 or 2027: Space shot! mach 5+ / 390,000+ ft (subject to design change)

[JOwen]

this was originally in the top post, but I felt like it shouldn't be. each milestone will get its own thread reply from now on.


on Sunday, may 28, at the san luis valley rocketeers launch site in alamosa, CO, I launched a small research rocket called "Vanishing Act" to test structure, avionics, and recovery systems under high acceleration. the 3.9lb (1.77kg) rocket produced 178lb (81kg) of thrust and accelerated from a standstill to mach 1.12 in about 1.5 seconds. the test was a complete success. next up is a test rocket to mach 2.15. this rocket will be ready to fly by the end of this summer but due to FAA altitude restrictions, I may not be able to fly it in utah in 2023. we'll see how it ends up working out. turns out its tricky to stay below 10,000 ft (about 3 km) above ground level  while going mach 2 vertically.

[JOwen]

"Risky Business" Rocket design - for the next major test flight.

simulation data:
Peak Velocity: 1,671 mph / 2,689 kph / mach 2.177
Apogee: 16,057 ft / 4,894 m / 3.04 mi
Peak Thrust: 356 lbs / 161.5 kg / 1,584 N

About 2/3 of the red tube section is taken up by the motor. Around 3/4 of the total weight is of propellant.

[Cool172]

is anything salvageable from these rockets when they come back down?

[JOwen]

is anything salvageable from these rockets when they come back down?

Yep. They are completely reusable! Refill the motor with propellant and you’re good to go. They deploy a parachute at apogee, which is held closed until a predetermined altitude on the way down, when the parachute opens. It’s then located with a built-in GPS tracker. All of this flight/recovery control is done autonomously by the on board avionics software, which also measures and reports the altitude and speed obtained during flight.

[JOwen]

Started work on "Not a Guided Missile".

this rocket is a silo-launched rocket with servo actuated fins and a set of canards (smaller fins at the top of the rocket). the canards are used to control roll so the rocket isn't constantly spinning. the fins are used to steer the rocket.
the rocket is launched from the silo using a short burn rocket motor mounted in a mount with a mechanism at the top that makes it so the motor locks in place, then when the thrust pushes it up, the lock partially disengages, so when the motor burns out the "silo booster" is ejected out the back with built-in springs. 

using the fins and canards, the rocket can control itself with or without thrust (assuming it has enough airspeed) and the trajectory is set using time only. Guided rockets are illegal because they could potentially be used as guided weapons, but actively stabilized rockets are fine. this rocket stabilizes itself given a hard-coded trajectory. 

for maximum speed tests, the rocket would take a hard turn right out of the silo so that at ~30-50 ft it could do horizontal powered flight. it may look like a cruise missile during these tests but there is no guidance, and the rocket is made of lightweight, biodegradable materials (mostly cardboard with some PLA which is biodegradable-ish). if it hits something, I am liable but the chances of that are low given where the tests will be held. even if it did hit something, being made of lightweight materials with a thin walled carboard tube it probably wouldn't cause any significant damage.



also for anyone curious about the propellant used in my rockets, the latest recipe is made of ammonium perchlorate, aluminum powder, hydroxyl terminated polybutadiene (HTPB), paraffin, iron oxide, and sometimes a little castor oil. I won't specify the exact ratios for obvious safety reasons but those are the chemicals.

[JOwen]

Motor choices have been made for the first high-altitude rocket.

this rocket will use commercial, off-the-shelf motors to keep things fairly simple. the main point of this rocket is to get experience sending things to the edge of space and, importantly, bringing them back. 

there will be single stage and two-stage variations of this rocket, the single stage one intended to go ~50,000' above ground level, and the two-stage version designed for 90-120,000' above ground level. both designs will likely break mach 3.

this rocket will be launched within two years or less.

in the mean time, a rocket named "Risky Business" will break mach 2 for the purposes of testing avionics and structures in extreme G-load environments, as well as getting a little experience at higher speeds than the current fastest any of my rockets have gone, which is mach 1.2. this rocket will fly in the black rock desert this september-october.

[JOwen]

Completed Space Shot rocket concept!


 this design is pretty fun. it weighs only 90 pounds, so it wont be the kind of thing to take payloads up in the future lol. But it's a great proof of concept and cheap(ish) to run development platform. It's a two stage rocket with about 80% of the space in each stage taken up by propellant, the rest being avionics and recovery gear. this rocket is completely re usable.
the launch of the space shot rocket has also been moved up!

though skinny and light, this rocket doesn't skimp on the power, flying to an altitude of 378,870 ft above ground level, with a peak speed of mach 5.06. though not really relevant in spaceflight, its fun to calculate that it has a peak horsepower of 17,580.

anyway that's today's ramble for you