Kerbal Space Program Unofficial Model Rocketry Megathread

[TeslaPenguin1]

2 hours ago, RealKerbal3x said:

Also, I don’t even know if the laws here would allow the building of rocket engines.

Just get the Estes ones! (if you can order them)


Anyway, just realizing that I forgot to post about the launch on Dec. 8. It was awesome, I only lost 1 thing. It was a payload: A penguin with a santa hat. One of my rockets got destroyed. It's now retired after repairs. All in all, it was fun. Pictures later, I'm feeling lazy right now.

[Ultimate Steve]

Today, after many delays, we have launched 3 more rockets with the goal of using trigonometry to find their altitudes.

Things that went wrong: I can't find an SD card for the third camera, which also contains video of past launches on it. Grr. It's hopefully somewhere. I broke the giant tape measure. I broke the camera tripod. I broke a makeshift launch lug and split a rocket in half (along a poorly manufactured joint line, but still).

But some things went right!

Launch 1 - Tiny A-103T engine on my sister's Spaceloft model rocket, about a foot tall, really small. We lost it. Nobody saw it after it shot off the pad. And because it was a cornfield it was really hard to distinguish the rocket from the corn, so RIP Spaceloft.

Launch 2 - Neutron on an A8-3. Success! Mostly. Parachute did not deploy because it had been packed for a week or two. Rose 23.5 degrees above my position, which was 2 degrees below the launch site, 200 feet away. Calculated altitude is around 80 feet, which is way lower than expected. It also almost hit my sister on the way down. This is the first time I have trusted my sister with the launch controller ever since she almost blew my head off about 2 years ago. Can't blow my head off if I'm 200 feet away!

Launch 3 - Paradox on a B6-4. I'm 80% sure it was a B6-4 but I loaded these rockets a week ago but the weather, daylight, and schedules of friends did not comply until now. Rose 52.5 degrees above my position,  so about 253 feet if it went straight up, which it didn't. It came sort of towards me and to the right. I'm estimating a 20 degree launch angle, but it wasn't directly towards me, so ~15, that would put it closer to, perhaps below 200 feet. Also way lower than expected. The parachute on this one didn't deploy either.

 

But, man, watching the launches from 200 feet away instead of 30 was definitely a cool experience. It's much easier to see the rocket fly its full trajectory and is really eye opening. I highly recommend it if you have a friend/family member to conduct the launch.

[qzgy]

On 12/24/2018 at 3:40 PM, Ultimate Steve said:

Can't blow my head off if I'm 200 feet away!

If she is really intent on it and has her aim dialed in oh yes she can

[TeslaPenguin1]

On 12/26/2018 at 10:10 PM, qzgy said:

If she is really intent on it and has her aim dialed in oh yes she can

Not if she’s following the NAR safety code; you can’t aim rockets more than 30 degrees from the vertical, and you can’t launch at targets.

[qzgy]

2 minutes ago, TeslaPenguin1 said:

Not if she’s following the NAR safety code; you can’t aim rockets more than 30 degrees from the vertical, and you can’t launch at targets.

Well, of course if she's following a safety code, nobody would be hurt (generally). Its called a safety code, not an intent to kill.

[Ultimate Steve]

Big thing 1: My honors physics class did a model rocket unit. He's not doing it again next year, and he gave me the leftover engines... More than 30 A8-3 engines... That's quite a lot and I don't know what I'll do with that many low power engines... But a static fire is definitely on the list.

Thing 2, I launched 3 rockets yesterday, all of which were firsts or record setters.

1. Midget flight 1. I was given this rocket a long time ago, and it's like 3 inches tall, making it the smallest rocket I've ever flown. I flew it on a 1/2 A engine. Despite that it went really high, and we didn't find it until later on, looking for something else. A fin broke off on landing, but that's easily fixable, and somewhat expected when using tumble recovery.
2. X-3 Red Goblin flight 3. This rocket is one I built almost entirely by myself, from things lying around, except for the parachute. I don't like making parachutes and the ones you can buy are way better than the ones I can make. This rocket is a cluster rocket, with space for 2 engines. It flew on two A8-3s. It has done this in the past, on flights 1 and 2. However, neither flight had a successful ignition, only one engine ignited. Yesterday I wound the igniters together tightly, taped the launch controller clips on, and lifted the wire up on a tripod to give the rocket some slack if the engines didn't ignite at exactly the same time. And it worked! Both engines ignited, although slightly apart, as it launched probably 30 degrees to one side. The parachute didn't deploy, mostly due to shoddy design of the shock cord mount. That should be fixed in time for the next flight, whenever that will be. A fin broke on landing, but that is easily fixable.
3. X-4 Red Skywalker flight 2. This is another rocket I built by myself except for the parachute and some spare parts from other incomplete or broken rockets, and probably the most impressive flight of the day. It is a two staged rocket, one of only two in the fleet, and the other one is earmarked for a very important mission, most likely its last. That leaves me with a surplus of booster motors, so I built this rocket. This flight carried an altimeter, and I was standing 200 feet away with an angle measurement device in an attempt to check the altitude. In addition, this rocket had a payload bay, with a lego man, a piece of paper, and maybe a few other things inside. In this case, the rocket was powered by a C11-0 and a C6-5. The launch was spectacular, but the wind caught it despite its small, slightly melted parachute, and it blew half a cornfield over, making it the farthest I've ever had to walk to recover a rocket. We didn't find the first stage, but it's basically just a small cardboard tube and a washer, so easily replaceable. Final altitude was 838 feet according to the altimeter, but that was not backed up by the angle measurement, which was 55-65 degrees. However, I saw the rocket fly off to the west from my perspective, and the personnel at the launch site saw it go mostly north. Plus, I was distracted by how awesome of a view it was, and was trying not to lose the rocket, so that number is probably not super accurate.