LOW TEMP ALTIMETRY Flashcards
What is the temperature error on altimeters?
4% height error per 10 deg C deviation from ISA
When are altitude correction for low temp used?
When ambient temp is at or below ISA -15 deg C
Are vectors, under radar control, from ATC low temp corrected?
ICAO recommends it but it’s not universally enforced
Shall a pilot low temp correct an ATC assigned altitude?
No
How are enroute MORA/MRA:s temp corrected?
ISA-15 to -24 = 10%
ISA-25 to -34 = 15%
ISA-35 to -45 = 20%
> ISA -45 = 25%
Is low temp correction applied to MSA/TAA?
Yes, shall be corrected. Assume the height is the same as the altitude.
When do you need approval before correcting for low temp?
When correcting for “AT” constraints.
Missed Approach Altitude(MAA) is an “AT” constraint
What altitudes are corrected for on a Precision Approach?
MSA
IAF
Profile altitudes
IF
FAF
DA
MAA
What altitudes are corrected for on an APV approach?
MSA
IAF
IF
DA
MAA
What altitudes are corrected for on a Non-precision approach?
MSA
IAF
IF
FAF
MDA
MAA
Describe how a manual correction for cold weather is done?
- Round down airport elevation to nearest 100 ft
- Calculate the heights. (Charted altitude-elevation)
- Get correction from table. Round down temp to nearest 5 deg column. Use nearest height row. If in between, use the higher row.
- Add correction to chart altitude
How do we low temp correct
1. All engine accleration height for T/O and Missed APP?
2. Eng out acceleration height for T/O and Missed APP?
- No correction needed. ACARS figures are valid as it uses input temp for T/O. For missed approach ISA +15 is used which is conservative in terms of performance
- No need for T/O. ACARS includes temp correction
For missed approach, eng out acc alt have to be corrected as per normal
