getting a toy in "space"?

[mixedgas]

Find a local aircraft pilot or pilot forum. Ask them where to find your local "Winds Aloft" chart.
World wide pilots call these "metars". This will get you a idea of what your dealing with locally.


Where I live, the massive "Jet Stream" passes over my house. Anything launched here is going at least 200 Kilometers, if it gets to 20,000 or 30,000 feet. Most people here drive west to launch their Balloons so they don't land in the hills and mountains to the east. They make it a party and do it in groups.

It makes sense to find others who are technically interested and do this as a group...

Here, They use both cell phones and two meter (144 Mhz) band amateur radio for tracking. They use 440 Mhz, 1.2 or 2.4 Ghz band analog video for the camera. We know the jet stream usually runs west to east, so they drive 200-300 kilometers west and announce the launch a few weeks in advance. As nearly every amateur radio operator world wide has a 144 Mhz handheld radio, tracking is fairly easy. If I were not here, I'd use the 14 Mhz or 28 Mhz amateur bands. (Amateur radio uses those bands in more restrictive nations) If you know anything about electronics, getting the amateur radio license is easy, in 90% of the world. When your balloon is going high, 100 mW is a lot of power and can be easily heard for 50-100 Kilometers.

I don't know which app they use. Most cells with a GPS can be set to SMS or broadcast their position. I'd find a disposable cell phone, here, that is easy. I'm not so sure about Asia.

If you can't do the phone.....

300 meters of 30# test strength Dyneema fishing line weights less then half a Kilo, costs 5 Euros on Ebay..... 15# test strength Dyneema is half that weight. How old is your kid? 10-12 year old is going to be just as happy with a tethered flight.... 1.6 Kilos of lift on a weather balloon,,,, Just a idea...... :-)

Amateurs, cheap toy store impure helium, and a heavy go pro camera. Go far into the videos, both have BS for the first half.

http://www.youtube.com/watch?v=T_WuAZkVo_w

http://www.youtube.com/watch?v=kJGAbowUtHw

If I were doing that, I'd get a few 16$ big Balloons, some 7# test Dyneema, a memory stick camera, and I'd add a little parachute just in case. A little piece of cardboard as a fin would make sure the camera points into the wind. I'd put my name and address on the camera on heavy plastic just in case. :-)


I'm a "Helium Fan", here is why. Meet my next door neighbor since childhood:

http://www.goodyearblimp.com/cfmx/web/blimp/





Steve

[kecked]

hydrogen is safe so long as you use a good ground. Unfortunately the latex in a balloon likes to make a lot of static. If you can fill it remote and then release it remote, it will be safe. If you don't get air in it that is. If you make an air hydrogen mix your going to break windows for a good block.

The only reason I bring this up is that helium is a finite resource and we are running out. The days of ballons in shopping malls is numbered.

While your at it mount a small strobe on it and launch at night! If you are in the USA I think you need t call FAA to get a launch window.

There is a whole column in Nuts and Volts magazine devoted to doing this. They have a complete design. One issue they found was when it bursts you have to make sure ALL equipment is bolted to the chassis or it comes free and scrambles everything breaking it to dust. Apparently the tumble is very violent.

[mixedgas]

You got me interested, I just found a disposable 2 meter transmitter module on ebay for 13.50.... I ordered one...
The Sirfstar GPS is a few grams....


Steve

[kecked]

steve I wonder if you could add some station keeping to the system so you can control where it goes. Add some control surfaces to add spin for the way down. That should keep it straight at least. Use a high speed camera system and you can take the spin out with processing.

[TechJunkie]

I dont know what documentary you've seen, and if you can find it on the internet then please link it, but I'm guessing it is old when all the technology in these new tutorials didnt exist, werent available to everybody or were just a lot more expensive or they used different stuff.

Don't get this the wrong way, I understand that theres a large possibility it will get lost, end up in an inaccessible place, etc. but I dont think Ill likely be spending "several thousand dollars" either.

I combed the internet, and could not find it. Its really bugging me now. It was not old tech because they used a GoPro. If you add up 7 GoPro cameras, 7 helium filled weather balloons, and assorted hardware, it can easily go into the thousands if you lose 6 launches. By your own estimate of what helium costs where you live you can easily see it go into the thousands if you try multiple launches.

The fake UFOs we launched moved extremely fast through the lower air level. Approximately 1 mile in well under 60 seconds. As Steve said it could get really moving in the jet stream. Its a short hop between where I live, and two other states. Not including the ocean. So from my perspective it could fly across a couple of states.

I'm not saying not to do it. My only point being its a commitment. It all comes down to how much time/money you want to spend to impress your son.

Looking forward to your video. Good luck.

[kecked]

equilibrium is about 1.1 kg/m^3 of gas so you'd need at least 0.6 m^3 of gas to lift 500g. That isn't much at all. In fact I think 4-5 regular mall balloons would do the job. More means it rises faster and one would assume straighter. Tape them together to make one large lifter.

[Laserman532]

[mixedgas]

Quality Parachutes for when the balloon bursts:

http://www.the-rocketman.com/recovery.html

[kecked]

The boxes I've seen weigh in at a few pounds and have tons of telemetry equipment plus the cameras and powerpacks.... Your just going up pop and coming down so no need for the rest.

[mixedgas]

You guys are awesome.

is the first column the length and width of the parachute?

The first column is the diameter (width) of the parachute in feet. The second column is the attached weight in Pounds when tested. The Third and Fourth columns are the descent rate, first in Miles Per Hour (MPH) The second is in Feet per Second. The next three columns are what happens at maximum load for the parachute..

Steve