Instrument Development and Education in Airborne Science
J. Stith, et al.
NSF/NCAR C-130Q Hercules (N130AR)
Mission Results and Education Opportunites
Development of CO2 instrumentation Three modified non-dispersive infra-red CO2, based on Licor,
Inc. Sensors, were tested side-by-side and with similar calibrations
procedures. Several improvements were made to the CO2
instruments operated by the University of Colorado (CU), the University
of Wyoming (UWy) and NCAR, as a result of problems found during climb and
descents to/from high altitudes. UWy was able to complete their work by the
end of the third flight and CU completed theirs by the end of the project.
The NCAR instrument received several improvements and testing of it
continued with the October IDEAS project.
Aerosol Instrumentation Dave Rogers of RAF tested six different inlets for aerosols during
IDEAS, 3 during April and 3 in October. These flights were also used to
assess the performance of the RAF software for the Radial Differential
Mobility Analyzer. Two nepehelometers were added to the RAF aerosol
measuring rack in April. In October, an optical particle counter
and multi-channel analyzer was added along with a humidity system for
humidification of one of the nepehelometers. This aerosol system that
Rogers has integrated and tested provides a useful capability for future
aerosol measurements.
Remote sensing The EOL remote-sensing devices benefited from the extensive
testing opportunities provided in previous IDEAS flights. New channels
(wavelengths) on the Multichannel Cloud Radiometer (MCR) were installed and
tested and performed well. The Airborne Imaging Microwave Radiometer (AIMR)
had not been deployed for three years, so IDEAS provided an opportunity
to test aging components and replace them as necessary prior to future
requests. A downward-looking digital camera was installed and tested
for the first time during IDEAS I. All of these instruments were used
in concert to view vegetation and wildfire targets that had not been
extensively observed from the C-130Q previously.
Video Ice Particle Sampler (VIPS) A number of problems with the video camera and drive mechanism plagued
the VIPS, but by the end of April the instrument was performing well after
several modifications. This instrument was a major success for Heymsfield
in the Crystal project which took place following IDEAS.
Counterflow Virtual Impactor (CVI) The CVI had several problems with its disk drive system that proved
difficult to troubleshoot. By the end of April the problems were corrected,
and the improved instrument continued to perform well in the Crystal project
later that summer.
Evaluation of the Multiple Enclosure Device for Unfractionated
Sampling of Air (MEDUSA) The evaluation of the MEDUSA was completed in April.
Development of an airborne O2 Analyzer Several problems were encountered with this instrument in the pressure-
and flow-control systems. These were improved during the April missions,
however, the instrument was not able to perform as needed, and work
continued in the October IDEAS.
Continuous flow CCN counter Roberts (Scripps) tested a new continuous flow CCN counter. Several
difficult problems were found related to flow control, and they required
most of April to fix. However, the instrument was performing well at the
end of the month and was operated successfully during the Crystal project.
Improvements to the PMS 260X instrument This instrument was used in the Small Cumulus Experiment several years
ago to try to measure the concentration of giant aerosol particles that
might serve to initiate precipitation in warm clouds. (This was the first
use of this instrument for such low concentration measurements; it is
usually used for cloud measurements, where the concentration of particles
larger than 10 micrometers is much greater.) Unfortunately, after
publication of some results it was found that there was noise distributed
exponentially in magnitude, which mimics the natural aerosol spectrum and
invalidated the results. Testing of improved shielding for this instrument
was conducted in April, along with long-duration comparisons with other
aerosol instrumentation (to collect enough data to be statistically
significant for large particles). The improved shielding appears to
have solved the noise problem.
Improvements to the C-130Q One of the major complaints about the C-130Q was a lack of adequate
intercom stations for each person on the aircraft. In March, the RAF
rewired the system and added stations, so each seat has a dedicated
intercom station. This was tested successfully during the April program.
IDEAS and Education An instrumentation class from the University of Colorado at Boulder, led
by Professor Avallone, chose to participate in the April IDEAS flights. We
met with Prof. Avallone and discussed the class objectives and how her class
might benefit from this experience. The RAF conducted a half-day training
program for the students. It consisted of
The required safety briefing for flight on RAF aircraft,
A demonstration of RAF software for data processing and analysis,
A tour of the aircraft and instrumentation,
An introduction to the NCAR and University Scientists that were
participating in IDEAS, and
A discussion of the objectives of the class and how data from the
research flight might be used as a class project.
Students selected a mentor from among the IDEAS scientists and spent
time learning about the instrumentation from their mentor. They then
participated in one or more flights with their mentor and assisted in
collecting data. Following the flight(s) RAF staff and their mentor
assisted them in using the data for a class project. Students were able
to follow the flight schedule and data products/analysis from the IDEAS
web page, and they were encouraged to participate in submitting materials
for the rest of the participants. A number of class projects were based
on their IDEAS experience. Overall, the responses we have received from
students have been very positive.