I am a contestant for the M-Prize challenge

[Cyrus]

Yea he is a biology guy but he's also an amateur rocketeer

So then he isn't a "top scientist" in terms of aerodynamics. Is it even legal to put something into orbit?

 

[Iyafrady]

This is a video of the south african team's test launch.

http://www.youtube.com/watch?v=FKIXouBIyyI&feature=channel_page

 

[signerror]

and it is possible (if you have budgeted for the lift-mass of the oxidizer) to use hydrogen peroxide for attitude control.

Minor correction, monopropellant hydrogen peroxide is not used as an oxidizer (no redox reaction) - it is rather a catalyzed decomposition, which probably involves radicals (unpaired valence electrons).

H2O2 -> H2O + 1/2O2

 

[Cyrus]

Instead of building this thing like a bunch of yahoos, has anyone sat down and did some actual orbital calculations to make sure you all are not wasting your time chasing a pipe dream?

 

[Iyafrady]

Instead of building this thing like a bunch of yahoos, has anyone sat down and did some actual orbital calculations to make sure you all are not wasting your time chasing a pipe dream?

Of course we plan to do orbital and gravitational analysis but unfortunately Greg (one of the main developers) got grounded for a couple weeks so he can't use his computer, so that part has to be put on hold.

 

[Cyrus]

Of course we plan to do orbital and gravitational analysis but unfortunately Greg (one of the main developers) got grounded for a couple weeks so he can't use his computer, so that part has to be put on hold.

He got grounded? How old are you guys...really. It's ok if you guys are in high school.

 

[signerror]

Instead of building this thing like a bunch of yahoos, has anyone sat down and did some actual orbital calculations to make sure you all are not wasting your time chasing a pipe dream?

Well, from 0th-order theory there is no issue, e.g., the rocket equation is invariant under scaling of the rocket. If you could shrink a Delta rocket uniformly by five orders of magnitude, it would still have enough propellant to go wherever a full-size Delta could go.

But then I don't think you can shrink a Delta rocket by five orders of magnitude. I'll defer to you engineers to explain exactly why.

 

[G01]

So the girl reaper was your fault?

I always assumed a graveling in space knocked that toilet seat loose.

That was a great show.

 

[Iyafrady]

Team Prometheus

 

[Cyrus]

Well, from abstract theory there is no issue, e.g., the rocket equation is invariant under scaling of the rocket. If you could shrink a Delta rocket uniformly by five orders of magnitude, nothing would change: it would still have enough propellant to go wherever a full-size Delta could go.

But then I don't think you can shrink a Delta rocket by five orders of magnitude. I'll defer to you engineers to explain exactly why.

I don't follow. An Estees model rock is shrunk down, and it aint going into space.

 

[signerror]

I don't follow. An Estees model rock is shrunk down, and it aint going into space.

Well it's not simply an scaled-down Delta rocket, is it? The design is (I assume) completely different: it is solid fuel, it is not staged, it probably has a much higher rocket mass/propellant mass ratio, and so forth.

At the 0th-order theory, simply dealing with conservation of energy/momentum, there is no scaling behavior in this equation:

http://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation

The question is, where does scaling come in? I'm not an engineer, I have no idea. My guesses are it's a structural mechanics issue, or a stability issue involving moments of inertia, or fluid mechanics in the rocket engine, or heat dissipation, or something else that is not scale-invariant.

If you made a perfect scale-model of a Delta that was one inch tall, it would accelerate to orbital speeds. It's the premise that's bad: you can't scale a rocket down to an inch. The walls would be thinner than paper, and it would collapse onto itself.

 

[Cyrus]

Well it's not simply an scaled-down Delta rocket, is it? The design is (I assume) completely different: it is solid fuel, it is not staged, it probably has a much higher rocket mass/propellant mass ratio, and so forth.

I see. I thought you meant only a geometric scaling. You also meant the bold.

At the 0th-order theory, simply dealing with conservation of energy/momentum, there is no scaling behavior in this equation:

There is scaling effects with drag, which is a huge source of power loss.

 

[signerror]

There is scaling effects with drag, which is a huge source of power loss.

Yeah, but the thread is about rockets launched from high-altitude balloons, so that doesn't count.

 

[NBAJam100]

You'll all be jealous to hear that I am a contestant for the D-Pants challenge-

http://www.truveo.com/DPants/id/3889191887

 

[Iyafrady]

So then he isn't a "top scientist" in terms of aerodynamics. Is it even legal to put something into orbit?

well first I need FAA clearance to fly anything bigger than 6kg of payload but its not that hard to get for small rockets.If its too much of a hassle the rules state that the organizers won't check wether regulations have been followed so.

Anyway there are currently two ways I have an idea of confirming that the satellite has indeed reached the 100km altitude:

1 way) a long-range transceiver (currently I found one that works for 90 km! and costs as lil as $120) that transmits data with pictures from microcontroller

2 way) the thing enters the atmosphere burns up some of its components, data flash disk survives the descent (after parachute opens) and a small radiosonde turns on telling of its location...

the problem in both ways is power consumption needs...

 

[Vanadium 50]

Instead of building this thing like a bunch of yahoos, has anyone sat down and did some actual orbital calculations to make sure you all are not wasting your time chasing a pipe dream?

Building a rocket without calculations is more like "pipe bomb" than "pipe dream".

 

[Cyrus]

well first I need FAA clearance to fly anything bigger than 6kg of payload but its not that hard to get for small rockets.If its too much of a hassle the rules state that the organizers won't check wether regulations have been followed so.

Anyway there are currently two ways I have an idea of confirming that the satellite has indeed reached the 100km altitude:

1 way) a long-range transceiver (currently I found one that works for 90 km! and costs as lil as $120) that transmits data with pictures from microcontroller

2 way) the thing enters the atmosphere burns up some of its components, data flash disk survives the descent (after parachute opens) and a small radiosonde turns on telling of its location...

the problem in both ways is power consumption needs...

Im pretty sure the FAA only covers the united states. You might want to think harder about what I asked.

Second, I would worry about calculating how much energy you will need before worrying about pie in the sky stuff like long-range tranceivers.

 

[Dadface]

Dear Iyafrady,
The last time you launched a satellite it crashed in my pond and startled the frogs.I wish you the best of luck with your next attempt but please aim it somewhere else.

 

[Jimmy Snyder]

Here's the altitude record for an unmanned gas balloon.

In 2002 Japan achieved a new record: an ultra-thin-film balloon named BU60-1 made of polyethylene film 3.4 µm thick with a volume of 60,000 m³ was launched from Sanriku Balloon Center at 6:35 on May 23, 2002. The balloon kept ascending slowly at a speed of 260 m per minute and successfully reached the altitude of 53.0 km (174,000 ft), establishing a new world record for the first time in 30 years.

http://en.wikipedia.org/wiki/Flight_altitude_record"
Hot air, of course, is a different matter.
You will need a considerable rocket to make the remaining 47 km. This rocket would be payload on the balloon. I assume that any payload would have reduced the altitude acheivable by the balloon and that a rocket that could rise 47 km would prevent the balloon from acheiving the 53 km that it did. I also assume that the balloon alone cost more than $3500, or £999.99. As you go higher, the atmosphere becomes less dense which is good for the rocket, but bad for the balloon. It can't go higher without bursting. I assume that's what happened to the Japanese balloon since that's the easiest way to insure that you have risen as high as possible. It would be advisable to fire off the rocket before the burst since it would be difficult to make sure the rocket was aimed upward after the burst. But then you would take the chance of losing some of the altitude that the balloon could have given you.

 

[TheStatutoryApe]

Team Prometheus

So this is infact for the N-Prize and not for an M-Prize?
Both of the videos you have posted have been labeled for the N-Prize.
Yet your e-mail specifies M-Prize. Do you know what that's all about?

 

[redargon]

Of course we plan to do orbital and gravitational analysis but unfortunately Greg (one of the main developers) got grounded for a couple weeks so he can't use his computer, so that part has to be put on hold.

mwahahahahaa I was just imagining NASA having those sorts of problems. "Sorry boss, but we have to put the launch back a week 'cos little jimmy is not allowed to come out and play."

hahahahaa



hahahahaha


haha... ha...


*sigh*

 

[Astronuc]

Here's the altitude record for an unmanned gas balloon.

http://en.wikipedia.org/wiki/Flight_altitude_record"
Hot air, of course, is a different matter.
You will need a considerable rocket to make the remaining 47 km. This rocket would be payload on the balloon. I assume that any payload would have reduced the altitude acheivable by the balloon and that a rocket that could rise 47 km would prevent the balloon from acheiving the 53 km that it did. I also assume that the balloon alone cost more than $3500, or £999.99. As you go higher, the atmosphere becomes less dense which is good for the rocket, but bad for the balloon. It can't go higher without bursting. I assume that's what happened to the Japanese balloon since that's the easiest way to insure that you have risen as high as possible. It would be advisable to fire off the rocket before the burst since it would be difficult to make sure the rocket was aimed upward after the burst. But then you would take the chance of losing some of the altitude that the balloon could have given you.

US Bureau of Mines - http://minerals.usgs.gov/minerals/pubs/commodity/helium/heliumcs06.pdf

The estimated price range for private industry’s Grade-A gaseous helium was about $2.42 to $2.63 per cubic meter ($67 to $73 per thousand cubic feet), with some producers posting surcharges to this price.

At 60,000 m³, the cost would be $120,000 for the He, if one could get it for $2/m³. But price may be higher.

As for the rocket, one needs to size it to see how high it would get with various sizes of balloon.

This may be dated, and it needs to be verified independently. One could contact FMC Chemicals.
http://www.astronautix.com/props/h2o2udmh.htm

Dilute aqueous hydrogen peroxide is concentrated to about 90 per cent by conventional distillation. Higher-strength solutions are prepared by fractional crystallisation of 90 per cent feed stock. Estimated United States production for 1959 was 50,000 tonnes based upon 100 per cent hydrogen peroxide. In large quantities, 95 per cent hydrogen peroxide then cost approximately $1.00 per kg. In small drum lots, 98 per cent solutions cost $ 2.00 per kg. Density varies: 1.44 g/cc for 100% H₂O₂, 1.43 for 98%, 2.42 for 96%, 1.33 for 75%.

One also needs to calculate the kJ/kg of the propellant. The article also implies a bipropellant H₂O₂/Unsymmetrical Dimethylhydrazine ((CH₃)₂NNH₂), as opposed to using peroxide as a monopropellant.
This might be useful - http://www.h2o2.com/intro/properties.html


Also launch eastward, with an optimal angle toward the south or SE.

 

[turbo]

Building a rocket without calculations is more like "pipe bomb" than "pipe dream".

90% hydrogen peroxide is a very strong oxidizer, and if it comes in contact with something flammable (like something as innocuous as a greasy hand-print) and starts to dissociate, the resulting heat will cause oxygen to gas off more rapidly, then boom! Because it is so hazardous, I would expect that there are permitting requirements for its purchase, storage, and use. Certainly, the UPS man isn't going to drop off the shipment. There are "chain of custody" requirements for hazardous materials. Expect shipping costs for small amounts to far exceed the cost of purchase. Also, once the kids blow up a garage, the insurance company will have every right to refuse to pay damages and then drop any related coverages.

 

[Jimmy Snyder]

Here is another issue you will have to deal with.

For a coasting, non-propelled satellite, the lowest circular orbit with a lifetime of several hours is around 85-90 nautical miles (157-167 km). The later Apollo missions used an Earth parking orbit of about 93 nautical miles (172 km).

http://www.bautforum.com/space-astronomy-questions-answers/66070-minimum-orbital-altitude.html"
If the above is correct, then it may be that an orbit at 100 km altitude is more difficult to attain than an orbit at 150 km. But then the rocket needs to be heavier yet and will further depress the maximum height of the balloon that carries it.

 

[Jimmy Snyder]

If you could shrink a Delta rocket uniformly by five orders of magnitude, it would still have enough propellant to go wherever a full-size Delta could go.

But then I don't think you can shrink a Delta rocket by five orders of magnitude. I'll defer to you engineers to explain exactly why.

Take it from an engineer, it can be done. Last night, challenged by what Iyafrady is doing, I decided to compete myself. I asked my wife for $3500 and started building. The Delta IV is a mighty rocket 77 meters tall and capable of a top speed of 25000 miles/hour in the flats. It costs $140,000,000 to launch. In order to meet the cost requirement, I had to scale it down by a factor of 1/40000. And I succeeded. You need a microscope to see the fuel lines, but the thing is an exact replica at a height of .075 inch. Unfortunately, top speed is .62 mph, still short of what I require.

 

[Iyafrady]

90% hydrogen peroxide is a very strong oxidizer, and if it comes in contact with something flammable (like something as innocuous as a greasy hand-print) and starts to dissociate, the resulting heat will cause oxygen to gas off more rapidly, then boom! Because it is so hazardous, I would expect that there are permitting requirements for its purchase, storage, and use. Certainly, the UPS man isn't going to drop off the shipment. There are "chain of custody" requirements for hazardous materials. Expect shipping costs for small amounts to far exceed the cost of purchase. Also, once the kids blow up a garage, the insurance company will have every right to refuse to pay damages and then drop any related coverages.

Were going to get the hydrogen peroxide from Walgreens.

 

[Jimmy Snyder]

Were going to get the hydrogen peroxide from Walgreens.

You mean this 3% stuff?
http://www.walgreens.com/store/productlist.jsp?CATID=302248"

 

[physics girl phd]

Am I the next contestant for the Flight is Right? Hypatia, come on down !

The popularity and content of this thread (actual debate concerning H2O2 feasibility as fuel) disturbs me however... wasn't "The Astronaut Farmer" a bad enough movie already, without a reason to remake it?

 

[Astronuc]

Were going to get the hydrogen peroxide from Walgreens.

I presume that is for the first aid kit.

 

[wolram]

That stuff women use on their hair sends me into orbit.