29 July 2003 – Flight 819

Research Flight from GXY

Pilot: Charlie Summers

T.O. 19:17 UT

T.D. 20:20 UT

Weather pattern continues to hold. Convection develops on all sides of CHILL by early afternoon. Some suggestion of a frontal boundary extending northeastward to Kimball and even further.

After take-off, the first target was to the east. Several passes were made at the 18 kft level. Lightning was as frequent as every 15 s, and some soft hail was reported. After this storm began to collapse, a new target to the south was selected. One pass to the south was made through this storm after which the generator failed and the mission was terminated. The data system was turned off at 20:08 while still airborne in order to conserve power.

The hydrometeor image data look good. Peak updrafts were ~10 m s^-1 and peak cloud liquid water concentrations were  ~2 g m^-3. Updrafts tended to be on the north sides of cells.  The NO test produced only a 10 ppbv reading although the concentration was expected to be 50 ppbv. We suspect a hole in the bag carrying the calibration gas mixture.