April 27, 1996

Mission Summary

DC-8 SUCCESS flight #209 [960207] (scientist: Brian Toon)

SUMMARY: This flight met its basic objectives. We did sample the T-39 contrail for a substantial period of time. Very small particles of ice were seen. There was some variation in the contail properties with our position in the contrail. We also did a successful profile of the clouds over the CART site. We did not make a persistent contrail in the satellite overpass period. Calibration of the instruments went fine.

Mission Objective

DC-8 TEST-FLIGHT

• sample the contrail of the T-39
• profile cirrus and midlevel clouds over the CART site
• make a contrail during the satellite (NOAA 14) overpass
• perform manuevers to calibrate MMS and the radiometers
• pass through wave-clouds over New Mexico (optional)

Flight Track

Flight Log

OPERATIONS
FLIGHT PLAN:
Take off is planned for 16.00 UTC (11.00 am local time).
The plan is to proceed to as high an alititude as possible with the DC-8 following the T-39. We will then follow the T-39 on race tracks for about 1 hr. The goal is to sample its exhaust and its contrail as well as to test the lidar. Then we will spiral down at less than 1000 ft/ min over the CART site and begin profiling the clouds. At about 19.20 UTC we will make three circles over the CART site so that we have made a contrail for a NOAA satellite overpass (19.47 UTC). We will then make a square box centered over the CART site to calibrate the radiometers and MTP. Then we will again spiral over the CART site and make a final profile of the clouds. If wave clouds are present we may break off to find them either after the T-39 and first spiral, or just after the satellite overpass.

TAKEOFF/LANDING
The DC-8 left Salina at 16.08 UTC (11.08 am local time) and returned to Salina at 21.30 UTC

FLIGHT REPORT
We flew the planned pattern over the CART site.

METEOROLOGY-REPORT
FORECAST: Meteorology expected: We expect that the tropopause will be relatively high over the CART site. Cirrus should be present sporadically as bands of moisture move through. There may be mid-lower level clouds also present over the CART site. There may be wave clouds over New Mexico.
OBSERVATIONS: Cirrus clouds were present over the CART site. However, we not able to make persistent contrails, and did not observe many contrails from other aircraft. Middle level clouds moved away during the day leaving some low level fair weather cumulus and a high level thin cirrus toward the end of the flight.

INSTRUMENT STATUS
All of the instruments are functional, except the Lawson probe. We will fly the 2DC-probe, the cloud scope, the VIPS and the the MASP on the pylons.

• BALLENTHIN: Instrument apparently failed due to a vacuum leak.
• BAUMGARDNER: Worked fine.
• BRUNE: Worked fine.
• CHAN: Worked fine.
• COGGIOLA: Problem with CCN/IN counter.
• COOPER: Worked fine.
• DADS: Worked fine.
• FERRY: Worked fine.
• GARY: Worked fine.
• GERBER: Worked fine.
• HAGEN: Worked fine.
• HALLET: Worked fine.
• HEYMSFIELD: Worked fine, but VIPs failed.
• HUDSON: Worked fine.
• LAWSON: not available
• RODGERS: Worked fine.
• SACHSE: Worked fine.
• TALBOT: Worked fine.
• TWOHY: Worked fine.
• UTHE: Worked fine.
• VALERO: Worked fine.
• WEINHEIMER: Worked fine.

Mission Highlights

• T-39 contrail particles were too small (less than a few microns) to be seen on the cloud scope (Hallett)
• possible regions of new particle formations (Hudson, Rodgers)