TBD ADD: TAMAIR 56 C TAMDAR airline MADIS ACARS Variables - Numeric ------------------------------------------------------------------------------------------- Code Name Units Max Notes Database QC Level* FSL AWIPS ------------------------------------------------------------------------------------------- DD wind direction deg 1 1 X X FF wind speed m/s 1 1 X X U u wind component m/s 1 1 X X V v wind component m/s 1 1 X X T air temperature K 2 2 X X TV virtual temperature kg/kg 2 2 X X TD dewpoint temperature K 2 3 X X RH relative humidity % 2 3 X X Q specific humidity kg/kg 2 3 X X DPD dewpoint depression K 2 3 X X AH absolute humidity g/(m**3) 2 3 X X WVMR water vapor mixing ratio g/kg 2 3 X X REPWVQC reported water vapor QC code 0 4 X X RHPROBE rh in probe 0 4 X RH1 rh sensor 1 % 0 19,20 X RH2 rh sensor 2 % 0 19,20 X RHUNCER rh uncertainty % 0 19,20 X TDUNCER dewpoint uncertainty K 0 19,20 X MACH mach number 0 4 X TASPEED true air speed m/s 1 19 X MEDEDR median eddy dissipation rate m**(2/3)/s 1 5,21,22 X MAXEDR maximum eddy dissipation rate m**(2/3)/s 1 5,21,22 X VACC vertical acceleration m/s/s 0 X PEAKVG peak vertical gust m/s 0 X TURBIDX turbulence index code 1 17,21,22 X X HT pressure altitude m 2 6 X X GPSHT geometric height determined by GPS m 0 19 X BAROHT barometric-corrected height m 0 6 X P pressure Pa 2 6 X X LAT latitude deg N 1 X X LON longitude deg E 1 X X HEAD heading deg 0 X FLPHASE phase of flight code 0 16 X X ICECOND icing condition code 1 12,21 X ROLL aircraft roll angle flag code 0 7 X X TINT time interpolation indicator code 0 8 X LINT location interpolation indicator code 0 8 X DINT decoding-correction indicator code 0 9 X LTINT loc./time interpolation indicator code 0 8 X RMEDEDR reported median EDR m**(2/3)/s 0 5 X RMAXEDR reported maximum EDR m**(2/3)/s 0 5 X REPRH reported rh 0 4 X TPREC temperature precision K 0 X LLSPEC original specification of lat/lon code 0 15 X PLATTYP data platform type code 0 13 X X DATASRC source that provided the data code 0 14 X X MADIS ACARS Variables - Character ------------------------------------------------------------------------------------------- Code Name Character Notes Database Size FSL AWIPS ------------------------------------------------------------------------------------------- REPGSTA reporting ground station 4 10 X X ORIGAPT originating airport 6 10 X DESTAPT destination airport 6 10 X RCPTIME receipt time 9 11 X X TRBTIME time of maximum turbulence 9 19 X FLNUM flight number 13 X Notes 1. Wind speed and direction are reported and stored in the database. The user can optionally select u & v wind components and those will be calculated and returned. The QC results from speed and direction will be used In either case, and if one of the map projections has been selected via the MSETDOM call, the winds will be rotated to match the projection. 2. Air temperature is the temperature variable stored in the database. For aircraft that are also reporting dewpoint temperature (a minority) the user can optionally select virtual temperature, which will then be calculated by the MADIS API. The QC results from air temperature will apply in either case. Also note that if virtual temperature cannot be calculated (missing or bad dewpoint or pressure), and the air temperature passed all QC checks, the air temperature will be returned instead, and a QC data descriptor value of "T" will be assigned. 3. In the FSL database relative humidity is the moisture variable stored for TAMDAR data, and water vapor mixing ratio is used for non-TAMDAR data. Relative humidity is the form of moisture in the AWIPS database. The user can optionally select any of these variables, specific humidity, dewpoint depression, or absolute humidity and these values will be calculated by the MADIS API. In all cases, the QC results from the dewpoint temperature will be used (with the FSL database, there's currently no QC in the AWIPS database). 4. The dewpoint temperatures are calculated from data reported by aircraft equipped with the Water Vapor Sensing System (WVSS). While the dewpoint temperatures are correct, the user should be aware that there are inconsistencies related to the decoding at FSL of the other water-vapor-related variables (rh probe, reported rh, water vapor mixing ratios, reported water vapor QC, and mach number). Therefore, the QC'ed moisture information returned from the MADIS API (dewpoint, rh, ah, dewpoint depression) are all calculated from the dewpoint temperatures. Reported water vapor QC codes -- FSL database: Value Meaning ----- ------- 45 Missing data 48 Normal operations, ground speed > 60 knots 49 Normal operations, nonmeasurement mode, ground speed < 60 knots 50 Small RH, RH measured is < 1.5%; RH set to 1.5% 51 Humidity element is wet. RH at 5.0 volts for < 120 seconds 52 Humidity element contaminated. RH at 5.0 volts for > 120 seconds 53 Heater fail 54 Heater fail and wet/contaminated humidity element 55 Single validity bad. One or more of the input parameters for the mixing ratio calculation are invalid: TOT_PRESS, MACH TAT_WVSS, or RH. If RH is full scale, RH is considered valid to allow wet/contaminated status to be posted. 56 Numeric error. Calculated mixing ratio at or above 100, below 0.1-9, or negative, or absolute value of denominator of calculations is less than 10-15. 57 Dew point is greater than temperature Reported water vapor QC codes -- AWIPS database: Value Meaning ----- ------- 0 Normal operations, measurement mode 1 Normal operations, nonmeasurement mode 2 Small RH 3 Humidity element is wet 4 Humidity element contaminated 5 Heater fail 6 Heater fail and wet/contaminated humidity element 7 At least one of the input parameters used in the calculation of mixing ratio is invalid 8 Numeric error 9 Sensor not installed 63 Missing data 5. The reported eddy dissipation rate (EDR) variables contain both data values and embedded code values that are used to indicate reasons why no data values are available. Therefore, a user only interested in the data values themselves should request the median and maximum EDR variables. Reported EDR "no data" codes: Value Meaning ----- ------- 2.54 Bad CGA - Insufficient vertical acceleration data 2.53 Bad ALT - Altitude out of range 2.52 Bad MACH - Speed out of range 2.51 Bad MASS - Aircraft mass out of range 2.50 Bad FLAP - Flap angle out of range 2.49 Bad AUTO - Autopilot off 6. The altitude-determining physical variable is pressure. This is converted to altitude by using the U.S. Standard Atmosphere calculation. The standard atmosphere is used at all altitudes and under all pressure conditions. Thus, for instance, it is possible to have ACARS altitudes below ground level on days with high atmospheric pressure. (This is in contrast to other aviation reports such as voice pireps that use a standard atmosphere to compute altitude above 18,000 ft (MSL), but use the current altimeter setting for lower altitudes). The barometric-corrected height is used instead of a pressure altitude below approximately 18,000 ft in AMDAR reports from Japanese airlines. The user can request either altitude or pressure, and the MADIS API will do the conversion and return the requested variable. In either case, the QC results from the altitude variable will be applied. 7. Aircraft roll angle flag -- FSL database: Value Meaning ----- ------- 45 missing 66 roll > 5 degrees 71 roll <= 5 degrees 78 not reported Aircraft roll angle flag -- AWIPS database: Value Meaning ----- ------- 0 good 1 bad 8. Some high-resolution ascent/descent observations are reported without times, and/or location information. In these cases the FSL decoder interpolates the values and indicates that in the LINT and TINT interpolation indicator codes. The decoder used to create the data in the AWIPS database combines these into one indicator, LTINT. Here are the possible values for these variables: LINT, TINT -- FSL database: Value Meaning ----- ------- 105 interpolated 114 reported LTINT -- AWIPS database: Value Meaning ----- ------- 0 time interpolated, latitude and longitude reported 1 time reported, latitude and longitude interpolated 2 time, latitude, and longitude interpolated 3 time, latitude, and longitude reported 7 missing value 9. Decoding-correction indicator: Value Meaning ----- ------- 84 temperature correction 102 longitude and wind direction flipped and observation time set to the report receipt time 108 lat/lon correction (other than interpolation) 114 no correction applied 116 observation time set to the report receipt time 10. Not all ACARS reports (North America) include the originating and destination airport variables, and none of the AMDAR (most European and Asian reports) have them. When the ACARS reports are downlinked they are picked up by a reporting ground station which exist at various airports around the U.S. 11. The observation time returned by the MACARSSTA subroutine is generally used as the nominal time of the data for most applications, however, for interested users, the time of actual ground data receipt are available in the receipt time variable for ACARS reports. For AMDAR reports in the FSL database, and for all reports in the AWIPS database, this is not the time of receipt, but a time reported in the header of the raw data. All times reported in the MADIS API are in Universal Coordinated Time, with the format of "YYJJJHHMM", where: YY = 2-digit year (good from 1980 - 2179) JJJ = Julian date of the year (1-366) HH = Hour (0-23) MM = Minute (0-59) If the receipt time is missing, the 9-character field will be set to all blanks, e.g., " ". 12. Icing condition: Value Meaning ----- ------- 0 no ice is present 1 ice is present - Delta 4 ice is present - TAMDAR 13. Data platform type -- FSL database: Value Meaning ----- ------- 1 vertical-acceleration measuring aircraft 2 eddy dissipation rate measuring aircraft 3 vapor measuring aircraft 4 vertical gust measuring aircraft 5 ice measuring aircraft 6 eddy dissipation rate, RH, ice measuring aircraft Data platform type -- AWIPS database: Value Meaning ----- ------- 0 automatic 1 manned 2 hybrid, both manned and automatic 14. Source that provided the data -- FSL database: Value Meaning ----- ------- 0 ACARS (direct to FSL from airlines) 1 MDCRS (from TG's BUFR file from ARINC) 2 appeared in both ACARS and MDCRS data streams 3 AMDAR data, including LH BUFR data 4 TAMDAR data from AirDat, LLC 5 Canadian AMDAR data from CMC 6 European AMDAR data Source that provided the data -- AWIPS database: Value Meaning ----- ------- 0 ASDAR 1 ASDAR (ACARS also available but not operative) 2 ASDAR (ACARS also available and operative) 3 ACARS 4 ACARS (ASDAR also available but not operative) 5 ACARS (ASDAR also available and operative) 15. Original specification of latitude and longitude: Value Meaning ----- ------- 0 Actual location in seconds 1 Actual location in minutes 2 Actual location in degrees 3 Actual location in decidegrees 4 Actual location in centidegrees 5 Referenced to checkpoint in seconds 6 Referenced to checkpoint in minutes 7 Referenced to checkpoint in degrees 8 Referenced to checkpoint in decidegrees 9 Referenced to checkpoint in centidegrees 10 Actual location in tenths of a minute 11 Referenced to checkpoint in tenths of a minute 16. Phase of flight: Value Meaning ----- ------- 3 Level flight, routine observation (LVR) 4 Level flight, highest wind encountered (LVW) 5 Ascending (ASC) 6 Descending (DES) 17. The turbulence index is calculated from the median and maximum eddy dissipation rates, as follows: Value Meaning ----- ------- 0 median < 0.1 | maximum < 0.1 1 median < 0.1 | 0.1 <= maximum < 0.2 2 0.1 <= median < 0.2 | 0.1 <= maximum < 0.2 3 median < 0.1 | 0.2 <= maximum < 0.3 4 0.1 <= median < 0.2 | 0.2 <= maximum < 0.3 5 0.2 <= median < 0.3 | 0.2 <= maximum < 0.3 6 median < 0.1 | 0.3 <= maximum < 0.4 7 0.1 <= median < 0.2 | 0.3 <= maximum < 0.4 8 0.2 <= median < 0.3 | 0.3 <= maximum < 0.4 9 0.3 <= median < 0.4 | 0.3 <= maximum < 0.4 10 median < 0.1 | 0.4 <= maximum < 0.5 11 0.1 <= median < 0.2 | 0.4 <= maximum < 0.5 12 0.2 <= median < 0.3 | 0.4 <= maximum < 0.5 13 0.3 <= median < 0.4 | 0.4 <= maximum < 0.5 14 0.4 <= median < 0.5 | 0.4 <= maximum < 0.5 15 median < 0.1 | 0.5 <= maximum 16 0.1 <= median < 0.2 | 0.5 <= maximum 17 0.2 <= median < 0.3 | 0.5 <= maximum 18 0.3 <= median < 0.4 | 0.5 <= maximum 19 0.4 <= median < 0.5 | 0.5 <= maximum 20 0.5 <= median | 0.5 <= maximum 63 Missing value 18. The platform with station name 00001152 is not actually a single aircraft. This is a catch-all station name for reports that don't indicate the actual aircraft. Therefore, the position consistency and temporal consistency checks aren't applied. 19. The RH1, RH2, RHUNCER, TDUNCER, TASPEED, GPSHT and TRBTIME variables are only available for TAMDAR reports. See note 11 for a description of how TRBTIME will be formatted by the MADIS API. 20. The TAMDAR reports include two sensors used for relative humidity. A "consensus RH" is also reported as the primary moisture variable, and this is what's used for RH, TD, etc. Users interested in seeing the values from both sensors can select the RH1 and RH2 variables. The RH uncertainty variable is the theoretical RSS (root-summed-squared) uncertainty of the consensus RH value in percent. Two error source components are used in the RSS calculation: temperature uncertainty (assumed to be +/- 0.4C) and the RH sensor uncertainty (assumed to be +/- 2% absolute error [not RH times 2%]). Other inputs to the calculation are air temperature, pressure altitude and indicated air speed. The uncertainty is additive with the reported humidity, so if RH is 30% and RHUNCER is 20%, the estimated range of the RH is 30% +-20%, i.e., 10-50%. Dewpoint uncertainty is derived from the RH uncertanty variable in the following way. If the RH uncertainty is >= 0.49, the dewpoint uncertainty is set to 999. Otherwise, two subsidiary dewpoints are calculated by assuming the RH is 1) RH + RHUNCER, and, 2) RH - RHUNCER. The dewpoint uncertainty is one-half the difference between 1) and 2). 21. The MEDEDR, MAXEDR, TURBIDX and ICECOND variables for TAMDAR reports are accompanied by level 1 QC results from the TAMDAR provider. These variables can also be reported by the other providers, but these do not have any QC. Therefore, API users interested in seeing the data from these providers should request all data, not just data passing any QC level. 22. The eddy dissipation rates available in the ACARS and TAMDAR reports are calculated using different algorithms. The NCAR algorithm used for ACARS calculates EDR from fluctuations in the vertical motion of the aircraft (current algorithm), or fluctuations in the vertical wind (proposed new algorithm). The TAMDAR algorithm calculates EDR from fluctuations in the horizontal wind, as revealed by fluctuations in the indicated airspeed. When the turbulence is isotropic, the NCAR and TAMDAR algorithms should agree. * The QC information is only available with the FSL database. For more information contact madis support.