31 May 2003 – Flight 803


Research Flight from OUN


Pilot: Tom Warner


T.O. 20:01 UT


T.D. 21:06 UT


Since the last flight, the sampling inlet tube for the NO analyzer has been bent over and tied down to the sampling mast on top of the canopy in an attempt to minimize the possibility of corona discharge.


A cell is noted ~40 nmi SW of KTLX making CG’s at 1740 UT. New cells keep forming, and each makes a few CG’s. At 18:50 UT thunder is heard at the airport. Very light precip can be seen falling from a cell to the S.  New cell development seems to be on the N side of the radar echo complex earlier, then switches to S side.


Tom reports cloud bases at 10.5 kft on climbout at 20:13 UT. Significant events noted by flight controller are:


20:16:56 – 20:17:33 – NO test


20:23 – 20:27 – 1st pass eastward at 16 kft. Estimate bases at 12 kft.


Then head southward toward new development.


20:30:29 - :47 – NO test in clear air


20:34 – 20:36 – Southward pass through newer storm. On exit, did a tight 180o turn then headed back through to the N


20:37 – 20:39 – 2nd pass, then out on north side. Turns 180o then goes back through to south, changing course slightly toward southeast and running through an elongated reflectivity maximum.


Reverses course and goes back through toward the north, exiting cloud at 20:45


Reverses course and goes back through toward south.


Reverses course and goes back through to north.


20:50:30 – Lightning strike to propeller.


20:53 – Pick up a course for Norman to return to base and check propeller.


The DMT element used on this flight had a thicker epoxy coating. Tests on the calibration mixture in the Tedlar bag after the flight showed a concentration of only 9 ppbv. There must have been a leak or some irregularity in the dilution process used when filling the bag.