- Overview
- The Aircraft
- Instrumentation
- The Data
- Characteristics
- Flight Coordination Table
- The Files
- Size and Naming Conventions
- Formats
- Data Access and Contacts
- FTP Site
- Contacts
- References
The NASA ER2NAV data set is part of the atmospheric measurements collected in the intensive observation period of the Tropical Ocean Global Atmosphere-Coupled Ocean Atmosphere Response Experiment (TOGA-COARE). The ER-2 was deployed under the direction of John Arveson of the NASA Ames Research Center High Altitude Flight Facility.
The Aircraft
The NASA ER-2 is a high altitude, single pilot aircraft deployed globally in support of a variety of atmospheric research projects. It has a maximum altitude of 70,000 feet (21 km), a range of 3000 nautical miles, a maximum flight duration of 8 hours (nominal 6.5 hours) and a top speed of 410 knots true air speed. The aircraft accommodates about 2700 pounds (1200 kg) of payload and offers the following science support systems:
- Inertial navigation
- Satellite NBS Time Code receiver
- Navigation data recording system
- Real-time telemetry data link
Instrumentation
For the TOGA COARE campaign, the ER-2 payload consisted of:
- Cloud Lidar System
- Advanced Microwave Precipitation Radiometer (AMPR)
- Millimeter Imaging Radiometer (MIR)
- Radiation Measurement System (RAMS)
- Lightning Instrument Package (LIP)
- Electro-Optic Camera System (EOC)
Characteristics
The ER-2 navigation data set consists of navigation parameters gathered by the aircraft's onboard systems in support of the payload instruments. It includes times and georeferencing information which can be used to determine temporal and spatial coordinates associated with each measurement collected from the above instruments.
Flight Coordination Table
The following table relates the ER-2 NAV data files to ER-2 and DC-8 flight numbers and to the dates for the 13 mission flights of the NASA/TOGA COARE campaign. The objectives column is included for the convenience of the user; the mission objective was convection when it was forecast in the target area and radiation when it was not.
Date(UTC) ER-2 Flight DC-8 Flight ER-2 File Objective Jan 11-12 93-053 93-01-06 er2_3.dat Radiation Jan 17-18 93-054 93-01-07 er2_4.dat Convection Jan 18-19 93-055 93-01-08 er2_5.dat Convection Jan 25-26 93-056 93-01-09 er2_6.dat Radiation jan 31-Feb 1 93-057 93-01-10 er2_8.dat Radiation Feb 4 93-060 93-01-11 er2_10.dat Convection Feb 6 93-01-12 Convection Feb 7 93-061 er2_11.dat Feb 8-9 93-062 93-01-13 er2_12.dat Convection Feb 10-11 93-063 93-01-14 er2_13.dat Convection Feb 17-18   93-01-15   Convection Feb 20-21 93-065 93-01-16 er2_15.dat Convection Feb 22-23 93-066 93-01-17 er2_16.dat Convection Feb 23-24 93-067 93-01-18 er2_17.dat Radiation
Size and Naming Conventions
The ER-2 navigation data set contains 18 ASCII files ranging in size from ~1 MB to ~4MB with a total volume for the dataset of ~27 MB. Each file contains data from one flight, of which 13 were mission flights and 5 were ferry or pilot proficiency flights. The naming convention for the files is er2_X.dat where X is the flight number.
Data File Format
Each data file contains a header record that is formatted as described in the following table:
TABLE E-6A U2/USER PLUS DIGITIZED ANALOG VALUES HEADER INFORMATION CHARACTERS CONTENTS ---------- -------- RECORD 1 2 - 7 "FLIGHT" 9 - 14 The flight identifier, which consists of the last two digits of the fiscal year, a dash, and a three digit unique number that identifies the flight within the fiscal year (e.g. 92-001). 17 - 20 "DATE" 22 - 29 The data of the flight at liftoff, in the form MM/DD/YY, where MM gives the number of the month, DD gives the day YY gives the last 2 digits of the current year 32 - 34 "A/C" 36 - 38 Tail number of the aircraft (706, 708 or 709). 41 - 47 "TAKEOFF" 49 - 56 The takeoff time, in the form HH:MM/DD, where HH gives the hour (24-hour clock) MM gives the minute DD gives the day of the month at takeoff. 59 - 62 "LAND" 64 - 71 The landing time, in the same form as "TAKEOFF", except that DD gives the day of the month at landing. 82 - 101 "RECORDER UNIT NUMBER" 103 ID number of the navigation data recorder. 104 - 200 Blank RECORDS 2 - 5 Title that serves to label the contents of the data records. NOTE: Characters not explicitly mentioned here are filled with blanks, i.e. the ASCII code for "space". (END of Table E-6A) The data part of each file is formatted as described in the following table: TABLE E-6B U2/USER PLUS DIGITIZED ANALOG VALUES DATA RECORD FORMAT (English Units) CHARACTER CONTENTS --------- -------- 02 - 12 The time and day, in the form HH:MM:SS/DD, where HH gives the hour (24-hour clock) MM gives the minute SS gives the second DD gives the day of the month. 15 Time source indicator, "G" -- from GOES satellite "I" -- Internal time source 18 - 25 Latitude, hHH:MM.t, as follows: 18 h -- hemisphere, "N" for Northern, or "S" for Southern. 19 - 20 DD -- Degrees of latitude. 21 : -- separator between degrees and minutes. 22 - 25 MM.t -- Minutes and tenths of minutes of latutude, (with a decimal point). 27 - 35 Longitude, hDDD:MM.t, as follows: 27 h -- hemisphere, "W" for Western, or "E" for Eastern 28 - 30 DDD -- Degrees of longitude. 31 : -- separator between degrees and minutes. 32 - 35 MM.t -- Minutes and tenths of minutes of longitude, (with a decimal point). 37 - 41 Altitude, in feet (from 0 - 70000). 42 "space" if below 70000 feet, or "+" if over 70000 feet, (if over 70000 feet, the Altitude (37-41) will contain 70000.) 45 - 47 True Air Speed, in nautical miles per hour. 49 - 53 Aircraft Pitch, in degrees, given to tenths (with a decimal point). Positive indicates nose up. 55 - 59 Aircraft Roll, in degrees, given to tenths (with a decimal point. Positive indicates right roll, i.e. right wing down. 61 - 66 True heading, in degrees, given to tenths (with a decimal Point). Zero degrees indicates North, positive to the East of North. (90 indicates due East; 180 indicates South; and 270 indicates West.) 67 - 72 North-South velocity, in nautical miles per hour. 74 - 77 East-West velocity, in nautical miles per hour. 79 - 82 Vertical velocity, in feet per second. 85 - 87 Ground Speed, in nautical miles per hour. 94 - 96 Computed ground speed, in nautical miles per hour. (Square root of the sum of the squares of the North-South and East-West velocities.) 100 - 103 Computed wind speed, in nautical miles per second. (The vector difference of the True air speed and True heading and North-South and East-West velocities. 107 - 109 Computed wind direction, in degrees from North (clockwise is positive). 113 - 116 Computed vertical velocity (in feet per second). Computed from the altitude difference and time difference between consecutive records. 122 - 124 Computed angle of attack (degrees), i.e. Arcsine. (Vertical velocity divided by ground speed.) 134 - 138 Static air temperature in degrees C. Computed from the first digitized analog value, if recorded. UNITS/SCALES OF THE DAV'S DEPEND UPON THE QUANTITY MEASURED BY EACH DAV 156 - 163 Values for first Digitized Analog Value 164 - 171 Values for second Diigitized Analog Value 172 - 179 Values for third Digitized Analog Value 180 - 187 Values for fourth Digitized Analog Value 188 - 200 Blank NOTES ----- Characters not explicitly mentioned here are filled with blanks. Characters corresponding to parameters that were not recorded during the flight are set to blanks. (End of Table E-6B)
FTP Site
The ER-2 NAV data files are tarred and compressed in the file "er2.tar.Z." ER-2 flight track images were produced by the AMPR team for 12 mission flights. The naming convention for these files is "amprft93.XXX_toga_track.gif" where XXX is the Julian day on which the flight took off.
The data may be retrieved from this document
ER-2 NAV data
or directly via ftp:
ftp disc.gsfc.nasa.gov
logon: anonymous
passwd: <your internet address >
cd data/toga_coare/aircraft/nasa_er2/navPoints of Contact
For questions about Goddard DAAC datasets, contact:
Pat Hrubiak EOS Distributed Active Archive Center(DAAC) Code 610.2 NASA Goddard Space Flight Center Greenbelt, Maryland 20771 Internet: hrubiak@disc.gsfc.nasa.gov (301) 286-1381 (voice) (301) 286-1775 (FAX) For detailed information about the ER-2 aircraft, contact the ER-2 Aircraft Program at the Dryden Flight Research Facility.
NASA/TOGA COARE Science Data Workshop - II Proceedings, March 15-17 1994, Albuquerque, New Mexico, NASA TOGA COARE Project Office, M.S. 483, NASA Langley Research Center, Hampton, VA 26381-0001
ER-2 Flight Summary Report, NASA ER-2 Deployment, Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment, Aircraft Data Facility, NASA Ames Research Center, Mail Stop 240-6, Moffett Field, CA 94035-1000
Mission Summary Reports, TOGA COARE, November 1993, NASA TOGA COARE Project Office, NASA Langley Research Center, Mail Stop 483, Hampton, VA 23666
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