Saturday, 3 June

T-28 Flight 751

Project Flight 6

Take Off ~ 23:42 GMT

Return to Base: 01:05 GMT

Pilot: Tom Warner

 

The aircraft was launched toward a target storm ~50 mi northeast of CHILL. The storm had weak multicellular structure. Six passes were made through the complex on mostly east-west trajectories. There was good coordination with the mobile mesonet and electrical ballooning efforts. Two balloons were launched during the T-28 mission, one of which was noted by the T-28 pilot at 23:55 UTC in clear air as it rose through the aircraft altitude. By the end of the mission, the storm was decaying visually as well as on project radars.

 

The pilot reported seeing several lightning flashes. The E_z electric field component switched sign quickly, perhaps due to the lightning flashes, along some parts of the flight, over distances of 2 to 3 km.    In other parts, the E_z component stayed positive or negative for distances up to 20 km, apparently due to extensive regions of unipolar charge distribution within the cloud.   The peak E_z field component was as strong as 30 kV/m.

 

There were two updraft regions: one strong and one weak, separated by about 20 km, the north updraft region being about 80 km north and 80 km east of the CSU-CHILL radar site.

 

The HVPS recorded about 7 minutes of particle images and charges in the early part of the flight. Both positively and negatively charged particles were encountered in the same cloud regions.

 

The storm produced no CG’s observed by surface observers or by the NLDN. Observers did report active intracloud lightning. Hail up to one inch was reported from the storm prior to the mission, but no hail was observed at the ground during the mission.

 

The data system clock was 2 min 15 sec behind the correct time. The clock on the video recorder was set correctly. Data were of generally good quality, except for the HVPS, from which image and charge data were obtained only on the first pass.  Hail spectrometer images were obtained, but not concentrations and automated sizing information. Precipitation particle concentrations were low. Convective cores, containing elevated cloud liquid water concentration, were small.