Microphysical Data from UND Citation Aircraft

Characteristics

The data is very preliminary, before using this data in your publication, please contact the Principal Investigator Dr. Jeffrey Stith (stith@aero.und.edu).
The details of the flights and instrument performance as provided by the PI are given here.

Table 2.    UND Citation Instrument Status

Date	INS	GPS	Video	Liq. H2O	FSSP	1D-P	2D-P	2D-C	CPI	HVPS
13 Aug 98		N	N			N	N			X
15 Aug 98							X			X
20 Aug 98	P						X		P	X
21 Aug 98						P	X	P	P	X
22 Aug 98										X
26 Aug 98			N				X			N
27 Aug 98							X		P
29 Aug 98							X
2 Sept 98  #1							X		P	N
2 Sept 98  #2							X			N
5 Sept 98							X		P	P
8 Sept 98							X	P		P
10 Sept 98				N			X	P		P
13 Sept 98							X
14 Sept 98  #1			N				X
14 Sept 98  #2							X
15 Sept 98  #1							X
15 Sept 98  #2							X

Legend:

	Normal Operation
P	Partial Data
N	No Data
X	Not Installed

Files Format

Column  Designator      Description             Units
1       Time            UTC                     Seconds From Midnight
2       A048            INS Latitude            degrees
3       A049            INS Longitude           degrees
4       A091            GPS Latitude            degrees
5       A092            GPS Longitude           degrees
6       A093            GPS Altitude            meters
7       A023            Pressure Altitude       meters
8       A004            True Air Speed          meters/second
9       A029            Air Temperature         C
11      A039            Liquid Water            gm/meter^3
12      A102            FSSP Liquid Water       gm/meter^3
13      A101            FSSP Concentration      #/cc
14      A140            Two-DC Concentration    #/liter
15      A126            One-DP Concentration    #/liter
16      A010            Wind Speed              meters/second
17      A012            Wind Direction          degrees
18      A053            Vertical Wind           meters/second

File Naming Convention

The names of the files are of the form:
UND.yymmdd.hhmmss.ascii,
where yymmdd is the date in year, month, day format and hhmmss is the start time of the flignt in hours, minutes, seconds format.

FTP Site

Points of Contact

Platform

Instruments

The three-dimensional wind field is derived from measurements of acceleration, pitch, roll and yaw combined with angles of attack and sideslip and indicated airspeed. The aircraft parameters are supplied by an LTN-76 inertial navigation system and a global positioning system (GPS). Strap-down accelerometers provide lateral and longitudinal aircraft accelerations. Turbulence intensity can be derived from differential pressure transducers and accelerometer outputs.

Cloud microphysical measurements are made with an array of Particle Measuring Systems probes ( FSSP, 1D-C, 2D-C, 1D-P) mounted on the wing-tip pylons.

• PMS Optical Array 1D-P for large partices
• PMS Optical Array 1D-C & 2D-C for cloud Particles
• Forward Scattering Spectrometer Probe (FSSP) for cloud droplet spectrum

These probes measure concentrations and sizes of particles from one micrometer to several millimeters in diameter.

In addition, HVPS probe is used to measure large volume of precipitation particles. There are probes to measure both liquid water content (J-W), and supercolled LWC/icing rate (Rosemounr Icing Rate Meter).

Cloud photography is accomplished with two side-looking and one down-looking 16 mm time-lapse cameras. A forward or side-looking video camera is also used to provide a visual record of flight conditions. A Bendix-King vertical profiling forward-looking weather radar can be viewed in the cockpit and recorded on video tape.

Data Acquisition and Display

Field Support