You can view the track of the launch at aprs.fi.
While preparing the electronics pod for launch the LabQuest did not recognize the pressure sensor and one of the temperature sensors was intermittent. Another LabQuest was got from inside but the problem was not fixed so we launched knowing that the pressure and one temperature sensor were not going to work. The balloon was released at 10:15am local time. Because of the mostly clear sky and the low winds aloft meaning the balloon didn't travel very far from the launch site we were able to see the balloon up to about 55,000ft.
The preperations for the launch were just like the last one but went much smoother. We layed the tarp out where we were planning on filling the balloon and placed the helium container next to the tarp. Before filling the balloon we made sure that all of the electronics were turned on and in working order. While the electronics were being taken care of we secured the pods to the 1200 gram balloon with duct tape and zip ties. At this time we also created a tether for the balloon. Once the electronics were ok'd we began filling the balloon. We filled the balloon with approx. 200 cubic ft of helium. This proved to be sufficient because the balloon was able to lift the weight of both pods with ease, and once released began to rise at a steady pace of 1000 ft per minute.
The highest recorded altitude was 90,846ft. This was about 3 miles south of Prescott.
When the balloon was at about 8,000ft. we spotted the parachute. We maintained a visual all the way down until it landed on the road in front of us. The balloon landed at 12:58pm local time for a total flight time of 2:43.
Parachute Diameter: 6 ft.
9 Lines were attached from the Parachute to the Wooden Ring, and 4 lines were attached from the Ring to the Box containing the tracking system. Strings did not tangle. The parachute landed well and in good condition.
Still photos were taken about every 10 seconds for the entire flight. The pictures are 640x480 and for most of the flight are very clear. On the descent when the balloon passed through the clouds at around 8,000ft. condensation formed on the lens and the remaining pictures were unusable.
Launch, Chase, and RecoveryEdit
The APRS functioned flawlessly from launch to landing. The Garmin GPS V worked to the maximum altitude of 90,846ft. The chase team was able to receive packets directly from the balloon for the entire flight. Amateur stations also received the balloon directly for the entire flight. The antenna had been slightly bent from the previous launch but when it landed on the road it was severally bent, even bending the sma plug that is attached to the transmitter. The last position sent to the Internet was at 2,146ft. which was about 700ft above the ground. While the transmitter survived the landing (we received more positions directly in the chase vehicle) packets from the ground did not reach the Internet.
The chase vehicle recorded the packets it received directly from the balloon in the kml format. Also in this same file is the position of the main and secondary (though with position only every 10 minutes) chase vehicles. This data only recorded time, position and altitude.
The cellular tracker worked much better than we predicted. The cell phone transmitted it's position from the ground to 20,000ft. perfectly. After ascending above 20,000ft. the phone continued to transmit it's position but saying it was at an altitude of 19,854ft. That worked up into 37,000ft (that altitude taken from the time the position was sent because it was still reporting 19,854ft.) when the phone stopped transmitting until it reached 46,000ft. where it kept sending correct position but still incorrect altitude. At 80,000 the phone stopped transmitting again until it was received at 20,000ft. on the way down. From this point to the ground it transmitted correct altitude. The phones last transmission was from the ground exactly where the balloon landed.
The SPOT also worked for the entire launch. When the electronics pod was being powered on the SPOT's position was received while it was upside down. It sent position every 10 minutes until an altitude of 40,000ft. On the way down a position was received at 33,000ft. The last position received from the SPOT was at 5,700ft. but when it landed we turned it off before it had the chance to send another position. Had we not found the balloon we believe that the SPOT would have sent a valid position from the ground.
Connected to the APRS transmitter was a Garmin GPS V. It is designed primarily for vehicle navigation and has the ability to record a track of where it has been. We configured it to save its position every second with the hope to have a more accurate track of the balloon than the 30 second position data from APRS. Unfortunately we didn't test the GPS in this configuration. During the flight it only recorded data up to about 3,000ft. When we recovered the balloon the GPS displayed Memory Full.
For this launch we had a Vernier LabQuest connected to four sensors (external temperature, internal temperature, barometric pressure, and relative humidity). On the ground when powering up the electronics pod the LabQuest would not recognize the barometric pressure sensors and one of the temperature sensors was being intermittently recognized. We tried a different LabQuest device but the same problem persisted. We decided to send up the LabQuest anyway with all four sensors plugged in. During the flight it only recorded data from the relative humidity sensor and one of the temperature sensors (we think it was the external temperature). The coldest recorded temperature was -65C which occurred around our maximum altitude. The sensor will not record any temperature below -65C and it recorded -65C for a 3.3 minutes around the time of bursting. Based on how the temperature was decreasing in the past few minutes we could extrapolate a maximum coldest temperature of around -75C if the temperature decreased linearly.