CAMEX aircraft make test runs

CAMEX-3 status report

August 14, 1998: (This is the third in a series of stories covering the ongoing CAMEX mission to hunt hurricane data in a way not done since the 50s. Other stories are linked in below.)

Three of the aircraft involved in the third Convection and Moisture Experiment (CAMEX-3) probed through and above thunderstorms and anvil-shaped clouds in a five-hour test mission Thursday afternoon.

The mission also served as the first scientific flight for studying tropical storms in conjunction with overflights of the Tropical Rainfall Measurement Mission (TRMM) satellite in the Texas-Florida Underflight campaign (TEFLUN). The TEFLUN-B ground coordination flight seems to be a large success. All three aircraft flew in stacked formation, on coordinated lines, through an active storm, instruments working well, with an overpass by TRMM.

The primary goal for Thursday was to sample a convective precipitation system - a thunderstorm - with all three aircraft within a 90-km (54-mi) range of the S-POL radar site located near Vero Beach, Florida at 27 degrees, 53.4 minutes N and 80 degrees, 44.7 minutes W. A second goal of the mission was to fly the NAST-I and the Lidar Atmospheric Sensing Experiment (LASE) over the ground instrumentation site located at Andros Island, Bahamas, to collect water vapor calibration measurements. Additional goals of the missions were to test the aircraft to ground communications and to calibrate the DC-8's Meteorological Measurement System (MMS) and the Polarimetric Scanning Radiometer (PSR).

The aircraft flew through and above thunderstorms in the near Atlantic to "check out" the suite of scientific instruments which will be used to study named Tropical Storms and Hurricanes during the study period which lasts through Sept. 23. The DC-8, a heavily converted commercial jetliner, took a spiraling flight path down the Florida coastline gaining altitude to 39,000 feet before heading Southeast over the Atlantic Ocean. The ER-2, a converted U2 spy plane, took a more direct route to a pre-selected rendezvous point.

Left, Above: A NASA map shows the ground track of the Tropical Rainfall Measuring Mission (TRMM) satellite and the fields of view of its instruments at the time of Thursday's aircraft calibration flights. (links to 640x512-pixel GIF.)

The ER-2, piloted by Bill Collette, and DC-8, piloted by former astronaut Gordon Fullerton and Dick Ewens, launched at 1900 UTC (3 p.m. EDT) which was an hour delay from the originally scheduled takeoff time due to the slow development of convection within range of S-POL.

After takeoff, the aircraft lingered in the Vero Beach area to allow LASE and other instruments time to warm up to proper operating conditions before beginning the Andros Island sortie. The ER-2 flew over a developing convective cell south of the Vero Beach during the waiting period. Each aircraft flew two flight lines that were 5 km (3 mi) off shore and parallel to the eastern rim of the island. The two aircraft were then directed to an area north of Titusville where an area of convection was developing. The University of North Dakota Citation launched at approximately 2115 UTC (5:15 pm EDT) to join the ER-2 and DC-8 in probing the thunderstorms.

The three aircraft were directed by the S-POL scientist to fly primarily east-west legs through the trailing stratiform rain region between the intersection of a convective outflow boundary and a sea breeze gust front. The overall mission accomplished its stated goals and was considered a success.

Daily Mission Scientist: Ed Zipser
Deputy Daily Mission Scientist: Gerry Heymsfield
DC-8 Scientist: Ed Zipser
S-POL Scientist: Gerry Heymsfield
Patrick Scientist: Robbie Hood
Water Vapor Scientist: Harvey Melfi
Nowcasters: Bart Geerts and Richard Wohlman

Note: More details are available in the NASA press release describing CAMEX-3. Check back as hurricane season progresses. We will post science updates as the campaign develops. PIX: High resolution scans of 35mm camera photos from the CAMEX-3 campaign are available from Public Affairs Office at NASA headquarters. Please call the NASA Headquarters Photo Department at 202-358-1900, or contact Bill Ingalls at bingalls@hq.nasa.gov. CAMEX Series Headlines August 12: Overview CAMEX story , describes the program in detail. August 13: CAMEX maiden flight , for calibration of TRMM satellite instruments August 14: CAMEX test flights , CAMEX flies over tropical storm weather in successful calibration run (this story) August 18: CAMEX aircraft make second flight with TRMM , second calibration run for TRMM August 20: CAMEX may get first chance at a tropical storm , later this week  August 21: Here comes Bonnie! , CAMEX scheduled to fly over T.S. Bonnie  August 22: West by Northwest , CAMEX team may have to evacuate to Georgia  August 24: Eye-to-eye, and Bonnie winks, CAMEX team makes first flight through eye  August 25: Snow in August, Bonnie surprises the hurricane team  August 26: Camera of many colors Hurricane hunters using advanced scanner to peer into storms August 28: Preparing for Danielle NASA team takes break as Bonnie fades away August 31: Quite a Windfall Hurricane team completes first half of unique science campaign September 2: Bonnie Cuts a Towering Figure Satellite radar shows mountainous cloud chimney September 4: Hurricane team studies Earl Four aircraft probe storm September 10: NASA team awaits next hurricane September 16: Hurricane season passing its prime Thunderstorm studies continue as a new hurricane candidate wends its way from Africa. September 18: Two new storms brewing for hurricane research team Scientists fly 4 out of 5 days, clear air sampled over the Bahamas, oceanic convection data collected east of Cape Canaveral September 21:The last hurricane - CAMEX team wrapping up campaign with flights into Georges September 23: Hurricane Georges puts on a light show - CAMEX team treated to purple sprites and weird lightning NCAR has an extensive writeup on the GPS dropsondes used in CAMEX-3 and other atmospheric campaigns. A new study - not related to CAMEX-3 - by the Arizona State University suggests a link between hurricanes in the northwest Atlantic and air pollution.

CAMEX-3 is an interagency project to measure hurricane dynamics at high altitude. From this, scientists hope to understand better how hurricanes are powered and to improve the tools they use to predict hurricane intensity.

An overview story (Aug. 12, 1998) describes the program in detail. The study is part of NASA's Earth Science enterprise to better understand the total Earth system and the effects of natural and human-induced changes on the global environment.

Web Links CAMEX-3 home page contains links to daily flight operations and instrument descriptions. Lightning Imaging Sensor aboard the TRMM satellite observes lightning from above the clouds - and my lead to better warnings on the ground. MACAWS uses the Doppler effect (red and blue shifts) to measure wind velocity. SPARCLE is a Space Shuttle experiment set for 2001 to demonstrate laser wind measurement from space.

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