How do you build & fly a supersonic model rocket? 

Yes i 3d print the fins and nose cone, but on the HPR rocket level 3d printing the retainer is not the best idea since it is just plastic which can melt. For the fin designs, OpenRocket, a rocket design software can export your fin design as a obj file i think, and then you can put it into your 3d printer slicer software. When i built this rocket the feature had not came out so i printed out the fin design on a piece of paper and got the measurements from it and designed it in Onshape, i don't recommend doing it that way tough because that was very hard and i still didn't get it right, i recommend using OpenRocket and exporting them. Its a really good feature and OpenRocket is free. For the motor retainer you can get them from a online store called eRockets, there is quite a few choices, some cheap, and some a little more, but i recommend getting a more high end one, its better to get a good one than have your motor fall out of your rocket in flight. eRockets also has literally everything you could possibly need for building rockets. I highly recommend printing parts, its cheap and they work, you just have to understand the limitations, like not putting it by heat or under a lot of stress.

I used a hobby motor made by AeroTech, all AeroTech motors us APCP, which is solid fuel (ammonium perchlorate composite propellant). This motor was a H550 with the Super Thunder blend of the APCP.

Cardboard tubes made for rocketry from www.erockets.biz/

Hi, I’m MRD Aerospace on a alt account, it was just data logging altitude and acceleration.

@@MRDAerospaceTWO that make sense thank you MRD.

All AeroTech motors us APCP (ammonium perchlorate composite propellant). This motor was a H550 with the Super Thunder blend of the APCP.

@@ModelRocketDev it's ammonium perchlorate composite propellant

Ops, my bad.

Its quite complicated at this level of rocketry, start small with kits and learn the basics and get experience, then start to scale it up, the bigger you get the more expensive it gets, the motor i used in this rocket costed about $63, the rocket without the electronics probably costed about $100, then the electronics are about $200, so thats $363. You also need HPR certification. So start small, get experience, then start to scale it up.

An H550 hits really hard really quick, and then it didn't coast because my fins were thick. After the flight i took how long it took to get to apogee and how long it takes to travel 1 foot going mach one, not sure if i explained that right, but it did go mach one. That motor probably burned out not even at 200 ft.

I said everything there was to be said in the video.

@@ModelRocketDev including weight, thrust, TWR ???

I didn't mention that, but unfortunately the rocket crashed in a later flight so i don't know either of those and i never wrote them down.

@@ModelRocketDev ok, thanks

Im 90% sure it went supersonic, both of my simulations with 2 different apps agreed, OpenRocket and Thrustcurve . And 3k feet should be normal because the H550 burns for 1/2 a second so 90% of the flight is just coasting.

@@ModelRocketDev Oh I am quite familiar with the H550 DMS and RMS version and have flown many of them. Usually though, most supersonic flights go significantly higher than 3k. I guess that might be a result of your fins being rather thick slowing your rocket down after burn out. Regardless that looked like a super fun flight.

Nope, model rockets don't make sonic booms when they go supersonic, iv seen several go supersonic and none have had sonic booms.

Online explanations of Sonic boom are very bad

Supersonic speed is the speed of an object that exceeds the speed of sound (Mach 1).

We have electronics on board in our E-bays that are amazingly accurate that tell us the speed and altitude. It is very easy to hit mach 1 with a amateur rocket. Whats hard it making one that will hold up to the speeds.

That would be me, you can find my email in the channel description.