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Antares JS

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I have to question the 2-3 km/s on the Big Babylon at the bottom and the range of full earth orbit... 2-3 km/s is less than half the speed needed for that.
 

kuririn

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I have to question the 2-3 km/s on the Big Babylon at the bottom and the range of full earth orbit... 2-3 km/s is less than half the speed needed for that.
The projectile, I believe would have acted like a second stage with its own propulsion system.
The blast would accelerate the round and clear most of the drag of the atmosphere.
This is where most of the fuel consumption (and weight) occurs in traditional rockets.
Would have loved to see this come to pass. But not by Saddam Hussein, of course.
The article says it would have registered as a seismic event.
If you think you've seen smoke and fire (and noise) at a HPR launch................
Heh.
 

Neutron95

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Who needs an airframe when you can use the casing as the airframe ;)
That's exactly what the space shot I'm aware is is doing. It's getting to be a pretty standard practice for high performance flights, especially with larger motors. I just didn't want to get too into the details with my first post.
 

John_lennon

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To get up to 100 km, the change in potential energy is:
PE = mgh = 1kg * 9.8 m/s^2 * 100,000m = 1x10^6 N-m
To accelerate to 8 km/s, the change in kinetic energy is:
KE = 1/2 mv^2 = 0.5 * 1kg * (8000 m/s)^2 = 32x10^6 N-m
So, it takes 32 times the energy to reach orbital velocity as it does to reach orbital altitude on earth, ignoring the weight of your motors/propellant and aerodynamics. Total energy would then be 33x10^6 N-m.

By way of comparison, a Toyota Camry has a mass of about 1500 kg. The energy to get your 1kg payload to 100 km is about the same as the energy necessary to accelerate that Camry to 130 km/hr., ignoring, well, you know.
This is the beginners section. I just had to double check because this math is looking insanely hard to me. Thank God we've got some progressive thinking minds around. I know who to ask help with calculations. Can I ask what an OP is? Sorry I'm all very new to this. Thank God I'm going to try and keep it simple with some low powered, low fliers. Some of you guys sound like you should be teaching Physics, or Chemistry, or Engineering. This has been a great read. Thanks for theorizing what it would possibly take to entertain this idea even. I should learn a bunch from you guys. Do you recommend I download 1 of the Rocket Simulation software's is there anything Android based or IOS based. I've got an older touchscreen laptop that I think needs a tech to look at it. I think it's got some type of pirate admin software in it. The mouse starts doing all kinds of stuff like it's got a 3rd party moving it around. Luckily I haven't done much with it since I got it from the old women's estate sale I purchased it from. Truthfully I don't even know if it'd be worth getting it looked at. Sorry I got a little off topic there.
 

Joshua F Thomas

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. I just had to double check because this math is looking insanely hard to me.
This is secondary-school (high school for the US) physics. If you're going to do any amount of rocket building/design beyond "put my kit together according to instructions" then you'll need to start brushing up on that level of physics.
 

John_lennon

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This is secondary-school (high school for the US) physics. If you're going to do any amount of rocket building/design beyond "put my kit together according to instructions" then you'll need to start brushing up on that level of physics.
Luckily at the moment I'm a total beginner newbie. I'm trying to get a hobby to do with my grandson and remembered building a couple Estes kits at summer camp. It was fun, he's always drawing up plans for things he'd like to build. So it sounded like a good project for us to do together. Are there any books you can recommend reading to get me started in understanding more of what's going on?
 

Joshua F Thomas

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Luckily at the moment I'm a total beginner newbie. I'm trying to get a hobby to do with my grandson and remembered building a couple Estes kits at summer camp. It was fun, he's always drawing up plans for things he'd like to build. So it sounded like a good project for us to do together. Are there any books you can recommend reading to get me started in understanding more of what's going on?
The Handbook of Model Rocketry is considered the definitive source for most of what you need to do.
 

ewomack

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The Handbook mentioned above is a great book written by one of the inventors of model rocketry, but even its most recent 7th edition badly needs an update. It also contains a lot of information that no longer applies to modern model rocketry (the chapter on determining altitude, for example) and a number of its chapters contain very technical material that might be off-putting to absolute beginners (for example, the glider chapter). It might be a bit too much for someone who just wants to build and fly some rockets. In short, you do not need to read that entire 300-page book to build and fly model rockets. I'm not trying to commit model rocketry heresy here, but I don't think the Handbook is the best resource for absolute beginners. If you want to get more technical and detailed with model rocketry, it's worth reading, but even then the book really really needs an update.

To get started quicker and at more of a beginner's level, I would recommend looking for introductory videos on the Internet, possibly from Apogee Rockets or websites that go over only the basics that you will need to get started. Since you've built and flown rockets before, I don't think that you'll need too much information to get going again.
 

jrap330

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Beginners stick with Estes kits,Custom kits, just low power Model Rockets, and slowly go up in engine power A, B, C and D and complex builds. Read everything on Estes web page, their catalog, Apogee site and of course anything online. At moment you do not need to get aquatinted with sim sw. Kits first. Learn by building and flying, otherwise you will feel overwhelm.
 

Michael L

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Beginners stick with Estes kits,Custom kits, just low power Model Rockets, and slowly go up in engine power A, B, C and D and complex builds. Read everything on Estes web page, their catalog, Apogee site and of course anything online. At moment you do not need to get aquatinted with sim sw. Kits first. Learn by building and flying, otherwise you will feel overwhelm.
Define slowly :D
 

John_lennon

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The Handbook mentioned above is a great book written by one of the inventors of model rocketry, but even its most recent 7th edition badly needs an update. It also contains a lot of information that no longer applies to modern model rocketry (the chapter on determining altitude, for example) and a number of its chapters contain very technical material that might be off-putting to absolute beginners (for example, the glider chapter). It might be a bit too much for someone who just wants to build and fly some rockets. In short, you do not need to read that entire 300-page book to build and fly model rockets. I'm not trying to commit model rocketry heresy here, but I don't think the Handbook is the best resource for absolute beginners. If you want to get more technical and detailed with model rocketry, it's worth reading, but even then the book really really needs an update.

To get started quicker and at more of a beginner's level, I would recommend looking for introductory videos on the Internet, possibly from Apogee Rockets or websites that go over only the basics that you will need to get started. Since you've built and flown rockets before, I don't think that you'll need too much information to get going again.
Thanks for the info on the book. I do watch Apogee's videos on YouTube and I've looked through some of the information on their site. I'll definitely read some more this week and hopefully get to building if my schedule and grandsons schedules are both free over the next few weeks. I've already reached out to the local club in my state who said they'd be happy to have us come for a shoot. He even said that if we didn't have our rockets ready that they'd be able to find some for us to fly so we could experience some of the activities involved with the pre flight, launch, flight, and retrieval aspects at the launch site.
 

jrap330

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Define slowly :D
I will gladly define it....build kits first , start with model rockets, and flying low power models before designing model rockets and if you choose, than consider mid power or high power.
 

Michael L

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I will gladly define it....build kits first , start with model rockets, and flying low power models before designing model rockets and if you choose, than consider mid power or high power.
I bought tubes, 3D printed the nose cone and fin can, launched those with my grandkids. About the same time I bought a LOC Graduator (midpower), built it, bought a LOC 4 (high power) built it, successfully flew the LOC 4 for my L1 cert 5/1/21. BUT I'm almost 1/2 way through my second year in the club and the first flight at a club event was the L1 cert. In other words, about 18 months elapsed between start to L1 cert, After seeing my first HP launch my level of caution increased dramatically.

I've got a lot of time spent on modeling, well... learning to model... that's a work in progress. If I had built the LOC 4 per design I probably could have flown in on a minimal motor last year and got my L1 then. It's hard to say for sure though. That wasn't the path I wanted to take. It sounds odd but I wanted to learn from the process not just build a LOC kit and go. It turned out that it wasn't that easy.

When I started the process of getting an L1 cert I found out that it's not just light the fire and wait for it to come back. I even aborted the first attempt. I didn't take a rocket on launch day because the sim and actual rocket didn't match. A month later all of that was resolved and I launched, successfully. Kudos to the club members for their advice and counsel.

I complicated the L1 cert by building the rockets for dual deploy but not implementing dual deploy. Av bays take up space and they add weight. They change things. So much so that the Cg was too close to Cp for my comfort. There wasn't a comfortable amount of room for the chute, and changes had to be made. I love problem solving. I had already committed to an I350 motor and I really wanted a tracker onboard. I figured out a way to put one in the payload bay (working on a more permanent solution). Rockets is not a typo. When I changed the LOC IV I changed the LOC Graduator.

Somewhere between now and L2 attempt I would like to fly both rockets dual deploy (not for L2). Assuming that they survive that the curious side of me wonders if I could make them 2-stage rockets. LOC 44? :D I've been studying the modeling software and will eventually attempt a 2 stage model.

I think I know what I want to fly for the L2 attempt. I'm planning to scratch build whatever I fly. It'll be a while.

TLDR - have fun. Don't rush. 3/4 of the fun is learning about rockets. and rocket design... 1/8 is watching other rockets fly. 1/8 is watching yours fly and recovering it.
 
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BDB

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^^^^ I really like your 3/4 - 1/8 - 1/8 rule. It's true for me too.
 
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