Operation Manual Part 2

Aerosoft – Digital Aviation

CRJ-70 & CRJ-900

AOM PART 2

Systems Description

VOL

5-1-37

26-Jul-2017

1. SELECTED TEMPERATURE (cyan): Indicates the selected

temperature

2. ACTUAL TEMPERATURE (white): Indicates sensed

temperature

3. MANUAL (white): Indicates manual mode is selected.

4. SUPPLY DUCT TEMPERATURE (white): Displays sensed

temperature in the supply duct

ECAM MESSAGES

• HI TEMP (amber): High temperature detected

• AUTOFAIL (amber): Failure or pack in automatic mode is detected

• L/R PACK AUTOFAIL CAUTION (amber): Pack failed in automatic mode and is NOT switched to manual

mode

• L/R PACK TEMP CAUTION (amber): Temperature is > 85 °C

• L/R PACK CAUTION (amber): Pack failed independent of mode (manual / automatic)

• L/R PACK FAULT STATUS (white): Indicates a fault in the pack

• L/R PACK OFF STATUS (white): Indicates pack is switched off

• CKPT /CABIN TEMP MAN STATUS (white): Indicates that manual mode is selected

• RAM AIR STATUS (white): Indicates ram air valve is open.

• AFT CARGO OVHT CAUTION (amber): Temperatures over 40° sensed

• AFT CARGO SOV STATUS (white): Air-inlet shut-off valve failed to open.

AVIONICS COOLING SYSTEM

All electrical systems heat up during use. Same goes for all the avionic in the cockpit. Given the restricted

space, cooling is necessary to prevent the avionic from overheating. Two display (DSPLY) fans supply cold air to

the displays – only one of them is running during normal operation: on ground fan 2 and in flight fan 1.

Furthermore, two AVIONIC fans extract the heated air from behind the avionics. On ground fan 2 is powered

and in flight fan 1 is powered.

1. DISPLAY FANS CONTROLS

• GND ALT: Select fan 1

during ground operations

• NORM: Fans in exhaust

duct operate in automatic

mode to exhaust hot air from display and avionics compartments. Fan 1 used in flight, fan 2

used for ground operations