Chief Scientist: Watson/Ziegler Flight Director: Damiano Doppler Radar: Shepherd Pilots: Tenneson/Kennedy Cloud Physics: --- Data Technician: Pradas Radiometer: Fedor Systems Engineer: Lynch Observer: Nadler Observer: Parrish Takeoff Time: 1903 UTC Landing Time: 0047 UTC Official Mission Duration: 6.0 hrs Mission Breakdown VORTEX: 6.0 hrs ARM: 0.0 hrs Number of Data Tapes Used: Radar: 1 Cloud Physics: 0 Video: 3
Data Systems Log
Radar Data System Log Time On(UTC) Time Off(UTC) Comments Tape #1 2112 Start LF 2250 Start TA 2320 Stop record Notes: Velocity heavily speckled, receiver replaced at 0000 UTC Cloud Physics Log Time On(UTC) Time Off(UTC) Comments No Data Collected ETL Radiometer Log Time On (UTC) Time Off (UTC) Comments 1831 No problems
The proposed flight plan was to setup a rectangular box pattern, initially at 1000'AGL, at the intersection of the cold front and dryline boundaries. The pre-convective box pattern should be maintained until convection develops.
We arrived at Duncan, OK at 1923 UTC at 1000' AGL. A basic box was initiated with predominantly 5 minute legs between Duncan and Ratliff City centered on the cumulus line. Winds were southerly SE of the cloud field and northerly NW of the cloud field. The first westernmost leg had westerly winds and lower dewpoints indicative of the dryline. Northerly flow gradually gave way to southerly flow over the next hour or so. Very hazy conditions were noted NW of the cloud field.
The FC gradually became weary of the region and ordered relocation eastward to near Sulphur, OK. We adjusted our box eastward from Ratliff City to near Sulphur, climbing above the cloud deck at 2050 for a better view. Upon noticing (2100 UTC) larger TCU to the north in the vicinity of Ada, we orientated our track for NE-SW legs on the SE side of the rapidly growing/decaying TCUs with tops reaching 15-20,000 ft.
By 2250 UTC, several cells had made it to Cs level. However, by 2345 UTC, the region had deteriorated. A tornado watch was issued at 2315 UTC, but was cancelled by 0300 UTC with no severe weather reported.
We were plagued by radar problems with velocities showing considerable speckling. The problem was solved by replacing the tail radar receiver.
Another null case consuming 6 flight hours.
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