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As shown below, ICAO doc 8168 (PANS OPS) says that cold temperature correction have to be applied on initial and intermediate segments and on the DA and MDA (and missed approache altitudes). But why final approach segment is not mentioned here? We don't have to apply correctons for FAF/FAP altitude?

1.7 COLD TEMPERATURE CORRECTION

1.7.1 Temperatures lower than those of the standard atmosphere result in the actual altitude of an aircraft being lower than that indicated by the barometric altimeter. As a consequence, the MOC actually achieved could be lower than the prescribed MOC. In order to prevent this, the pilot shall correct for low temperatures. The pilot is responsible for any necessary cold temperature corrections to all published minimum altitudes/heights in both conventional and PBN procedures. This includes:

a) the altitudes/heights for the initial and intermediate segment(s);

b) the decision altitude/height (DA/H) or minimum descent altitude/height (MDA/H); and

c) subsequent missed approach altitudes/heights.

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The final approach segment is designed to be safeguarded against the effects of low temperatures (some times a minimum temperature applies)

The explanation is actually given just below the paragraph you quoted from doc 8168, in the section 1.7.2:

1.7.2 The final approach path vertical path angle (VPA) on a 3D approach operation which is based on barometric vertical navigation (baro-VNAV) criteria is safeguarded against the effects of low temperature by the design of the procedure. This will ensure that the effective VPA at the minimum temperature published on the chart will not be less than 2.5° and has been obstacle assessed. By applying the cold temperature correction to this procedure type the nominal VPA will actually be flown. This can be achieved by manual application of the correction by the pilot, or in some cases where certified systems are used, through automatic application of the correction by an FMS.

Note.— For more information on the use of automated systems for temperature compensation, see the Performance-based Navigation (PBN) Manual (Doc 9613).

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    $\begingroup$ Your answer seems to only address 3D approaches (i.e., approaches with lateral and vertical guidance ILS, APV's, etc.). What about the FAF's on a non-precision approach (e.g. localizer only, LNAV, etc.) per the OP's question? $\endgroup$
    – RTO
    Nov 11, 2022 at 14:38
  • $\begingroup$ @757toga Good point. The PANS OPS doesn't say anything about non-precision approaches. You have any idea why? $\endgroup$
    – DeltaLima ♦
    Nov 11, 2022 at 23:19
  • $\begingroup$ Well, 1.7.1 in the OP's question references "MDA" (in 1.7.1 (b)), which applies to non-precision approaches. So, it's possible that the non-precision "FAF" issue is inherently incorporated within 1.7.1 language since the "intermediate" segment terminates at the FAF (for non-precision approaches). If a low temp corrected indicated altitude is flown during the intermediate segment the crew should be at the non-precision FAF at a low temp corrected altitude. Just a thought. $\endgroup$
    – RTO
    Nov 12, 2022 at 0:54
  • $\begingroup$ @757toga I considered that as well, but what about step down approaches that have altitude constraints after the FAF such as in this question. Although that question relates to a US approach, perhaps this there is a difference in this regard between PANS OPS and TERPS $\endgroup$
    – DeltaLima ♦
    Nov 12, 2022 at 12:21

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