FlightDetent
16th Jul 2019, 08:12
Oh not again, :) the winter is coming...
Are there any opinions about the DEFINITION / MEANING of the word compensation in this one EASA Air-OPS (https://www.easa.europa.eu/sites/default/files/dfu/Air%20OPS%20Easy%20Access%20Rules_Rev.12_March%202019.pdf) paragraph?
Reference: AMC2 SPO.OP.116 Performance-based navigation — aeroplanes and helicopters
MONITORING AND VERIFICATION(d) Altimetry settings for RNP APCH operations using Baro VNAV
(2) Temperature compensation
(A) the flight crew should not commence the approach when the aerodrome temperature is outside the promulgated aerodrome temperature limits for the procedure unless the area navigation system is equipped with approved temperature compensation for the final approach;
(B) when the temperature is within promulgated limits, the flight crew should not make compensation to the altitude at the FAF and DA/H;
(C) since only the final approach segment is protected by the promulgated aerodrome temperature limits, the flight crew should consider the effect of temperature on terrain and obstacle clearance in other phases of flight.
In the (B) above, what are the arguments that the word compensation stands for either
- a feature of the airborne equipment (i.e. activating a temperature compensation algorithm of the FMC)
- a pilot's cognitive task (i.e. applying a temperature correction additive to a published value)
In the search for an answer myself, below is what I found in the regulation. I am reasonably certain the list is exhaustive, all appearances of words correction / compensation / temperature in the context of Baro VNAV.
(b) The operator should also consider: [...] (1) corrections for temperature and pressure variations from standard values;
(b) Ground training [...] (2) General concepts of RNP AR APCH operation [...] (ii) [..] should include [...] in particular [...](K) the temperature compensation: Flight crew members operating avionics systems with compensation for altimetry errors introduced by deviations from ISA may disregard the temperature limits on RNP AR APCH procedures if flight crew training on use of the temperature compensation function is provided by the operator and the compensation function is utilised by the crew. However, the training should also recognise if the temperature compensation by the system is applicable to the VNAV guidance and is not a substitute for the flight crew compensating for the temperature effects on minimum altitudes or the DA/H
(a) Modification of flight plan [...] not be authorised to fly a published RNP AR APCH procedure unless [...]
The only other acceptable modification to the loaded procedure is to change altitude and/or airspeed waypoint constraints on the initial, intermediate, or missed approach segments flight plan fixes (e.g. to apply temperature corrections or comply with an ATC clearance/instruction).
(j) Temperature compensation
For aircraft with temperature compensation capabilities, the flight crew may disregard the temperature limits on RNP procedures if the operator provides pilot training on the use of the temperature compensation function. It should be noted that a temperature compensation by the system is applicable to the VNAV guidance and is not a substitute for the flight crew compensating for temperature effects on minimum altitudes or DA/H. The flight crew should be familiar with the effects of the temperature compensation on intercepting the compensated path as described in EUROCAE ED-75C/RTCA DO-236C Appendix H.
The threads on the topic so far:
https://www.pprune.org/tech-log/571852-cold-temperature-corrections-lnav-vnav-minima.html, https://www.pprune.org/tech-log/601732-cold-temp-corrections-lnav-appr.html, https://www.pprune.org/tech-log/607100-lnav-vnav-barovnav-approach.html, https://www.pprune.org/tech-log/614852-temperature-correction-baro-vnav-approach.html, https://www.pprune.org/tech-log/616000-rnp-approaches-question-about-apv-version-low-temperature.html
Are there any opinions about the DEFINITION / MEANING of the word compensation in this one EASA Air-OPS (https://www.easa.europa.eu/sites/default/files/dfu/Air%20OPS%20Easy%20Access%20Rules_Rev.12_March%202019.pdf) paragraph?
Reference: AMC2 SPO.OP.116 Performance-based navigation — aeroplanes and helicopters
MONITORING AND VERIFICATION(d) Altimetry settings for RNP APCH operations using Baro VNAV
(2) Temperature compensation
(A) the flight crew should not commence the approach when the aerodrome temperature is outside the promulgated aerodrome temperature limits for the procedure unless the area navigation system is equipped with approved temperature compensation for the final approach;
(B) when the temperature is within promulgated limits, the flight crew should not make compensation to the altitude at the FAF and DA/H;
(C) since only the final approach segment is protected by the promulgated aerodrome temperature limits, the flight crew should consider the effect of temperature on terrain and obstacle clearance in other phases of flight.
In the (B) above, what are the arguments that the word compensation stands for either
- a feature of the airborne equipment (i.e. activating a temperature compensation algorithm of the FMC)
- a pilot's cognitive task (i.e. applying a temperature correction additive to a published value)
In the search for an answer myself, below is what I found in the regulation. I am reasonably certain the list is exhaustive, all appearances of words correction / compensation / temperature in the context of Baro VNAV.
(b) The operator should also consider: [...] (1) corrections for temperature and pressure variations from standard values;
(b) Ground training [...] (2) General concepts of RNP AR APCH operation [...] (ii) [..] should include [...] in particular [...](K) the temperature compensation: Flight crew members operating avionics systems with compensation for altimetry errors introduced by deviations from ISA may disregard the temperature limits on RNP AR APCH procedures if flight crew training on use of the temperature compensation function is provided by the operator and the compensation function is utilised by the crew. However, the training should also recognise if the temperature compensation by the system is applicable to the VNAV guidance and is not a substitute for the flight crew compensating for the temperature effects on minimum altitudes or the DA/H
(a) Modification of flight plan [...] not be authorised to fly a published RNP AR APCH procedure unless [...]
The only other acceptable modification to the loaded procedure is to change altitude and/or airspeed waypoint constraints on the initial, intermediate, or missed approach segments flight plan fixes (e.g. to apply temperature corrections or comply with an ATC clearance/instruction).
(j) Temperature compensation
For aircraft with temperature compensation capabilities, the flight crew may disregard the temperature limits on RNP procedures if the operator provides pilot training on the use of the temperature compensation function. It should be noted that a temperature compensation by the system is applicable to the VNAV guidance and is not a substitute for the flight crew compensating for temperature effects on minimum altitudes or DA/H. The flight crew should be familiar with the effects of the temperature compensation on intercepting the compensated path as described in EUROCAE ED-75C/RTCA DO-236C Appendix H.
The threads on the topic so far:
https://www.pprune.org/tech-log/571852-cold-temperature-corrections-lnav-vnav-minima.html, https://www.pprune.org/tech-log/601732-cold-temp-corrections-lnav-appr.html, https://www.pprune.org/tech-log/607100-lnav-vnav-barovnav-approach.html, https://www.pprune.org/tech-log/614852-temperature-correction-baro-vnav-approach.html, https://www.pprune.org/tech-log/616000-rnp-approaches-question-about-apv-version-low-temperature.html