Flight 10: Released from Alamogordo, New Mexico, 0501 MST, July 5, 1947
Not recovered
This flight was the first to use a large plastic balloon as the lifting vehicle. The cell was spherical, 15 feet in diameter, and the walls were .008" polyethylene heat sealed at the seams (made by Harold A. Smith, Inc.). The altitude control was an automatic ballast valve, pressure-triggered to throw off liquid ballast. The equipment train used on this flight is shown in Figure 5.
[figure]
Figure 5: Train, Flight 10
The balloon rose to about 16,000 feet MSL and dropped back to 9000 feet MSL where it "floated" for at least 4 hours, at which time radiosonde reception failed. It is believed that the automatic ballast valve sealed off
-10-