In-situ aircraft data from the MOZAIC Database:data set description

Data set source Information on available Data Data Processing Data format References

Data selection page

The MOZAIC system has been developed for automatic ozone, water vapour and temperature measurements during in service flights aboard A340 aircraft. MOZAIC is an European cooperation between the 'Laboratoire d'Aerologie' of CNRS (Centre National de la Recherche Scientifique) and Airbus Industrie. Several organizations participate to this project : the KFA (Kennforschungsanstalt) Julich and the Max Planck Institut (MPI) Mains in Deutschland, Meteo France, the Cambridge University in England and the Tenerife University in Portugal.

1. Ascending part:
   The averaged values with altitude interval of about 150 m.
2. Crusing altitude:
   The averaged values with a gap of 1 minute.
3. Descending profile:
   Averages values with altitude interval of about 150 m.

Here is the way the files are built:

1. All along the flight, two tests are done on altitude and time. We read each record which gives values: H1, for the altitude, and T1 for the time.(normaly every 4 seconds), then we read the following records and do the test:
   if (|H1-H| >= 150 meters or |T1-T| >= 60 seconds) then

   |

   we make the averages of the i values of the interval

   |

   |

   |

   endif
   and so on.

   The box size is 150 m height x 60 seconds time
   Then the profiles are built with mean values on intervals of either 150 meters or 60 seconds.

2. With regard to the RH validity:
   RH=0 no data, these values are excluded for the calculation of the averaged values.
   RH=1,2,3 these values are taken in account for the calculation of the average.
   RH=1 measurement ok
   RH=2 Below detection limit of RH
   RH=3 Data have limited reliability
   If no measure is available, the averaged humidity takes the default value -999.9.

Remarks :
1. "baro altitude" is the geopotential height computed from the pressure measurement using the ICAO standard atmospheric profile. "baro altitude" data contain the same information as "pressure" data
2. "radio altitude" is the altitude above surface and is switched on only during take-off and landing phases.
3. Wind direction is the direction from which the wind is blowing. Origin is North. The direction increases clockwise. As a result, wind blowing from North has direction 0 degree, wind blowing from East has direction 90 degrees.
4. static temperatures : "A340 stat. temp." is provided by the aircraft computer. "static temp." is computed from the MOZAIC sensors.
5. H2O Relative Humidity (with respect to liquid water) is derived from the output of the capacitive sensor, the pressure and temperature conditions in the measuring cell (Rosemount housing) together with static pressure and temperature conditions. H2O mass mixing ratio is computed from the Relative humidity, the static temperature and pressure. It therefore does not contain any new piece of information.
6. H2O mixing ratio is computed from the Goff-Gratch formula.

Data format

LADD-MM-YY,KFADD-MM-YY,CNRMDD-MM-YY,VersionI.I

flight: MXXXXXXX on yy-mm-dd NL=XX from -> to NL=XX

      format(f6.2,1x,f7.2,1x,3(i2.2),1x,3(i2.2),1x,f8.1,1x,f7.1,
     +   1x,i7,1x,f6.2,2(1x,f7.2),1x,f7.2,1x,f7.2,1x,i5,1x,f5.1,
     +   1x,f6.1,1x,i2,1x,i3,1x,f7.3)