ER-2 Flight: 99054

Date: March 21, 1999

Mission: NPOESS EDR and moisture mapping, night cloud detection, snowfall detection, HSRL comparisons.

Mission Objectives

Assess NAST-Interferometer performance in detecting moisture gradients and structure in cold airmass by flying over mid tropospheric dry slot over WI.  Validation provided by INL, GRB and MSP radiosonde launches (00 UTC launch).  Snow detection (NAST-M) by overflying Lake effect snowshowers along eastern shore of L. Michigan. Comparisons to uplooking AERI measurements at Truax Field. Compare MAS and HSRL collocated measurements of cloud over SSEC for optical depth and Re retrieval (night only) if clouds are present..

Flight Summary

Take-off was at 2200 UTC. ER-2 landed at 0245 UTC (99081).

ER-2 spiraled up from Truax and flew to GRB, where it flew eastward at altitude to Cheboygan, MI and picked up a southwestward track taking it along eastern shore of L. Michigan.  Some snow showers present along shoreline at that time, most intense near Traverse City (2300 UTC).  Only low cloud, bkn at times.  Sky light level is low (23 UTC), emulating night conditions.  Racetrack pattern (western leg coordinates are 43:06, 88:17 to 46:13, 91:41; eastern leg is offset by 30km) traveled twice around, with mostly clear conditions (few cu in SE WI).  Traversed mid tropospheric dry slot oriented N-S down centerline of WI.  Racetrack is oriented with upper level winds as planned.  NAST-I failed near end of first line of racetrack.  Mission finished by overflying MSN in clear conditions at about 0215 UTC.  HSRL and AERI operated throughout the flight.  Surface is bare ground over most of WI.  No classondes at AERIbago due to hardware failure.


Snowshowers on eastern shore of L. Michigan.  BKN and OVC low cloud in low light conditions.  Two orbits of racetrack pattern over mid tropospheric dry slot.  Overpass of SSEC (HSRL, AERI on roof, AERIbago were operating).

Instrument Status

Additional Pilot Notes: Pilots continue to report brown haze in atmosphere