ACE-ASIA Aircraft: C-130 Aircraft Flight Parameters; 1-sec rate (NCAR/RAF)
1.0 General Description
This dataset contains airborne measurements obtained from the NSF/NCAR
Research Aviation Facility (RAF) EC-130Q Hercules aircraft during the Asian
Pacific Regional Aerosol Characterization Experiment (ACE-Asia). This field
campaign was conducted out of Iwakuni, Japan from 30 March to 4 May 2001,
exclusive of ferry flights. This dataset contains only a subset of the
low-rate (LRT; 1 sample per second) production data. It does not include any
experimental or researcher data. The complete low-rate dataset currently
resides on the NCAR Mass Store in /RAF/2001/131/LRT/. It can be accessed
thru the Research Aviation Facility (RAF) web page at
http://www.atd.ucar.edu/rdp/mss_retrieval/.
High rate (HRT; 25 sps) data have not been processed at this time but
will be made available by RAF on a flight-by-flight basis. Processing and
distribution of these data will be made by RAF in response to individual
requests by project participants. These 1 Hz frequency data have been
processed and quality controlled by NCAR/RAF.
2.0 Detailed Data Description
This dataset contains data for 19 flights made during ACE-Asia. The
dates and times of each flight, along with the size of the complete (not
subsetted) dataset can be found in Table 2-1. This dataset contains only a
subset of the low-rate (LRT; 1 sample per second) production data. For a
list of variables included in this dataset see Table 2-2. Note that some
variables are different on different flights. For example, for liquid water
content (LWC) PLWCC1 is included for flights 10, 11, 12, 15, 16, 17, 18, 19.
PLWCC is included for flights 1,2, and XGLWC is included for flights 3
through 9, 13, 14. A list of these variables can be found at the end of
Table 2-2. The complete low-rate dataset currently resides on the NCAR Mass
Store in /RAF/2001/131/LRT/. It can be accessed thru the Research Aviation
Facility (RAF) web page at http://www.atd.ucar.edu/rdp/mss_retrieval/.
High rate (HRT; 25 sps) data have not been processed at this time but will
be made available by RAF on a flight-by-flight basis. Processing and
distribution of these data will be made by RAF in response to individual
requests by project participants.
RAF Bulletin No. 9, Appendix B (available on line at the URL:
http://raf.atd.ucar.edu/Bulletins/b9appdx_B.html#Time
has the following descriptions for time variables:
Raw Tape Time (h, m, s) - HOUR, MINUTE, SECOND
These three time variables are recorded directly from the aircraft's data
system.
Date (m, d, y) - MONTH, DAY, YEAR
These three variables represent the date when the aircraft's data system
began recording data. They are repeated as 1 sps variables but are NOT
incremented if the time rolls over to the next day. (Use base_time and
time_offset for reference timing.)
Reference Start Time (s) - base_time
This is the reference time for the netCDF output data files. It
represents the time of the first data record. Its format is Unix
time (elapsed seconds after 1 January 1970). Use this measurement and
time_offset to obtain the time for each data record.
Time Offset from Reference Start Time (s) - time_offset
This is the time offset from base_time of each data record used for
the netCDF output files. Since it starts at zero (0) and increments
each second, it can also be thought of as a record counter. Use this
measurement and base_time to obtain the time for each data record.
Complete documentation for the entire dataset can be found at
http://raf.atd.ucar.edu/Projects/ACE-ASIA/docsum.html.
This README has been linked to "Aircraft C-130 Aircraft Flight Parameters;
documentation (NCAR/RAF)" in the master list of all ACE-Asia datasets.
Questions about this dataset should be directed to the RAF Data Manager,
Ron Ruth, rafdmg@ucar.edu.
Table 2-1 PRODUCTION MASS STORE BITFILE LOG
Project no.: 2001-131 Project name: ACE-Asia
Aircraft: N130AR Scientist(s): B. Huebert, et al.
Data type: LRT Programmer(s): Chris Webster
Processor used: NIMBUS Project Mgr(s): R. Friesen, K. Laursen, A. Schanot
Output format: netCDF Production Proc.: R. Friesen, A. Schanot
MSS path name: /RAF/2001/131/LRT/fltno.cdf
MSS format: Transparent
------------------------------------------------------------------------
Start Date Start End File Size
fltno mm/dd/yyyy Time UTC Time UTC (Mbytes)
------------------------------------------------------------------------
RF01 03/30/2001 23:40:00 06:34:01 49.648180
RF02 04/01/2001 23:43:00 08:13:30 61.203012
RF03 04/04/2001 00:00:01 08:56:59 64.630872
RF04 04/06/2001 00:31:01 09:44:02 66.560744
RF05 04/08/2001 03:15:00 10:36:34 53.159996
RF06 04/11/2001 00:01:00 07:15:46 52.237712
RF07 04/11/2001 23:54:00 09:14:01 67.267712
RF08 04/13/2001 00:15:01 08:47:25 61.553720
RF09 04/16/2001 23:58:16 09:27:22 68.084080
RF10 04/17/2001 23:48:00 09:03:26 66.450640
RF11 04/19/2001 23:57:00 09:20:30 67.414768
RF12 04/22/2001 22:45:00 08:07:43 67.321144
RF13 04/23/2001 23:47:00 09:12:30 67.653788
RF14 04/24/2001 23:55:00 09:17:48 67.331072
RF15 04/27/2001 00:36:00 10:08:53 68.536252
RF16 04/29/2001 23:49:00 08:40:15 63.560236
RF17 04/30/2001 23:55:00 09:19:41 67.556176
RF18 05/02/2001 00:16:10 09:16:05 64.596064
RF19 05/03/2001 23:40:00 07:35:55 56.946784
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Table 2-2 Suggested ACE-Asia variable list
NCAR C-130
Name Units Description
---- ----- ------------------------------------------------
base_time Seconds since Jan 1, 1970.
time_offset Seconds since base_time.
PCAB mbar Interior Cabin Static Pressure
RICE Vdc Raw Icing-Rate Indicator
RSTB1 C Radiometric Surface Temperature
SWB W/M2 Shortwave Irradiance, Bottom
SWT W/M2 Shortwave Irradiance, Top
TEO3C ppbv Corrected TECO (UV) Ozone Concentration
UVB W/M2 Ultraviolet Irradiance, Bottom
UVT W/M2 Ultraviolet Irradiance, Top
DAY day Raw Tape Date Component
HOUR hours Raw Tape Time Component
MINUTE minutes Raw Tape Time Component
MONTH month Raw Tape Date Component
PITCH deg Aircraft Pitch Angle
ROLL deg Aircraft Roll Angle
SECOND s Raw Tape Time Component
THDG deg Aircraft True Heading Angle
VSPD M/s IRS-Computed Aircraft Vertical Velocity
YEAR year Raw Tape Date Component
ALTX M Altitude, Reference (MSL)
ATTACK deg Attack Angle, Reference
ATX C Ambient Temperature, Reference
CONC3_RPO N/cm3 FSSP-300 Concentration (all cells)
CONC6_LPC N/L 260X Concentration (all cells)
CONCF_LPI N/cm3 FSSP-100 Concentration (all cells)
CONCF_RPC N/cm3 FSSP-100 Concentration (all cells)
CONCN N/cm3 Condensation Nuclei (CN) Concentration
DBAR3_RPO uM FSSP-300 Mean Particle Diameter
DBAR6_LPC uM 260X Mean Particle Diameter
DBARF_LPI uM FSSP-100 Mean Particle Diameter
DBARF_RPC uM FSSP-100 Mean Particle Diameter
**DPXC C Dew Point Temperature, Reference
IRBC W/M2 Corrected Infrared Irradiance, Bottom
IRTC W/M2 Corrected Infrared Irradiance, Top
LATC deg GPS-Corrected Inertial Latitude
LONC deg GPS-Corrected Inertial Longitude
**MR g/kg Mixing Ratio, T-Electric
*PLWCC1 g/M3 Corrected PMS-King Liquid Water Content
PSURF mbar Calculated Surface Pressure
PSXC mbar Corrected Static Pressure, Reference
QCXC mbar Corrected Dynamic Pressure, Reference
**RHODT g/M3 Absolute Humidity, T-Electric Top
**RHUM % Relative Humidity
SOLAZ radians Solar Azimuth Angle
SOLDE radians Solar Declination Angle
SOLEL radians Solar Elevation Angle
SOLZE radians Solar Zenith Angle
SSLIP deg Sideslip Angle, Reference
TASX M/s Aircraft True Airspeed, Reference
THETA K Potential Temperature
THETAE K Equivalent Potential Temperature
THETAV K Virtual Potential Temperature
WDC deg GPS-Corrected Horizontal Wind Direction
WIC M/s GPS-Corrected Wind Vector, Vertical Gust Component
WSC M/s GPS-Corrected Horizontal Wind Speed
* For liquid water content (LWC) use PLWCC1 for flights 10, 11, 12, 15, 16,
17, 18, 19. Use PLWCC for flights 1,2. Use XGLWC for flights 3 through
9, 13, 14.
** For dew point (DP), water vapor (RHO, MR), and humidity (RH) use the
following:
For flights 1, 2, 3, 7, 9, 12, 14, 15, 17, 18, 19 use DPXC, RHODT,
MR,RHUM
For flights 4, 5, 6, 8, 10, 13, 16 use DPLA1, RHOLA1, MRLA1, RHLA1
For flights 11, use DPLA, RHOLA, MRLA, RHLA
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3.0 Quality Control
These 1 Hz frequency data have been processed and quality controlled by
NCAR/RAF.