DC-8 Mission Science Report

This DC-8 mission was designed to fly east from JAX NAS and then south to Ocean Buoy 41009 at 28.5 N, 80.2 W. Next, a Figure 4 would be performed over the buoy with 50 nmi legs before heading east to Ocean Buoy 41010 at 28.9 N, 78.5 W where another Figure 4 with 50 nmi legs would be performed. A dropsonde release was scheduled at the second buoy. North of the second buoy, the aircraft was scheduled to head due west for MMS manuevers and then head north for the return to JAX NAS.

A flight over the ocean was planned to aid the calibration of the PR-2, verify the DC-8 dropsonde data transfer to the NOAA Data Pipeline, monitor the performance of the CVI during cloud sampling, and to sample ocean winds using C-STAR.

Takeoff occurred as scheduled. Seventeen minutes into the flight, the PR-2 experienced problems with the 35 GHz channel. The pattern over the first buoy was flown as planned to the allow the PR-2 team the opportunity to reset the instrument. Unfortunately, the 35 GHz channel would not stay up for more than a few seconds. The Mission Scientist decided to shorten the mission plan by not flying to the second buoy since testing PR-2 was the primary objective of the mission. A request was made to ATC to release a dropsonde on the eastward course to the second buoy. However due to heavy commerical air traffic in the area, the DC-8 was put in a holding pattern for several minutes before permission was granted. The dropsonde was released at 1654 UTC over 28.7 N, 79.8 W. Splashdown occurred at 1706 UTC. Positioning for the MMS calibration manuevers were attempted next, but this hampered the success of the dropsonde TEMP DROP data transfer. A successful dropsonde TEMP DROP was accomplished once the aircraft was leveled off for several minutes. (For the future, the Mission Scientist should remember that the dropsonde system needs the aircraft to fly in a level position for several minutes for proper data collection and data broadcast.) The DC-8 was flown through a small stacked cumulus at about 8500 ft. and then again at about 5000 ft. to validate performance of the microphysical instrumentation. The aircraft then returned to JAX NAS for landing.

The ground assets at Andros Island and in the Florida Keys maintained a normal operational schedule. The Aerosonde completed a mission this morning that began yesterday afternoon.