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As it turned out, Friday looked to be the best day in the next several days. So on Thursday I decided to launch the next morning. John and Joel both wanted to be at the launch, but they were both working. Vern and Bill however, weren't working on Friday because of the recent rains, and agreed to help out. I wanted an early morning launch, while the ground level winds were still fairly calm. Vern was scheduled to come in at 4:00 am, and I had worked on last minute payload assembly until about 1:00 am. So I ended up not even going to bed at all, not that I would have been able to sleep anyway. A balloon launch definitely isn't as big a deal as a big rocket launch, not nearly the pressure or drama, but still a million things go through my mind the night before.
Vern arrived and we set up a flood light in the yard, then spread out a tarp over the grass. An old blanket went over the tarp to prevent abrading the surface of the balloon. Next we drug out the cylinder of helium and the fill whip. I decided not to go with a regulator on the helium tank, I had a couple of high pressure regulators that would work, but in the end I decided it would be faster just to carefully crack the tank valve open and fill directly from the tank.
Once all the support equipment was in place, we brought out the payload package and parachute, then opened up the balloon package and carefully spread the balloon out over the blanket. We used latex gloves to prevent touching the balloon, skin oils are said to weaken the balloon and there wasn't any sense in taking chances. The payload package was tied to the balloon, and I attached a safety line just in case someone let go of the balloon during the fill process.
This balloon is rather odd, when you look at the pictures you'll see what I mean. The balloon is filled from a neck on the top of the balloon, then there is a "tail" with the payload string going through the tail and attached inside to the balloon itself. That means the balloon is filled upside down, then inverted to launch. I bought these balloons as old surplus, and they are some 20 years old. Honestly, my confidence the balloon would perform was seriously in question. I really wouldn't have been surprised if the balloon didn't make to 10,000'. But I really wanted to test my radio/GPS system, cameras and other payload items. As well as gain some experience in setup and launching.
Here's Vern and I starting the fill process just before dawn.
While Vern fills, I unfold the tail section.
Here's the payload prior to the video camera being installed.
At this point the balloon is starting to support itself.
I added this label to each side in case it dropped in someone's back yard.
I'm using a fish scale to measure the amount of lift. The two payload packages and parachute weigh in at 7 pounds. I want about 4 pounds of free lift to get an ascent rate of about 1,000' per minute.
As we approach our targeted lift, I start turning things on in the payload package. The balloon is still upside down at this point.
Another shot of me working on the payload.
Now the balloon is inverted to it's flight orientation.
It's ready to fly, all I need to do now is let go!
And away she goes!
Into the wild blue yonder. (Is yonder even a real word?)
Click Here for a 2 1/2 minute video of the filling and launch.
Once the balloon was released, we watched it until it reached about 15,000' and we lost sight of it. I was spending my time watching the GPS data coming in. Everything depends on the GPS and radio system, if we lose data from the balloon, quite simply it's lost. As soon as we lost sight of the balloon, the chase was on! Bill drove and I worked the computer from the back seat while Vern tried the homing beacon receiver from the passenger seat. We really didn't need the homing beacon, the GPS data streamed in non stop, with the position indicator drawing the flight path on the map overlay. It was too easy, the only thing we had to be careful about was driving directly under the balloon. The radio antenna has a null area directly above and below, so it's better to stay a few miles behind the balloon for best signal. The only time I lost signal lock was after the balloon exceeded 45,000' and we were right under it. After we backed off a couple miles, we never lost the signal again.
As we tracked the balloon, I started getting nervous. The balloon was headed right for an area Vern and I had discussed earlier in the morning. It's an area of a river valley, and there are no roads for 8 square miles. Just about then, at about 65,000' I noticed the altitude started dropping. The balloon had burst, and the winds were taking it right into the one area we didn't want it to go!
We drove to the road closest to the area we suspected it would land, and parked on a small hill top. Bill got out and waved the tracking beacon receiver back and forth. I watched the computer carefully as the balloon dropped from 15,000' towards the earth. I told Bill he should be getting a good signal at that range, which was about 4 miles out and 3 up from us. He was getting a signal, but from some reason rather than the ping, ping, ping it should be, it was a continuos tone. The elevation at the landing site should have been in the 1,350' to 1,400' range. I was curious to see when I'd lose the GPS signal, the lower the altitude of the last signal I received, the easier it would be to find the payload. Much to my pleasure, the last reported position was at about 1,380'. Which meant the actual landing site should be very close to the last reported position.
We checked the map, and found we would have to drive a few miles out of our way, as the balloon had landed on the other side of the river, and (of course) in the area with no roads. Once we closed within 3 miles of the suspected landing site, more good news. I once again picked up he GPS signal and now had the exact coordinates of the payload! It didn't seem too bad, the payload was about 1/2 mile from a dead end road. So I headed out with the beacon receiver in one hand and a GPS in the other, Bill was following with the camera. After crossing a couple of small streams, several cattle fences and more hills than I care to recall, I caught sight of the payload in a small valley. I looked behind me for Bill, but he wasn't to be seen. So I went on to the payload. Other than a young calf checking it out, it was sitting there just like I had walked over and gently laid it there. Upright, with the parachute to one side and a lot of balloon remains on the other side. And of course, again, it was only about 50' from a small stream. Me and water....
Not sure where Bill was off to, I called him on the cell phone. He had turned back, and said he'd pick me up on a road to the South, which he thought would be an easier path to get out of there. What it was, was two more streams to cross and even bigger hills to climb. But I made it out in short order, probably smiling the whole time too.
Once we got home, I opened the payload. The first thing I checked was the video camera. First bit of discouraging news of the day, the camcorder had only recorded 41 seconds, not even recording the lift off. My guess is the battery lost contact and stopped the recorder. Odd, because I had checked that by shaking the camera and banging it in my hand, and never had a problem. Next I checked the still camera, I was pleased to find the memory card with over 200 pictures.
Ok, so here's what you want to see. The pictures... These are some of the better ones, a lot of them are repetitive so there's no sense in posting all of them. Click on a thumbnail to see a larger image.
Moving into the lower layer of clouds.
Above the first cloud layer.
Moving into the second layer of clouds
Into the next cloud layer.
Above all the cloud now.
Starting down now. Notice we are still above the two jet contrails.
Moving back into the upper clouds.
Coming out of the lower clouds. Notice the piece of balloon in the lower left.
Most of the lower descent was blocked by the burst balloon.
Almost back on terra firma.
Here's the chute, payload and balloon remains loaded up.
All in all, I'd say I was pretty pleased with my first high altitude balloon flight. Some of the pictures I got back are just great, just what I'd hoped for. I suppose next time I'll have to splurge for a new balloon. Although I could have reached a higher altitude with this balloon had I opted for a slower ascent and less free lift. I haven't calculated the ascent rate, but it was well over 1,000' per minute.
A few of the technical details:
Lift Off: 6:56 am
Time from launch to Burst: 48 minutes 32 seconds
Altitude at Burst: 63,966.1' MSL 62,586.1 AGL
Average Ascent Rate: 1,289.53 feet per minute
Distance from Launch Site to Landing Site: 22.4 Miles
Descent Time: 50:33
Average Descent Rate: 1,239 feet per minute
Total Flight Time: 1:39:05
Here's a screen capture showing the flight path in green. Disregard the horizontal green line, it was a momentary anomaly.
On this graphic I zoomed in, you can see the scale in yards on the map. Notice how the payload is swinging slowly under the balloon, even making small loops that the GPS recorded. Once the balloon burst the swinging stopped.
One thing I pondered for a while was how to attach the parachute to the payload string. I've seen people just dangle the chute over the side of the payload, but I was a little concerned the chute would open on the way up and slow the ascent. Where a chute attached at the apex to the payload string would stay closed on the way up, and open instantly after the balloon popped. I ended up using a large X-form parachute and attaching it at the apex of the chute. It worked fine that way, but the chute was a little oversized. It actually came down slower than it went up. Not that that's a problem, it gave us plenty of time to get under it once we knew it was coming down, but it does cause more drift and a longer distance to recover.
I think I'll go ahead and fly the other similar balloon I already have for my second flight. I won't use a cut down device this time to save weight, since I'm pretty certain the balloon will burst on it's own. I'll also replace the camcorder with a smaller digital video recorder. While it won't capture the entire flight, it should easily get all of the ascent and save another 1.5 pounds of payload weight. I'll go with a smaller chute, that will save some weight, and bring it down faster too. Lastly, I'll fill to a much lower volume. I think I can get by with about 2.5 or 3 pounds of free lift, coupled with a lower payload weight, that should give me a significantly higher peak altitude. Hopefully in the 80,000'+ range.