Author Topic: Easiest path to 100km? (Read 11615 times)

ClaytonBirchenough · « **on:** 01/12/2014 03:50 pm »

On May 17, 2004, Civilian Space eXploration Team (CSXT) launched their "GoFast" rocket to space. Estimates in cost of the launch and associated attempts vary wildly, but all agree it was extremely expensive. No "amateur" has been to space since...

Launching rockets to space is not easy and not the least bit cheap. However, I (and others I hope) believe that it can be done cheaper than what it currently costs. I'd like to discuss the "easiest" and "cheapest" (cheapest development and single launch scenario) launch vehicle that can be built by an amateur to reach space.

In my opinion, these are the following design characteristics such a launch vehicle would have...

Re-usability: Not required. While it would be nice to reuse and recover the rocket for reuse, this is not a must. Reuse would only be considered for electronics and only considered for rocket motor and casing if it required minimal work to make flight ready again.

Propellant: Solid. Potassium Nitrate/Sucrose Propellant (KNSU). LOW performance (~130 sec ISP). VERY CHEAP. Easy production.

Staging: Not required. Adding stages adds complexity, electronics, and cost. A boosted dart is a concept that attracts my attention. Staging will be considered only if the performance gained > complexity and cost required for addition of stages.

Casing: Aluminum? Not really sure about the casing, but aluminum seems to be the best because it increases the mass fraction over alternate choices. Heating is also and issue and aluminum seems to be the best choice price and performance wise. In addition, are there any old, retired rocket casings for sale? Perhaps these can be bought and re-purposed to hold KNSU propellant while providing a high mass fraction.

Nozzle: Concrete? Many amateurs use concrete to make nozzles. It seems to work fine, and it's cheap!

Guidance: Fins! Passive, no need for anything crazy expensive!

Recovery: Not really my department, but it seems that a locator can be put on the rocket for very cheap. I am not recommending real-time telemetry. I think that GPS position can be logged by a flight computer and downloaded after recovery of the payload/electronic section.

Launch site: Ocean platform. It seems a launch conducted miles out at sea would require a lot less paperwork and would make it easier to get permission to launch.

***UNMANNED

It seems 1900 m/s delta-v is a good aiming point for a rocket aiming to reach space that is launched from sea-level. In addition, ROCKOON LAUNCH IS OUT OF THE QUESTION. I'd also like to stay away from non-rocket space launches and exotic propulsion.

Also, here are some links that may be useful in the discussion:

The Potassium Nitrate/Sucrose Propellant (KNSU) (Richard Nakka's Website)
KNSU Propellant Chemistry and Performance Characteristics (Richard Nakka's Website)
Most information on CSXT's "GoFast" Rocket
Qu8k rocket launched to over 100,000 feet

As all of this is just my opinion, I'd really like to hear your thoughts on how you think such a launch vehicle should be designed.

Vultur · « **Reply #1 on:** 01/12/2014 05:11 pm »

By cheapest, do you mean lowest TOTAL price or lowest price per launch?

If the latter, and if you're going to do a lot of launches, the cheapest way to get things to 100km might be a gun (eg Project HARP... I think that got ~180km). Assuming, of course, you can get civilian access to a gun that size...

ClaytonBirchenough · « **Reply #2 on:** 01/12/2014 05:32 pm »

Quote from: Vultur on 01/12/2014 05:11 pm

By cheapest, do you mean lowest TOTAL price or lowest price per launch?

If the latter, and if you're going to do a lot of launches, the cheapest way to get things to 100km might be a gun (eg Project HARP... I think that got ~180km). Assuming, of course, you can get civilian access to a gun that size...

Thanks for responding!

I'm looking for a lowest TOTAL price (development, launch, etc.). Also, I was looking for traditional rocket solutions to getting to 100 km.

I'll edit my original post to make things clearer.

Vultur · « **Reply #3 on:** 01/12/2014 07:30 pm »

Quote from: ClaytonBirchenough on 01/12/2014 05:32 pm

I'm looking for a lowest TOTAL price (development, launch, etc.).

Ah, OK then, guns are probably out of the question (EDIT: if you're only launching once or a small number of times).

Quote

Also, I was looking for traditional rocket solutions to getting to 100 km.

Why? More developed/well understood? Too much g forces on the payload with gun/mass driver/etc. type options?

Also, why are you excluding rockoons? More complexity?

ClaytonBirchenough · « **Reply #4 on:** 01/12/2014 07:43 pm »

Quote from: Vultur on 01/12/2014 07:30 pm

Why? More developed/well understood? Too much g forces on the payload with gun/mass driver/etc. type options?

Also, why are you excluding rockoons? More complexity?

I'm doubtful amateurs would be able to able to produce such a "gun/mass driver/etc.". All the launchers that fall into the "gun/mass driver/etc." seem to counterintuitive to the "cheaper" and "easier" philosophy. G forces would also be a factor as high g forces implied by a gun or mass driver launch would severely limit the kinds of payloads to be launched.

Rockoons are not a terrible idea. In fact, I love the idea of rockoons. Rockoons allow for...

- Less drag
- Better engine performance because of high altitude
- Little or no payload fairing

However, the logistics involved with a rockoon launch are a problem. 1. Electronics 2. Winds (Drift of rocket launching platform) 3. Permits

notsorandom · « **Reply #5 on:** 01/13/2014 07:50 pm »

Quote from: ClaytonBirchenough on 01/12/2014 03:50 pm

Propellant: Solid. Potassium Nitrate/Sucrose Propellant (KNSU). LOW performance (~130 sec ISP). VERY CHEAP. Easy production.

KNSU or more likely KN-Sorbitol is pretty cheap yes but there are some major draw backs as the sugar shot to space people have found out. Casting and using larger grains has turned out to present problems with cracking and structural failure when fired. These could be overcome in a number of ways but the extra time spend developing essentially a new motor technology will eat into the budget. The hydroscopic nature of the propellant also make producing and handling the motors a bit more difficult. Lastly the ISP is about half that of other mature commercially available solid propellants. This is going to have the effect of increasing the size and perhaps cost of the rocket. It could be that using a more off the shelf propulsion system ends up being cheaper and quicker depending on how the project is being financed.

ClaytonBirchenough · « **Reply #6 on:** 01/13/2014 11:30 pm »

Quote from: notsorandom on 01/13/2014 07:50 pm

KNSU or more likely KN-Sorbitol is pretty cheap yes but there are some major draw backs as the sugar shot to space people have found out. Casting and using larger grains has turned out to present problems with cracking and structural failure when fired. These could be overcome in a number of ways but the extra time spend developing essentially a new motor technology will eat into the budget. The hydroscopic nature of the propellant also make producing and handling the motors a bit more difficult. Lastly the ISP is about half that of other mature commercially available solid propellants. This is going to have the effect of increasing the size and perhaps cost of the rocket. It could be that using a more off the shelf propulsion system ends up being cheaper and quicker depending on how the project is being financed.

Thanks for taking your time to respond.

I think sucrose is a better fuel than sorbitol because of its wider availability. I know all of this is a very crude way constructing and flying a rocket but my idea with such a project was to formulate an idea on what characteristics the rocket should have and then test the crap out of it. That way, the project would be fun, entertaining, and interesting. Also, if you launch a rocket successfully, that's awesome! However, if it blows up spectacularly, that's also pretty freagin spectacular to watch.

With the hydroscopic nature of KNSU, I figured you could vacuum pack the grains and install them in the rocket shortly before launch.

Again, with the cracking and structural failure; test, test, test!

simonbp · « **Reply #7 on:** 01/14/2014 10:14 pm »

The cheapest way to 90,000 ft is a simple latex helium balloon. If you launch from there, 100 km is not so hard...

Oli · « **Reply #8 on:** 01/14/2014 10:55 pm »

My pick would be that Lox/Alcohol rocket from Copenhagen Suborbitals. They're amateurs, so I guess they've picked the cheapest option available to them.

ClaytonBirchenough · « **Reply #9 on:** 01/15/2014 12:57 am »

Quote from: Oli on 01/14/2014 10:55 pm

My pick would be that Lox/Alcohol rocket from Copenhagen Suborbitals. They're amateurs, so I guess they've picked the cheapest option available to them.

Ah. Maybe I wasn't clear...

This would be an UNMANNED attempt.

I'll correct my OP to make it more clear.

Rick Maschek · « **Reply #10 on:** 01/13/2018 09:54 am »

We now have successfully test fired two 12" KNSB (sorbitol) motors with 18 second burn times.
I have now made 12 sugar motors from 4" to 12" without CATOs and we are on our way to 100 Km.

Our last 12" static fire test last month:

Grain cracking is no longer a problem and moisture not an issue in the desert.
We are planning a staging test next week of already flown 6 and 3 inch rockets.
Space shot will be with reusable 2-stage 12 and 6 inch motors.

Rick

Rick Maschek · « **Reply #11 on:** 01/14/2018 05:23 am »

Quote from: ClaytonBirchenough on 01/12/2014 03:50 pm

On May 17, 2004, Civilian Space eXploration Team (CSXT) launched their "GoFast" rocket to space. Estimates in cost of the launch and associated attempts vary wildly, but all agree it was extremely expensive. No "amateur" has been to space since...

Launching rockets to space is not easy and not the least bit cheap. However, I (and others I hope) believe that it can be done cheaper than what it currently costs. I'd like to discuss the "easiest" and "cheapest" (cheapest development and single launch scenario) launch vehicle that can be built by an amateur to reach space....

Ky launched a second GoFast in July of 2014 at Black Rock...a '10th anniversary edition' using, as I recall, an out of warranty $50,000 Cesaroni motor. The photo is shortly before the launch.

https://www.flickr.com/photos/48721294@N08/14664371811/in/dateposted-friend/

Rick