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Update: September 30th, 2005 After 6 months and 7 days lost in action, the balloon has been recovered. The above high altitude photo of Melbourne is but one of the great shots that were developed. Note the spot of condensation. See below in red for details!!
Air safety:The first thing that everyone was saying when I mentioned my project (and probably what you are thinking right now) is air safety. A helium filled balloon is capable of rising to a ridiculously high altitude. Around 100 000 feet is not uncommon. That altitude is officially classified as near space. It is above the troposphere and tropopause. It is the stratosphere. There is very little air density, and looking at the horizon, the Earth's curvature is clearly visible. The entire state of Victoria can be seen in one piece. There is little wind, as it is far higher than the usual jet streams which occur at around 34 000 feet. So to get there, the balloon has to go through air space which is populated not only by little Cessna airplanes, but also by passenger jets cruising at 800 km hour. Doing some research on the legalities, I found that Australian regulations were seemingly lenient in terms of the requirements that the balloon would have to meet. The full document can be downloaded here: (I hope they don't move it) www.casa.gov.au/rules/1998casr/101/101casr.pdf The Civil Air Safety Authority (CASA) extract 101.145 applicable for balloons states that there are four classifications for helium filled balloons. Small, light, medium and heavy. The larger the balloon the more stringent the regulations for it. Small balloons are just standard party balloons. They pose little risk unless in very large numbers. Light balloons must not carry more than 4kg of payload, medium balloons 4-6kg, and heavy 6kg plus. My balloon would fall under the light balloon category. This required me to adhere to a few rules, but was not very stringent compared to medium and heavy balloons which require constant RADAR tracking etc. The requirements as I understood them were to: 1. only release the balloon in a non restricted area. (not close to an airport) 2. to provide CASA with name address and phone number, date and time of release, place of release, estimated size and mass of payload at least 1 day prior to release. When I rang up to notify them, the gentleman on the phone didn't quite sound like he knew what to do. Indeed, this was after a handful of calls to find out who should actually take the information down, and which office was responsible for the task. No doubt this was his first call of this nature. He ended up giving me permission, but I don't recall him asking my name, address and phone number. Most of the questions were with regard to the payload size and were probably just out of his own curiosity.
In any case, I had CASA approval to launch the balloon at 7am on Saturday 19th
March, 2005. My friends Paul and Viktor came out to see it go. My housemate
Jason was to stay at home and relay Melway references via this site:
http://services.land.vic.gov.au/landchannel/content/interactivemap Note that at the bottom of the site, the degrees, minutes, seconds of the latitude and longitude change as you move your mouse around the map. I launched it at the park just across the road from my house in Reservoir, Victoria, Australia. The payload (balloon 1):
The payload was a 35mm camera with motorized auto advance. 24 exposure film.
The payload could rotate 180 degrees to take vertical pictures of the earth,
horizontal pictures of the horizon, and vertical pictures of the balloon
itself. The camera was triggered by another servo which pushed down on the
camera button. It was programmed to take pictures every 4 minutes. The
payload also included a GPS receiver (hacked from a Rand McNally palm III
attachment also from ebay) and a Nokia 3350 mobile phone with a broken screen.
The brain was a microchip microprocessor PIC16F88-1/P with
a picaxe 18X loaded bootstrap program. It interfaced the GPS with the
phone and controlled the two servos that actuated the camera. It relayed the
GPS coordinates through DTMF signals as created by a 5089 DTMF IC. Want to
know more about the payload? Click
here.
The launch (Balloon 1):The morning came, and sleepy eyed, I awoke to some very appropriate ballooning weather. There was no wind at all, and only a slight scattering of clouds. The report from the previous day stated we should expect 34 degrees Celsius, with light fog in the morning followed by no clouds and blue skies throughout the day. A high pressure system was directly over us, which I am told generally suggests that the jet stream winds in the upper troposphere will be pushing the balloon North to North East. This is perfect as it would push the balloon away from Port Phillip Bay, and away from dense civilisation. More info on the troposphere, tropopause and stratosphere here: http://www.answers.com/topic/tropopause
It was lifted by a 200gram meteorological balloon that I bought on
ebay. It had a reported diameter of 6 feet. We blew it up to about 5 foot
diameter = 150cm diameter with Viktors helium. This gave us about 1 kg of
lift. We thought there would be more helium in the tank than there was. (the
helium in the tank was the remainder of what Viktors work used
during their advertising fair the previous weekend) Consequently, we had
to ditch some weight off the payload. The parachute was rather large, so we
cut it down to size, enough weight was shed to give us about 300-400
grams of free lift. That's about 500 feet per minute ascent. Not very fast,
but had to do. (usual rate of ascent should be double that)
The original plan was to attach two balloons to the payload. I had bought 3 from ebay (nice guy from Hawaii), and we had guestimated that we would have enough helium to do this, but alas, it turns out we didn't.
After filling the single balloon, a check of the GPS tracker and other
equipment was done. We had some problems with the servo not pressing enough on
the camera button to take photos. Also, the GPS tracker was only
reporting a position every minute or so. That was strange because the night
before, I had tweaked the microprocessor code to give updates every 20
seconds. (I had worked all night on that till 5am!! and I had tested it before
hand!!) In any case it was now or never, so we let it go at about 9.30 am. Any
further delays would have possibly required re-arranging permission from CASA.
The balloon went up seemingly rather quickly. It traveled East then South East then Nor Nor East, and continued in this direction for a while. We said goodbye to Paul, and Viktor and I jumped into the car to start tracking the balloon.
About 5 minutes after launch, I called the balloon to get a position fix. I
was rather surprised to learn that the balloon was already out of mobile phone
coverage. I had expected to lose mobile phone coverage, but only after more
than 30 min flight time, and at over 30 000 feet altitude. That was
rather disheartening, but I still hoped that I would be able to track it once
it came down to earth.
We saw the balloon climb to a very very high altitude for over 30 minutes, and decided to abort tracking by car, as we had no GPS coordinates to do so. The balloon then crossed over the sun, and we could no longer look at where it was. That was the last time we saw the balloon. We drove back to my house.
I called every half hour from then on hoping to get a fix once the balloon
landed. The phone kept diverting to message bank indicating it was out of
range.
At exactly 1pm, I called and the phone answered. This indicates that the
balloon was at that moment either on its way down (and very low) or
already landed (probably the latter). It also indicates that the hands free
attachment was at that time still in the phone. (the phone does not auto
answer if the hands free is not in) However, all was not well. There were no
DTMF signals from the GPS nor was there a single beep (a single beep indicates
that the GPS is working but not yet locked on to a fix). This indicates that
the GPS was not powered up or not connected at all. I listened in for about 1
minute during which time I heard some light clanking sounds and some light
wind. The phone then cut out completely, and I have not been able to call it
again (diverts to message bank).
Postmortem (Balloon 1):
My hypothesis is that the payload must have crashed rather hard, and that the
GPS failed due to the impact.
With regard to the phone dying while on the call, I believe that it simply ran
out of battery life. The battery of the phone has (had) a good standby time of
at least 4 days and a good talk time of about 2 hours and it was fully charged
when it left the ground. However, I believe that while the phone was in the
sky, it was continually trying to communicate with various passing towers,
thereby decreasing its standby time. As the flight was rather long (approx 3
or 4 hours) , this could have drained the battery prematurely. Another
possibility is that moisture built up inside the phone due to reentry into
warmer moist air. Your guess is as good as mine.
The next one:So as I write this, one day after the launch, I am already planning another flight. The failure of this flight has only fuelled more determination in me. The most enjoyable part of the experience is the feeling you get just after the launch. Until that time you are making decisions on about a thousand things, and you can affect what is going to happen. But after you release the balloon, all of that stops. You are completely at the mercy of chance.
I have two balloons left, and I am thinking about doing this again with some
changes to the setup:
- use mobile phone again but only turn on mobile phone after 3 hours.
(after it has landed) Either that or use UHF radios with directional antennas.
- no servos to tilt the assembly. They are rather heavy and the tilt assembly
itself is necessarily rigid and therefore heavy. Camera to be fixed for
horizon images only.
- delay taking any photos for first 30 minutes of flight. Then take
photos every two minutes. (use 36 exposure film this time)
- have externally mounted weatherproof switch that activates timer just after
takeoff.
- lighter camera with a different (lighter) actuating mechanism (no servos)
- generally smaller payload for less helium/ hydrogen and therefore
higher altitude.
- GPS to send last known fix data if it is not locked on to satellites. This
will at least give me an idea of where it landed if it lands upside down and
does not fix.
- rounded payload with dint on the bottom. (like a half flat basketball) so
that there is a better chance of it landing vertically, and therefore a
better chance of a GPS fix.
UPDATE!!
The balloon has been found and recovered on Friday the 30th of September, 2005!! I had completely given up the thought that it might still turn up, but 6 months and 7 days later, I received a phone call from Alexandra police station. A caretaker had stumbled across the payload during his rounds. He opened the payload and rewound the camera, then promptly handed it in to the local police station. A detective (!) looked at the payload, and cut the wires from the battery, and also the GPS wires going from the GPS board to my microprocessor controller picaxe board. I wonder what was going through his mind at the time!! Confirming that the payload was safe (and not a nuclear, chemical, or other weapon!!), the police then recharged the phone, and called the last number dialled............ which was me!! Needless to say, I drove to pick it up the first chance I got. Which was today (Friday the 30th September). The police man was very nice and not the least bit scorning. I was hoping for that, as it could have been quite a different story! He explained that the caretaker that found the parcel did not open the camera. This was great news, as the chances of getting some photos were looking better and better. Of course, on my way home, I had to stop off at a 1 hour photo shop to get those photos developed. I am happy to say that every single shot from the 24 exposure film was all there!! One minor letdown is that almost half of the film was wasted by shots taken on the ground. But hey, who's complaining, I got the film back!! So here they are in order. Again, sorry if you have dialup. These are large files. I have taken out the 8 shots of grass, which would have been taken while we were working on the parachute.
This payload had the ability to swivel the camera from horizontal to vertical. Every 5 minutes, it would take a horizontal shot, then a vertical shot. As the day was nice and sunny, great detail can be seen in the original photos. Here are some pics of what the remainder of the payload looks like:
Above. That's how the police gave me the electronics. All in bits.
Above: The tangled parachute cord shows that the payload must have had quite an impact
The impact must have ripped out the tilt servo. Thankfully, I used a cable tie to tie all the equipment together.
Any other suggestions or comments? Email me philippawlowski at hotmail dotcom
Thanks to the following people that made this happen: Insight Publications for donating the helium for the project. http://www.insightpublications.com.au/ Rhonda, my partner, for making the parachute. Paul, for donating the two servos and helping out on the day. Jason and Viktor for helping out on the day. CASA for not being too stringent and limiting in their approval process. Jim from Jim's hire that donated the DTMF IC free of charge. Good bloke. http://www.jimshire.aussiewide.com/ APMP for funding most of the project. Alexandra Police for being nice enough (curious enough?) to do some detective work to track me down.
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