Our launch was a huge success. We surpassed our goal of 85,000 feet. We were able to reach 104,685 feet. The balloon ended up popping over H35 North and came down in a little town named Danbury, WI. The students were able to find the balloon hung up in a scrub oak tree about 60 feet off the ground.
Our completed payload came in at 2.1 pounds. Using these calculations, we ended up filling a 2L pop bottle with 3 pounds of sand to give ourselves roughly one pound of free lift. We under estimated the free lift a little as we were trying to get as high as we possibility could. We ended up placing 3 hand warmers into the payload in an attempted to keep the batteries warm. At one point we got an internal payload temp reading at 46C which converts to 114.8 degrees F. One of our students came to the conclusion that this high temp may have been responsible for our camera failure at 28,607 feet. We know this altitude by looking at the last time the camera took a picture and comparing that time to the beacons that were coming back from the RTrak-HAB.
The students operated as a well orchestrated team. We meet in Mr. Olson's room prior to the launch and each and every student had a role to fill. We let the public come in to the room prior to launch and visit with the students and get a guided tour of all the equipment needed to experience a successful flight. Once on the flight deck, we had Rachel and Travis talk to the public and explain each step as we completed them. They did a wonderful job keeping the public in the know as to what was happening as we prepared the equipment for flight.
All in all the launch was a huge success. We managed to launch a balloon and get it back in one piece. The only problem we encountered was our camera decided to shut off at 27,500 feet. Everything was working perfectly up to that point. We are not sure why the camera did this. In every test run we made, the camera worked flawlessly and ran for about 2.5 hours on a battery charge. We will be trouble shooting this over the next moth or so and try to figure out what happened. Next time we will run two cameras so we have some sort of backup.
The payload ended up coming down in Dansbury, WI, about 10 miles east of the St. Croix River valley. You can see the flight path in the picture. The total flight was about 135 miles as the crow flies. We were concerned about the balloon popping over Mille Lacs Lake and coming down in the lake but as it passed over the lake the balloon was only at 27,000 feet. We averaged about 500f/m of ascent. Had our camera not failed, we would have been rewarded with some beautiful pictures given the fact our payload hung out between 75,000-104,685 feet for about 20 minutes! Next time!
After the balloon popped, the last known altitude put the payload at 5,800 feet. We did not hear back from the tracker after that. This made us a little concerned. But, we had sent the PocketFinder along to help in this. We figured we might lose the tracker once it touched down since the likely hood of landing in a heavily wood area ws high. So, we ended up bringing up the PocketFInder app on our iPhones and told the PocketFinder to go into tracking mode. The PocketFinder should itself immediately on a Google map. We were able to drive right to it's location and find the payload up over a hill lodged up in a 60 foot scrub oak tree.
The RTrak-HAB worked like a charm. We had it beacon it's location every minute. We tracked those beacons in the chase car using an iPad and a few iPhones. That set up worked well. Here is our best picture taken at 27,500 feet right before the camera decided to shut down. We are going to launch another payload using the same 600g balloon toward the end of April. This time we are going to design a paylaod with two seperate cameras. They will each be pointing a different direction. Attached to that will be a seperate payload with the RTrak-HAB and the PocketFinder.
You can also download an excel spreadsheet file that has all the data of the flight for those that are interested in the technical aspects of the whole flight.
Here is a kml file you can download and place into Google Earth to show the complete flight.
Here is an excel file that shows all the data from the flight. It is interesting to look at. It shows the ascent values, the beacon times, the descent values and other interesting data.
Here is another excel file that shows height in meters and the longitude and latitude.