ER-2 Flight: 96104

Date: April 16, 1996

Mission: Persistent contrails/cirrus over ARM CART Site.

Mission Objectives

Observe T-39 and DC-8 generated persistent contrails of various age. Contrail advection over CART site will be overflown by ER-2 for combined ground-based uplooking and ER-2 based downlooking characterization of contrails/cirrus. Characterize ambient radiometric conditions of atmosphere by flying upwind of T-39/DC-8 contrail generation region.

Flight Summary

ER-2 launch at 1700 UTC; ER-2 recovery at 2335 UTC. ER-2 flew 12 legs of an east-west oriented line (headings 90 and 270 degrees true north; 130 nm length) with ARM CART site (36 36.3'N 97 29.1'W) positioned 50 nm from western end of nadir flight line. Final 2 legs extended to 180nm for additional downwind coverage of old contrails. Total of 12 overpasses of ARM CART site. T-39 flying 10 nm diameter circles positioned 10, 20, and 30 nm upwind (west) of ARM CART site. DC-8 flying north-south oriented legs centered at 0, 10, 20, and 30 nm downwind of ARM CART site and then flying racetrack (oriented about 15 degrees off ER-2 heading). No time-dependent positioning coordination between ER-2 and DC-8 or T-39.

Cirrus in westerly flow aloft of varying thickness over ARM CART site and all along ER-2 flight line. T-39 contrails were not persistent. DC-8 contrails more persistent than T-39. ER-2 pilot had 2 visual observations of DC-8 contrail (1802 and 2009:30 UTC).

ARM CART site Central Facility coordinates verified for DC-8 and ER-2 flight plans.

Highlights

Lots of cirrus of varying thickness observed by ER-2. DC-8 with contrail apparent in MAS data at 1802 and 2009 UTC. ARM CART site uplooking lidar operatining during mission. Twelve overpasses of ARM CART site (approximately 1758, 1828, 1849, 1918, 1939, 2009, 2030, 2100, 2121, 2150, 2211, and 2154 UTC).

MIR detected cirrus.

Instrument Status

• Modis Airborne Simulator (MAS): Operated. Good data collected.
• Cloud Aerosol Lidar System (CALS): Operated. Good data collected
• High-Resolution Interferometer Sounder (HIS): Operated. Good data collected.
• Millimeter-wave Imaging Radiometer(MIR): Operated. Good data collected.
• Tilt Scan CCD Camera (TSCC): Operated in non-data collection mode.
• Radiation Measuring System (RAMS): Operated. Good data collected.
• RC-10 Camera: Operated on all but first flight leg (black and white visible film- 6 inch lens).

Additional Pilot Notes:. DC-8 contrail short-lived at 1802 UTC encounter. No visual of T-39 aircraft or contrails.