Chief Scientist -- Marks
Doppler Scientist -- Dodge
Doppler Operator -- Landsea
Cloud Physics Scientist -- R. Black
Observers -- Murillo (FSU), Guertin (PSU)
This document is divided into 3 sections (Each section is written by the Chief Scientist):
A secondary purpose for the mission is to continue testing the PMS probe orientation and location measurements begun last season by R. Black. These measurements are designed to determine the effect of the airflow around the wing on the microphysics sampling. A tertiary purpose is to test the instrumentation (radar system, dropsonde, field mills, etc.) on N43RF prior to any field program deployments.
The mission plan calls for N43RF to depart from Opa Locka around 1730 UTC and ferry to the W coast of Florida to coordinate patterns with Paul Willis in the van via cellphone. Paul will contact us when he is in position, approximately 1815 UTC. After attempting to fly a coordinated mission with the van, N43RF will pick targets of opportunity. Maximum mission duration will be <5 h.
Return to Top
As we were loitering over Florida Bay we noticed that the convective precipitation system we had just sampled continued to regenerate as it moved SE toward the disdrometer at the Agricultural Test Station. By 2000 UTC the precipitation system was nearly over the disdrometer location (25.39°N, 80.68°W). Hence, a pattern was set up to sample the system once again as it passed over the disdrometer. The first leg was at 10000 ft on a SSE track passing a few mile E of the disdrometer location starting at 2012 UTC. The tail radar was in perpendicular scan mode on this traverse. The traverse was followed at 2018 UTC by an attempt to box the system, starting to the W of the feature, with the tail radar in F/AST mode. Plenty of CG lightning was noted around the system. We completed the box with another 10000 ft leg NNW-SSE through the convective system starting at 2029 UTC (25.61°N, 80.58°W). After completing the box, we made a spiral descent to 1500 ft (shortly after reaching 1500 ft ATC requested we return to 2000 ft for the duration of our penetrations). We then proceeded to make four roughly N-S passes through the convective system over the disdrometer site with the tail radar in F/AST mode. The first pass we skirted W (upwind) of the heavy precipitation core sitting over the disdrometer site, passing roughly 3 nm W of the disdrometer. The second and third passes we went right over the disdrometer in precipitation (we could see the Agricultural Test Site buildings in the rain both times), passing overhead at 2049 and 2054 UTC, respectively. The last leg starting at 2101 UTC passed roughly 2 nm E of the disdrometer which was no longer in the heavy core. We noted a lot of CG lightning on the last three legs. At the end of the fourth 2000 ft leg, we climbed back up to 10000 ft at 2104 UTC, did a final true airspeed calibration over Florida Bay S of the convective system, and then returned to Opa Locka at 2144 UTC.
Return to Top
We recorded FAST (40 Hz), as well as, SLOW (1 Hz) data records from the main aircraft data system. Both record types are stored on a single DAT. We also recorded 2 DATs with radar data (one before and one after the system crash), and 1 DAT of cloud physics data. A box of ODWs (8 sondes) was baselined, with 2 sondes failing the PTH baseline. We left the sondes on the aircraft for future use. We also transmitted 1 min ASDL flight level data to test communications between the aircraft and NHC.
1. The radar data system went down twice during the mission. The first time, at the beginning of the mission, when the LF radar wouldn't transmit. Terry Lynch and Jim Roles replaced the LF R/T. The second time the radar system froze after the first set of convective penetrations and Peter Dodge restarted the system.
2. The 2D-P data seemed noisy with a lot of records with clear air updating. The 2D-C data seemed cleaner. R. Black will check the tapes to see how bad the problem is. The clear air updating will likely compromise the sample volume for rainfall estimation.
3. Communications with the Airphone was problematic. We could call Paul and he could call us. However, once a connection was made it was often broken or badly garbled. We need to try a cellphone the next time.
4. There are now four video cameras onboard N43RF (and likely also on N42RF). We need to start carrying 4 super VHS cassettes for each flight.
Return to Top