ER-2 Flight: 96106

Date: April 21, 1996

Mission: Cirrus and persistent contrails over ARM CART site.

Mission Objectives

Observe cirrus clouds of various ages and contrails in the presence of cirrus. In situ cloud sampling with the DC-8 with ground-based uplooking and ER-2 based downlooking characterization of cirrus and contrails. Investigate differences in the radiative signature of contrails and natural cirrus. Flight plans support combined ER-2 remote sensing and DC-8 in situ cloud microphysics studies.

Flight Summary

Take-off time was 1655 UTC and landing 2350 UTC. ER-2 flew 240 and 60 degree oriented lines (approximately 110 n mi long) over the ARM CART site (36 36.3'N 97 29.1'W) in coordination with the DC-8. ER-2 was at the CART site at 1815 UTC and the cirrus was moderate. On the 1823 to 1840 UTC the cirrus had thickened (could barely see the ground) and was extensive. During the later part of the cooridnated flight with the DC-8 the clouds over the ARM site began to break-up. DC-8 made vertical profiles of the clouds.

ER-2 ended coordinated pattern with the DC-8 at 2138 to overfly convection in vicinity of the ARM site. Convective overflights were of mature storms except the last leg when he flew over a storm that was just beginning to have cirrus blow-off. Location and times of thunderstorm runs were 36:09N 97:46W (2138 UTC) to 38:00N 94:19W (2207 UTC); 38:0N 94:10W (2213 UTC) to 37:55 N 90:45 (2225 UTC) to 36:42N 96:13W (2237 UTC) to 36:00N 97:27W (2248 UTC) to 35:48N 98:17W (2253 UTC) to 37:37N 97:00W.

Highlights

Lots of cirrus and contrails (including that of the DC-8) reported by ground observes at the ARM CART site. Overflew extended contrail toward end of coordinated runs with the DC-8. Overflew cold convective tops with the HIS and MIR. Many passes over the ARM CART.

CLS observed a pileus cloud during ER-2 runs over convection.

Instrument Status

• MODIS Airborne Simulator (MAS): Operated. Good data collected on first tape. At 2124 MAS stopped recording data on second tape.
• Cloud Aerosol Lidar System (CALS): Operated. Good data collected on first tape, problems recording on 2nd tape.
• High-Resolution Interferometer Sounder (HIS): Operated. Good data collected.
• Millimeter-wave Imaging Radiometer(MIR): Operated. Good data collected.
• Tilt Scan CCD Camera (TSCC): Operated. Camera shutter problems.
• Radiation Measuring System (RAMS): Operated. Good data collected.
• RC-10 Camera: Operated (black and white visible film- 6 inch lens) ran out of film at 2118.

Additional Pilot Notes: ER-2 made a contrail on ascent.Commercial aircraft contrail at 1812 UTC. During legs between 2045-2103 and 2109-2129 the ER-2 flew over the DC-8 traveling in the opposite direction. Followed a long contrail (50-100 n. mi) during the 2109-2129 UTC leg. Circle rings of DC-8 spiral run near the end of the coordinated segment were visible from the ER-2. While over mature storms did have an "elevator ride" but not too much deviation in altitude. Reports of thunderstorm tops near 57K feet were consistent with pilot's observations. Growing cell had about 45 K feet.