SYSTEMS LAB / PRESSURISATION
Cabin pressure and landing field elevation
EICAS shows cabin altitude in feet, cabin rate in feet per minute and differential pressure in psi. Cabin ALT is pressure-equivalent altitude inside the cabin, not the aircraft’s barometric altitude.
Landing field elevation
FSS says AUTO displays the FMS destination in green. Manual LFE CTRL displays the entered elevation in cyan with an M. Cabin altitude and landing field elevation are separate values.
FSS’s EICAS page says LFE should appear in AUTO and manual LFE CTRL. The sampled E175 1.0.1 frame has no LFE field; FSS does not explain the difference [26, 103].
HI FIELD appears in high-altitude operation mode. FSS uses green for normal indications, amber for caution and red for a cabin-altitude warning [103].