General Rocketry Discussion!

[rwm]

I'm planning on attending LDRS this year on the flats. If you stop by, we can talk rockets and machining.

Biggest motor I've flown is "just" an M900.

It's possible! I will keep you advised. I'm sure it's a great event.
Robert

 

[ttabbal]

I've never even heard of that one! So far my biggest motor flown is an Estes C6!

Just how big is an M900? Sounds impressive!

3" diameter, about 30" long.



The rocket is 6" diameter, about 10 feet tall.

That's a smallish project for the big event. Estes and other hobby rockets are also welcome though.

 

[rwm]

I can hear that from here!

 

[Weldo]

That's a whole 'nother level! Amazing picture!

What are the legalities of building/launching something like that? I know you can get high power certified in three different levels. Something like that is almost beyond hobby and into full on engineering territory. Really cool stuff!

 

[rwm]

Here's a good one. Might want to fast forward some parts.

Robert

 

[Weldo]

That is a really cool video! I wasn't expecting it to spin so much. I guess this rocket was a spin stabilized type?

It's also interesting how quickly it stopped spinning when the stabilizing weights deployed. I'd like a better view of what that looked like!

I think my favorite part was the unceremonious clang as it landed back on earth.

Really cool stuff! Thanks for posting!

 

[ttabbal]

That's a whole 'nother level! Amazing picture!

What are the legalities of building/launching something like that? I know you can get high power certified in three different levels. Something like that is almost beyond hobby and into full on engineering territory. Really cool stuff!

You need FAA waivers in the US to fly stuff that big. Realistically, you need to launch with a club that sets them up. It's possible to get them yourself, but they can be a bit difficult to get set up. The certification is pretty easy, Level 1 is to build, fly, and safely recover using an H or I impulse motor. 2 is a simple written test for safety code things like how far away from people you need to be for various size motors and a flight with J/K/L impulse. 3 is M or greater impulse flight. For 3 you work with a mentor to document the build and they help ensure you are doing it safely. There are also requirements like redundant systems for parachute deployment.

The whole certification process is really just to help keep everyone safe. Even Estes model rockets can be dangerous if the parachute doesn't deploy. There is a picture of one that penetrated an enclosed trailer. The photo I posted is small for a level 3 project, but weighs in at about 50 pounds loaded with propellant. If it came in ballistic, which has happened to people, it would be very dangerous. And there is always the possibility of the motor malfunctioning.

If you want to look into doing it, the best option is to find a club launch near you. The groups are generally welcoming to new people and happy to help you get started. They also already have all the equipment for high power launches, which can get expensive fast.

Here's a pic of the electronics bay for the rocket above. Dual altimeters for deployment and a GPS tracking transmitter. The boxes are covers for holding batteries in place. I designed and 3D printed the plastic parts.

 

[Weldo]

That's pretty awesome! There are a few clubs around my area, if I progress further in the hobby I may look into joining one.

I love how the hobby can grow with you. You start out like me with Estes kits and simple stuff but eventually you can be doing full on rocket science. That project you're working on is really cool!

I wonder if ultimately your choice of how far you take the hobby is limited by your available launch site. I'm not sure you could find adequate space for a high power launch such as yours anywhere on the east coast.

 

[Nogoingback]

The whole certification process is really just to help keep everyone safe. Even Estes model rockets can be dangerous if the parachute doesn't deploy. There is a picture of one that penetrated an enclosed trailer. The photo I posted is small for a level 3 project, but weighs in at about 50 pounds loaded with propellant. If it came in ballistic, which has happened to people, it would be very dangerous. And there is always the possibility of the motor malfunctioning.

That reminds me of a friend who was messing around with a little hobby rocket one time in his yard. (He lives out
of town, on acerage.). He launched the rocket, to watch it come back down and punch a hole right through the roof of his motor home. I think he gave up on rockets after that...

 

[Weldo]

Part of the NAR safety code says that rockets should only be made of lightweight materials like balsa wood and paper, but I suppose at freefall from several hundred feet, even a plastic and balsa rocket has some decent momentum.