PRESSURISATION Flashcards
HOW MANY OUTFLOW VALVES ARE THERE?
TWO: ONE ELECTRO-PNEUMATIC AND ONE PNEUMATIC OUTFLOW VALVES
THE PNEUMATIC OUTFLOW VALVE:
IS SLAVED TO THE ELECTRO-PNEUMATIC OUTFLOW VALVE IN AUTOMATIC MODE ONLY
IN NORMAL OPERATION, WITHOUT FAILURE, THE DIGITAL CONTROLLER USES AS REFERENCE
THE AIRCRAFT STATIC AIR PRESSURE GENERATED BY:
ADC 1 AND CM 1 ALTIMETER BARO SETTING
WHAT ARE THE CORRECT INDICATIONS DURING A PRESSURISATION SYSTEM TEST?
THE AMBER FAULT LIGHT IN THE MAN PB
THE LANDING ELEVATION INDICATOR DISPLAYS ALTERNATIVELY 18800 AND -8800 C)
THE TEST IS INHIBITED IN FLIGHT
IF AUTOMATIC PRESSURISATION CONTROL IS DESIRED, IN WHICH POSITION SHOULD THE
“MAN RATE KNOB” BE PLACED:
NORM
WHAT DO YOU SET IN “AUTO PRESS PANEL” BEFORE EACH FLIGHT?
LANDING AIRPORT FIELD ELEVATION, USING QNH OR ZERO IF USING QFE
HOW HIGH ABOVE TAKE-OFF ELEVATION CAN THE AIRCRAFT BE OPERATED WITHOUT
CANCELLING THE “AUTOMATIC RETURN” FEATURE?
3500 FT ABOVE TAKE-OFF FIELD ELEVATION
THE MAXIMUM CABIN RATE OF CLIMB, UP TO 20 000 FT IN AUTO MODE IS
+550 FT/MIN
WHAT IS THE MAXIMUM CABIN DIFFERENTIAL PRESSURE?
POSITIVE 6.35 PSI, LIMITED BY A MANOMETRIC CAPSULE
NEGATIVE 0.5 PSI, LIMITED BY A NON-RETURN VALVE
WHAT IS THE MAXIMUM NORMAL CABIN ALTITUDE AT FL250?
6 740 FT
HOW IS THE SYSTEM PROTECTED AGAINST EXCEEDING THE MAXIMUM CABIN DIFFERENTIAL
PRESSURE?
BOTH OUTFLOW VALVES INCORPORATE A MANOMETRIC CAPSULE (ANEROID) TO HOLD
THE VALVE OPEN SUFFICIENTLY TO PREVENT OVERPRESSURE
IN AUTO, WHAT IS THE HIGHEST CABIN RATE OF DESCENT AVAILABLE WITH THE DESCENT
RATE PB RELEASED (NORM):
-400FT/MIN
IN AUTO, WHAT IS THE HIGHEST CABIN RATE OF DESCENT AVAILABLE WITH THE DESCENT
RATE PB DEPRESSED (FAST):
-500 FT/MIN
BEFORE LANDING TO AVOID A CABIN PRESSURE BUMP AT TOUCH DOWN, THE CABIN
ALTITUDE IS AUTOMATICALLY MAINTAINED AT 300 FT BELOW:
SELECTED LANDING ELEVATION
AFTER LANDING THE CABIN PRESSURISATION RATE IS:
+550 FT/MIN
IN CASE OF “ADC 1” FAILURE, THE DIGITAL CONTROLLER USES AS REFERENCE AIRCRAFT
STATIC AIR PRESSURE GENERATED BY:
ADC 2 AND 1013 HPA
WHAT IS THE CORRECT WAY TO SWITCH FROM AUTOMATIC TO MANUAL OPERATION?
TURN THE CABIN PRESS RATE KNOB TO 9 O’ CLOCK POSITION, SELECT CABIN PRESS PB
AND OPERATE THE MAN RATE KNOB AS REQUIRED
IN “MAN MODE” WHAT IS THE HIGHEST CABIN RATE OF DESCENT AND CLIMB AVAILABLE:
-1500FT/MIN; +2500 FT/MIN
WHAT IS THE CORRECT WAY TO SWITCH FROM MANUAL TO AUTOMATIC OPERATION?
SELECT MODE SELECT PB TO AUTO AND TURN THE MAN RATE KNOB SMOOTHLY TO
NORMAL POSITION
WHAT HAPPENS IN CASE OF LOSS OF ELECTRICAL SUPPLY TO THE “DIGITAL CONTROLLER” IN
AUTOMATIC MODE:
BOTH OUTFLOW VALVES GO TO FULL CLOSE
IN CASE OF TOTAL DC ELECTRICAL POWER LOSS:
AUTO PRESS MODE IS LOST
MANUAL PRESS MODE AND CABIN PRESS INDICATIONS ARE STILL AVAILABLE
THE FWS IS ACTIVATED WHEN THE CABIN ALTITUDE REACHES:
10 000 FT
WHEN IS THE “DUMP” FUNCTION AVAILABLE:
IT ONLY WORKS IN AUTO PRESS MODE
HOW MANY OUTFLOW VALVES ARE OPENED IN “DUMP” FUNCTION?
THE PNEUMATIC VALVE
&THE ELECTRO-PNEUMATIC VALVE
SELECTING THE “DITCH MODE” WITH THE “DITCH PB”:
TWO ELECTRICAL MOTORS MAINTAIN BOTH OUTFLOW VALVES IN CLOSED POSITION,
REGARDLESS OF AUTO OR MANUAL PRESS MODE USE
IN ADDITION TO THE WHITE LIGHT ON DITCH PB, MASTER CAUTION FLASHES AMBER
AND AIR AMBER LIGHT ILLUMINATES ON FWS
