PPRuNe Forums - View Single Post - Cold temperature corrections on LNAV/VNAV minima
Old 17th Dec 2015, 17:45
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JammedStab
 
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Originally Posted by Goldenrivett
This document http://www.developpement-durable.gou...NSS__ENGv3.pdf says that no temperature corrections are required if the airport is at or above the minimum published on the chart.

If the temperature is below the published minimum then:
"7.5.4 Case of temperatures below minimum temperatures published on the approach chart

On the RNAV(GNSS) approach charts for which there is an APV BaroVNAV approach (presence of LNAV/VNAV minima), a minimum temperature use is published.
As a general rule, pilots should not use the FMS (Baro)VNAV function when the temperature is below the temperature limit published on the approach chart.
The associated non-precision approach (LNAV) can be performed but management of the vertical plane should use another flight technique (vertical speed (V/S) or flight path angle (FPA).
Pilots should then apply the cold temperature corrections necessary to comply with the different published minimum altitudes, i.e.:
- The altitude heights for the final segment (FAF, SDF, altitude/distance table);
- The MDA/H; and
- The V/S and/or FPA values. "
That is interesting. But it leaves things potentially open to interpretation. They should specifically mention whether the MDA needs to have a temperature correction as this is very important.
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