Going to Space?

[OverlordvI]

I've been doing some back-of-the-envelope calculations, but I wanted to see what you folks thought...

What kind of motor combination would you need on a light payload to make it 62 miles into the air? The SRBs on the shuttle are type X (X 10,485,760.00-20,971,520.00 - Space shuttle SRB) but the shuttle also weighs a few tons...

Could a parallel cluster of 5 off the shelf O's each with a serially attached O as the SRB on a second stage O be enough to get anywhere near the big unknown?

 

[heada]

Check your FAA/AST(CST) regulations. I think you'll find a limitation of up to 200,000 lbf of total thrust allowed per flight. Add up your 10 O motors and see if you're still below that limit. Then check to make sure the 5 O boosters can safely lift the sustainer 5 O motors and all the required rocket to support them.

-Aaron

 

[OverlordvI]

Well, this is all in theory .

I'm just thinking ahead... I have a long way to go before I even have the experience and skills to do something like this...

 

[r1dermon]

CSXT did it as basic and minimum as possible. and that thing was HUUUGE. lol.

 

[Chrisn]

There is more to a space shot than strapping the biggest motors you can buy together. that many motors of that size is also asking for trouble, keep it simple and have a single motor and/or to a single motor sustainer

 

[Chrisn]

Check your FAA/AST(CST) regulations. I think you'll find a limitation of up to 200,000 lbf of total thrust allowed per flight. Add up your 10 O motors and see if you're still below that limit. Then check to make sure the 5 O boosters can safely lift the sustainer 5 O motors and all the required rocket to support them.

-Aaron

With that much money to burn im sure one could afford to take launch operations to another country, or get the required permits/permissions to proceed

 

[nxj]

Or just pay to go up with the Russians.

 

[jadebox]

CSXT did it as basic and minimum as possible. and that thing was HUUUGE. lol.

The Civilian Space eXploration Team used a single S motor. That's the equivalent of about 16 O motors. But, they didn't stage their rocket so maybe five O motors staged to an O would do it. Will Rocksim handle modelling that?

-- Roger

 

[bobkrech]

I've been doing some back-of-the-envelope calculations, but I wanted to see what you folks thought...

What kind of motor combination would you need on a light payload to make it 62 miles into the air? The SRBs on the shuttle are type X (X 10,485,760.00-20,971,520.00 - Space shuttle SRB) but the shuttle also weighs a few tons...

Could a parallel cluster of 5 off the shelf O's each with a serially attached O as the SRB on a second stage O be enough to get anywhere near the big unknown?

It depends totally on the design of the rocket, the payload requirements, the mission profile and a budget in excess of $100,000.

The cheapest way to assured success is to purchase a sounding rocket. https://rscience.gsfc.nasa.gov/ Sounding rockets such as the Loki Darts (52,500 Ns or 28% P) routinely achieved these altitudes on a daily basis in the 50's. https://en.wikipedia.org/wiki/Sounding_rocket https://www.designation-systems.net/dusrm/n-12.html Two stage boosted Arcus rocket also hit these altitudes. The Arcus was a 98% O (~40,600 Ns) rocket and the booster ranged from 75% O (35,910 Ns) to 69% P (69,400 Ns) https://www.designation-systems.net/dusrm/n-6.html

There have been 2 successful space shots by amateurs. The first was by the Reaction Research Society https://www.rrs.org/main/ back in the days when the space boundary was 50 miles. The second was the GoFAST team as previously mentioned.

The next big amateur effort is the Sugar Shot 2 Space effort. https://www.sugarshot.org The rocket will ascent ot over 100 km powered by a unique dual-burn single-stage motor design that will allow a low specific impulse KNSB (potassium nitrate - sorbitol) propellant system to get the rocket through most of the dense lower atmosphere by coasting. The impulse of the motor is ~58,200 Ns or a 42% P.

Bob

 

[Pyro Pro]

I did a design once staging an N4800--N4800--K250 (All in all, barely, barely more than a full O; 100.34% O, or a 0.17% P), and using lots of really long ignition delays on the various stages (14 sec delay on the second stage, 23 second on the third), got it to simulate out to nearly 337,000 feet (63.8 miles). Not sure how accurate that figure would be, not to mention the design is so long it would probably fold in half or at least not go up perfectly vertical, but it's just a simulation...

View attachment 989854alt.rkt

 

[OverlordvI]

The next big amateur effort is the Sugar Shot 2 Space effort. https://www.sugarshot.org The rocket will ascent ot over 100 km powered by a unique dual-burn single-stage motor design that will allow a low specific impulse KNSB (potassium nitrate - sorbitol) propellant system to get the rocket through most of the dense lower atmosphere by coasting. The impulse of the motor is ~58,200 Ns or a 42% P.

It sounds like I may be in the ballpark in that case. Instead of O's, using a reliably manufactured higher rated engine with a well designed light rocket could probably do it. Apart from getting the administrative stuff taken care of, it sounds like the biggest hurdle is probably money?

If $100,000 is an estimate for the multistaged O's, what do you think a well-designed PQR or S rocket would run?

 

[r1dermon]

depends who your manufacturer is...how much R&D you put in (test firing...etc..) this isn't exactly something you just get up one morning and do...it takes YEEEEAAAARS of planning and experimentation...it's not as easy as saying hey, lets build an S motor, a frame, and a tower, and launch this sucker. my guess is that a million dollars TOTAL is what you're looking at minimum. i base everything off of CSXT and that's what it cost them. as far as being bare minimum, i still think that's about as bare minimum as you could get while staying with the old KISS approach.

 

[OverlordvI]

There's something that I don't understand. I've been looking at the links that Bob posted and looking into the Black Brant sounding rockets. Take a look at this:

Black Brant III

* Payload: 18 kg
* Maximum flight height: 177 km
* Thrust: 49 kN
* Mass at launch: 286 kg
* Diameter: 0.26 m
* Length: 5.50 m.

That rocket goes about 110 miles into the air with "just" a P motor.

Black Brant VI

* Maximum flight height: 72 km
* Thrust: 7 kN
* Mass at launch: 100 kg
* Diameter: 0.12 m
* Length: 2.80 m.

That one goes to almost 45 miles with an M class motor.


What am I missing here? What is different or special about their particular motors that isn't available off the shelf for us? Is it the total amount of time that they fire?

 

[OverlordvI]

FYI, my source was Wikipedia for the above. I know, not the most reliable, but I don't know where else to look.

While I'm at it, are there any specific references I can look up to learn more about sounding rockets - i.e. any good books out there?

 

[jadebox]

That rocket goes about 110 miles into the air with "just" a P motor. ... Is it the total amount of time that they fire?

Total impulse is in Ns (Newton-seconds). You have to multiple the thrust in Newtons by the thrust duration in seconds to get the total impulse in Ns. So, "yes" is the answer to the last question.

-- Roger

 

[brianc]

While I'm at it, are there any specific references I can look up to learn more about sounding rockets - i.e. any good books out there?

From ye'ol Bookmarks file (not all are sounding rockets)-

https://history.nasa.gov/SP-4401/sp4401.htm
https://www.designation-systems.net/dusrm/
https://www.astronautix.com/index.html
https://www.skyrocket.de/space/index_frame.htm?https://www.skyrocket.de/space/launcher.htm
https://www.sat-net.com/serra/index_e.htm
https://missile.index.ne.jp/en/
https://www.fas.org/man/dod-101/sys/missile/



For books, I recommend the (newly republished) Rockets of the World along with the supplements.
https://blastzone.com/nar/narts/store.asp?groupid=1080035015601

Small Sounding Rockets from ARA Press is good, especially if
you're a rivet counter like me. However, it's currently sold out (OOP).
https://www.arapress.com/ssr.html
Some photos from the book-
https://traxellabs.com/smallsoundingrockets.org/photos.html


Rockets Over Alaska: The Genesis of Poker Flat (also from NARTS) looks interesting, but I don't own a copy.


Also, you might want to check into the Flight Operations manuals for
the various facilities (just to get an idea of the hoops you need to jump
thru) Here's the one for Wallops Island-
https://ww1.wff.nasa.gov/multimedia/docs/wffruh.pdf




HTH!

 

[bobkrech]

They're just standard motors. What you missed is that Total Impulse = Thrust x Burn Time

The complete info is shown below for two Black Brant sounding rockets.

Black Brant III
First Launch: 1962
Retired: 1984.

* Payload: 18 kg
* Maximum flight height: 177 km
* Thrust: 49 kN
* Burn Time: 9 seconds
* Total Impulse: 441000 Ns = 35% S
* Mass at launch: 286 kg
* Diameter: 0.26 m
* Length: 5.50 m.

Black Brant VI
First Launch: 1972
Retired: 1979.

* Maximum flight height: 72 km
* Thrust: 7 kN
* Burn Time: 9 seconds
* Total Impulse: 63000 Ns = 54% P
* Mass at launch: 100 kg
* Diameter: 0.12 m
* Length: 2.80 m.

https://www.astronautix.com/lvs/blabrant.htm

 

[OverlordvI]

Brianc and Bob, thanks for the great links, and Jadebox and Bob for the clarification.

54% P and going up to the edge of space (44 miles) is very impressive! Here is another question (I apologize for my ignorance) - what is stopping someone from buying two P motors from Loki Research, putting them in serial, and doing a shot into space for under 10 grand? (apart from the FAA restrictions, clearance, etc.)

 

[bobkrech]

Brianc and Bob, thanks for the great links, and Jadebox and Bob for the clarification.

54% P and going up to the edge of space (44 miles) is very impressive! Here is another question (I apologize for my ignorance) - what is stopping someone from buying two P motors from Loki Research, putting them in serial, and doing a shot into space for under 10 grand? (apart from the FAA restrictions, clearance, etc.)

It's really not that impressive. This is 60's technology.

What the individual doesn't have is the technology and the infrastructure. While a set of motors may cost ~$10K, you are totally neglecting the rest of the costs of a space shot.

You need the rocket, the launcher, the electronics, the communication equipment, the explosives permits, the transportation costs, a few motor homes, and other vehicles, and more importantly the launch permits and a launch site.

You will have to perform all the safety analysis for a commercial spaceflihgt and have all the safety/communications infrastructure to conduct a spaceflight. You can count one one hand the launch site locations from which you could conduct your flight ops. You would need a team of at least 12 folks and have to transport them to the launch site and support them at the launch site for 1 to 2 weeks.

Whether it's your personal money or money you collect, you can't do all this for under $100,000.