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Hello and welcome to meh little space programme! Here I will be weekly uploading about my space program. Maybe I should tell you about my status as a space program. 

Ok, I'm not a real space program owner but hey, maybe one day I will be! Ok, back to the topic, I live on a farm with a airspace that VERY rarely planes pass across.this kinda means that for my rocket launches, I will not need to have airspace cleared or anything. so that means I won't really have a time restraint, meaning I won't have to finish a rocket on time. Also, because I live on a farm, many chemicals are available (because they are used for put killing), but this doesn't necessarily mean they are perfect for using rocket fuel. Also this thread is linked to my other thread:

 Ok, now lets cut to the chase, and I will start posting my status as a space program!

PROLOGUE 

Back a few months ago I built these mini match rockets and they, because of limited time, flew 30 feet(only half of the expected 60 feet):(. I then, in the afternoon of that hot day, built these bottle rockets flying 40 metres! (80 feet?) they were made of soap, water and local air(dat stuff you breathe in:cool:). We did so many launches that I could not even count!!!(I'm guessing like 80 launches or something) then we started experimenting with petrol! *evil grin* to put it, the petrol we used was not explosive, between it came out it burnt everything it lands on because of the Bunsen burner used to light the petrol up. After this I went into a period of long research...

August 13th

So today I was looking in the ol' PVC and adapters parts and I found the perfect piece for a hybrid rocket motor! Then I burnt one end with a Bunsen burner until it was alight. then I quickly used an O2 tank as an oxidiser which then created a very hot exhaust... The flame actually turned blue at a point too! I think hybrid rocket motors are the way to go if you are beginning a space programme!!!

 

Sorry I’m discontinuing this

...

Edited by Shadow Wolf56
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6 minutes ago, Shadow Wolf56 said:

Oh, I thought there wasn't. I'll take a read...

There have to be one at least. Unless you live in a far less sovereign and peaceful nation.

IMO as long as it don't go close to above the height of holding patterns (as low as 1500 feet (500 m) above runway altitude) they should be fine. Or as long as your family isn't tending the ranch in a plane.

Edited by YNM
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This sounds really cool, and a lot of fun, but- remember, rocket fuel is dangerous. Always be careful about how you deal with it.

Maybe you'll eventually have a rocket big enough to launch a small camera or other payload? Say, a little aluminum foil man?

Edited by cubinator
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Just on the safety side of things, a quick skim though the above CASA documentation highlighted the following passage:

Quote

WARNING: Never use home made motors or motors not recommended by the kit manufacturer. Homemade motors would be considered an unauthorised explosive under state and territory explosives acts. This usually carries a mandatory $10,000 fine! Furthermore such motors have been known to cause serious injury and death

So if you're planning on making home-made rocket motors, you'll have to get government approval first, otherwise you're technically making illegal explosive devices. By the look of it the only rocket motors you're allowed to use in Australia without prior government approval are kit motors.

 

Also, if you want to launch anything that weighs over 1.5kg, is powered by anything more powerful that an H-class (320 Ns impulse, which is pretty big for a model) motor or has a metal construction, it's classed as a high-powered rocket, which means you'd have to be certified.

Quote

Potential operators of high power rockets would be required to undertake certification prior to being permitted to operate such rockets. Certification would be in two steps administered by an Approved Aviation Administration Organisation.

 

Finally, there may be additional state regulations to look out for in addition to these CASA ones.

Edited by Steel
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On the safety-experience-advisory side as well, it's probably better to contact local / national bodies once you reach rocket sizes large enough to reach kilometres up. I found this forum referred from this organization. You can put up things and ask here for design and such, but for the really legal sides and experiences you should ask your fellow australians.

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  • 4 months later...

awesome! are you still into rockets?  

I've been playing with China's l vinegar / sodium carbonate rockets myself. they only go up as far as 20 meters or so..

I've been thinking of making candy rocket fuel but launching them in the Netherlands is illegal.  also... working with potasium nitrate is pretty darn risky 

 

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3 hours ago, xendelaar said:

awesome! are you still into rockets?  

I've been playing with China's l vinegar / sodium carbonate rockets myself. they only go up as far as 20 meters or so..

I've been thinking of making candy rocket fuel but launching them in the Netherlands is illegal.  also... working with potasium nitrate is pretty darn risky 

 

I'm tempted to give advice on how to improve performance, the problem is that just about any redox reaction is too dangerous to play around with. high energy redox reaction don't proceed like other chemical reactions as they generate heat and also free radicals that can greatly accelerate the rate of reactions, they go critical.

If you are creating an SFRB you need to remember that confinement is your primary problem, and the fuel needs to be in a matrix in which your can control mass flow and acceleration.
The second is your primary concern in the testing side, so you don't even need to launch, you can have a rocket in a jig with a spring type scale attached to measure the force production over time.

You don't have to go solid, you could use two liquids, such as hydrogen peroxide and hydrazine. H202 is problematic in that in storage and preignition flow it needs to be kept stable. Typically H202 is shipped at 68% relative to water or less, which would lower the ISP,  but also lower nozzle temperature and increase the overall work efficiency of the blast.  If it is kept cool and hydrated you can consider it to be stable. 68% H202 is hard to get outside of an industrial or research setting. Hydrazine is also unstable in the anyhydrous form, so you also want to keep this in a stabilizing solution, although it does not need to be water, water makes mixing with H202 somewhat more convenient since it is like water and in water. And if you get this proper, igniting this without blowing yourself to high heaven is the issue.

SO I want to tell you a story. Once upon a time, in my old lab I had a researcher that claimed that the b-mercapto ethanol we was using was bad. So I took 10 ul of BME and 10 ul of a 30% solution of H202 and placed it in 1 ml of water. So both oxidizer and fuel are at a 1:50 ratio of what an actual mixture in a rocket would be. After about 20 seconds he began repeating, "look its bad, see bad" at about 45 second it blew then entire contents of the liquid out of the test tube without leaving a trace of liquid. BME is not an ideal fuel and having a 50:1 ratio of deadwood did not stop the reaction, its only SLOWED it down. That demonstrates the potency of liquid redox reactions.

Vinegar and Baking soda is an acid base reaction, its not  a redox, when you think about reactions think acid base is to redox what redox is to nuclear, its intermediate in magnitude between those two.

Since obviously you cannot reach above 10km altitude you could, with modern lithium batteries use a series of fans just like on a gyrocopter to compress air, compressed air at very high levels is extremely explosive (you could theoretically ignite air, and that is the big risk of decapping pressurized Oxygen, but you would not be reaching those pressure). This is essentially a turbo jet but without the turbine. This is very old hat, Rudolf Diesel demonstrated this at the Chicago's worlds fair by compressing cotton in a glass tube and a plunger, causing the cotton to explode. Cotton is essentially a chain of sugar, therefore any starch or sugar water solution would suffice. The good thing about this system is that oxygen flow is powered, meaning that if the sensor wire is rapped around the pre-expansion chamber, a failure in preignition dislodges a solenoid and stops airflow the wires and terminated the reaction (to STP levels), all you have to do to lower risk is have good fuel containment. But what is the best fuel . . . .ethanol would be a suitably good liquid fuel for burning in a pressurized air system. On a compressed air system you want a closable aperture at the head of the rocket that controls air flow, this also would improve aerodynamics. You can potentially make the system safer by lowering the percentage of ethanol in water to 60% and use a tiny amount of something that autoignites well in pressurized oxygen to initiate the preignition. Something like HPLC tubing feeding the highest heat point of the compressed air.

So the risk of methanol and ethanol can be stated as such . . . .more dangerous than gasoline . . . . .gasoline has chemical impurities (benzene, toluenes, meta-xylenes) that are harder to burn and produce less heat than ethanol. Methanol can be easily stored in a relatively explosion resistant chambers but I have seen the following even occur twice, one resulting in injuries. The most dangerous situation for contained methanol or ethanol is not a full canister, its a canister that is almost empty, that gas air mixture flows out heavy (in the case of ethanol) and runs along a surface until it finds a flame, the flame travels into the cansister and where the container ignites and becomes its own rocket (much better than your 10 meter rocket). So you definitely don't want oxygen or air to be used to pressurize the methanol tank. However you could use a chemical resistant baffle that is spring tensioned to provide pressure.  Methanol has the same molar mass as O2 so that it will flow out and mix with air more readily. Methane of course, I have seen two houses that were converted to match-sticks because of methane. If you can get it, methanol may be the best choice. 

Of course if your batteries are powerful enough you don't need methanol, just compress the air at very high pressure, and at its highest pressure heat it another 1000 degrees. Another way to do this is to preignite a very fuel rich mixture around the oxygen tube and spray that into a reaction chamber for ignition.

There are lots of ways to make  a rocket, very few of them are safe, so its better to start very small and test your way toward better designs. You don't need to be in restricted airspace to test the designs.

 

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