16 April 1995

Vortex NOAA Aircraft Mission #3

Flight ID:

950416I

Flight Track:


Click image for full resolution.

Flight Crew:

Chief Scientist: Watson/Ziegler         Flight Director:  Damiano
Doppler Radar:   Shepherd               Pilots:           Kennedy/Tenneson
Cloud Physics:   ---                    Data Technician:  Pradas
Radiometer:      Fedor                  Systems Engineer: Lynch/McNamara
Observer:        Shapiro
Observer:        Atkins
Observer:        Ching

Takeoff Time: 1857 UTC                  Landing Time: 0049 UTC
Official Mission Duration: 6.1 hrs
Mission Breakdown VORTEX: 6.1 hrs       ARM: 0.0 hrs
Number of Data Tapes Used:  Radar: 4    Cloud Physics: 1        Video: 3


Data Systems Log

Radar Data System Log   Time On(UTC)    Time Off(UTC)   Comments
Tape #1                 1919                            Start LF&TA
                                                        TA velocity
                                                        problems
                                        2110            Radar down
Tape #2                 2117                            No Velocity on TA
                        2224                            TA velocity up
                                                        Bad cables
                                        0024            Stop record
Notes: It seems that a cable may be the problem


Cloud Physics Log       Time On(UTC)    Time Off(UTC)   Comments
                        1800            0000

ETL Radiometer Log      Time On (UTC)   Time Off (UTC)  Comments
                        1855            0052            No problems

Summary:

Tall Tower Mode

Ample moisture, good shear, and a weak northerly surge in western Oklahoma suggested possible supercell development somewhere in the western part of the state. The ground intercept teams departed for northwest OK only to decide to go south and west when a supercell was reported in far southwestern Oklahoma.
The P-3 departed OKC at 1857 UTC climbing to FL100 encountering weak convection near Watonga, OK. While the ground teams re-deployed southward, the P-3 provided radio repeater service, since the teams were scattered across tens of miles. The P-3 woes with respect to the tail radar velocities had not dissappeared as expected. Terry Lynch and Richard McNamara spent the next 6 hours testing one hypothesis after another to determine the cause.
Their conclusion was that cables were the culprit. New cables will not arrive from Tampa for several days.
We finally reached the convective activity in southwest Oklahoma by 2030 UTC observing multiple cells along the frontal boundary. Several BWERs were observed. After several unconfortable rides we descended to 3000 AGL below the clouds at 2200 UTC. Intermittently good velocity data began at 2224 UTC. By 2300 UTC, most of the convective activity was decreasing in intensity with the FC cancelling operations at 2350 UTC.
Another null case consuming 6.1 flight hours.

Irv Watson

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