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Joshua F Thomas

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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.
Treating this as an impulse problem, we can consider it as a change in momentum (which is the definition of impulse). At least one source I checked considered 9.4 km/s (9400 m/s) as the delta-v needed to get to and sustain LEO.

Assuming 1 kg mass, J = p2 - p1 = m(v2 - v1) = 1 kg (9.4 km/s - 0) = 9.4 * 10^3 N-s

So one would need 9400 Ns. That's an M-class motor, but it also assumes your entire rocket plus motor is only 1 kg! The problem with having to haul your motor mass around quickly becomes apparent.
 

Voyager1

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He may not be a flat earther, but it was fun to speculate.
Indeed it is! Totally agree! I’ve often thought about space launches myself, but I’ve generally accepted that a simulation is about the best I will ever achieve with that particular dream.
 

Woody's Workshop

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He probably will not come back.
I think he was looking for a different response than he received.
However, while he may have the knowledge to take on such an endeavor, his OP was way premature.
Very little thought has actually been put into cost, location, channels to go through to complete such a project.
It kinda sounded like to me he had worked it all out on paper (computer) and thought he could run down to the hobby shop and hardware store and do the launch the next day from his back yard at Mom n Dad's place.
Because something like that would be picked up by NORAD and investigations would pursue...
 

Richard Dierking

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This will not be the last time this subject will be posted. It might just be a space shot and not orbital. Perhaps the reason we don't see it as much now is the separate School and University Discussions. Many university student teams want to do space shots, and I bet most of them don't even know why. If they really thought about it, they would probably choose a different goal.

Calling the OP an idiot is a bit rough in my opinion. And, if you thought this was a stupid or useless subject you don't really have to watch or participate. Pointing out mistakes or deficiencies is one thing, even if it's blunt, but I don't think we should insult anyone.

I think it's actually good to have these conversations. And, again, you can watch and participate or not. I think many people have aspirations for high-altitude flights. But, after you have been in the hobby and gain some experience you understand the difficulty and expense. I would be happy reaching 50K'!
For the orbital subject, it also helps to have some knowledge about the history of international spaceflight and first attempts to orbit a satellite. I think Sputnik and Explorer would have come much later if the ICBM/Nuclear Arms race didn't happen first.
Hum, that might be the next space shot post, "I would like to make an ICBM, which epoxy should I use?"
 

blackjack2564

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U r probably right, I was a bit harsh. But the fact remains he spent "just a couple hours" doing research.

U would have to have access, or buy, over 1 million in equip. just to manufacture such a project and IF u had motor making skills and could make your own propellent the raw cost of the rocket would be upwards of 300k plus pad...hauler..and 7-10k a day launch fees. To even think 1000 pounds sterling could fund such a project...well there ya go...lol
 

Richard Dierking

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Yes, I do see your point. Discussing it or even dreaming about it can be interesting. But, it's kind of academic. I don't think anything like an orbital project could be done on a budget. Particularly one so limited. One would need a lot of money, Like SpaceX when it started, and even Musk almost ran out of funds.

And, the math is interesting, like what Joshua posted.

When I'm able to obtain the Rocksim Professional edition, I'm looking forward on running some sims on sub-orbital trajectories. Entering the motor data is going to be a challenge.
 

XrayLizard

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U r probably right, I was a bit harsh. But the fact remains he spent "just a couple hours" doing research.
Hehehehe reminds me ...
of Oh my! The support tickets we received at ST Micro, from University students.... LOL. "we would like 100 free parts. We also want the code. And the hardware design.
We will mention you on our facebook page!!!
LOL!

And with self given titles that were really a hoot.

Thankfully I am sure it is a small percentage.

P.S. We told them NO. or.. Yeah, Nah.
 

BDB

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Just saw this and it reminded me of this thread.

96AD7BD7-83F2-4FE1-A94F-D6128E0843CF.png
 

rklapp

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I don't know Bobby Potter but wonder if this thread influenced his writing.
 

rklapp

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There's this...

1604443345044.png


 

mikec

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From that website: "We’ve done all the foundational work," said Rudy. "Now it’s just about scaling up." Yeah, right.
 

Apogee Components

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I don't know Bobby Potter but wonder if this thread influenced his writing.
It did. This community often does. If you ever have any good ideas that you think should be talked about, feel free to send them my way. I'm always hungry for topics.
 

rklapp

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It did. This community often does. If you ever have any good ideas that you think should be talked about, feel free to send them my way. I'm always hungry for topics.
How about possible financial woes for NAR or Tripoli amidst the pandemic?

 

Apogee Components

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I don't know if the content is there for a full Peak-of-Flight article, but I am writing a blog post for it. To move it to the Peak-of-Flight, I need to find hard data to support the claim they are actually under financial hardship, otherwise it is just opinion (which is why it is landing in the blog). My goal is to show what you can do, on top of your annual membership dues, to benefit NAR and Tripoli.

That all being said, I have not yet read the article for the electronic rocketeer. As my research continues, my opinion on this all could change.

If you can point me to better data, I'm happy to take up the cause.

P.S. I changed my Amazon smile to NAR. What a brilliant suggestion.

Edit: Removed proprietary data I probably shouldn't have included.
Edit 2: Included the goal of my piece
 
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Richard Dierking

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I should post, Old Timer with Little Dreams.
I'm looking forward to the Rocksim Prof edition so I can run some sims.

I believe that groups will continue to pursue space shots but probably mostly university teams.
It seems after GoFast that conversations around the campfire shifted almost immediately to amateur orbital flights. Maybe that seemed like the logical new chapter for amateur rocketry. For me, I think the next logical step would be a space shot with a downrange trajectory. How far downrange would be an excellent question, but I think over ocean would be necessary. So, this would be a single shot or at least a very difficult recovery and still result in the destruction of the rocket because of the sea water.
Anyway, flight over the Atlantic is something I'm going to continue to work on. Don't know how much I will accomplish but it's a fun project to dream about.
 

Neutron95

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I'm also aware of one or two amateur projects aiming for a space shot with commercial motors. In theory, a highly optimized N5800 to M2245 flight could scrape past the Karman Line, but two stage rockets are hard, and it remains to be seen whether an amateur can actually make an airframe that's both light enough to hit that kind of altitude and strong enough to survive the flight stresses.
 

Apogee Components

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I saw some pretty impressive nomex-honeycomb / carbon fiber airframes from Portland State Aerospace Society (who are looking to do a liquid fueled spaceshot). According to their data it had a 5x strength-to-weight on its purely carbon fiber counterpart.

I also saw on John Coker's personal website, a how-to guide for a similar honeycomb sandwich structure (though still with paper tubes). Might be a good place to start airframe research, as all of Portland State's work is Open-Source and John Coker makes his knowledge free to the public. Maybe good resources to point those teams toward.
 

jimzcatz

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give it up, can't be done. Especially as you say as a beginner. you cant launch into orbit without ground control and real time tracking.
 

rklapp

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give it up, can't be done. Especially as you say as a beginner. you cant launch into orbit without ground control and real time tracking.
I don’t think we’ve heard from the OP since the beginning of this thread.
 

Zertyme

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I'm also aware of one or two amateur projects aiming for a space shot with commercial motors. In theory, a highly optimized N5800 to M2245 flight could scrape past the Karman Line, but two stage rockets are hard, and it remains to be seen whether an amateur can actually make an airframe that's both light enough to hit that kind of altitude and strong enough to survive the flight stresses.
Who needs an airframe when you can use the casing as the airframe ;)
 

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