ATR SYSTEMS

Question 1

MFC

Answer 1

MULTI FUNCTION COMPUTER
Two independent computers each include two independent modules.
Purpose= Monitor,control,authorise operation of the aircraft systems.
Manage system failures and flight envelope anomalies and command triggering of associated warnings.

Question 2

CCAS

Answer 2

CENTRALIZED CREW ALERTING SYSTEM
Purpose= To draw crews attention when a failure is detected and guides the crew to the system affected by the failure.
THREE TYPES OF VISUAL DIVICES USED
-Master warning and master caution lights
-Crew alerting panel CAP
-Local alert lights

Question 3

AFCS

Answer 3

AUTOMATIC FLIGHT CONTROL SYSTEM
Receives data from the two ADC,AHRS,SGU, the radio altimeter,the GNSS and some sensors. It generates commands to the flight control actuators/servos and to the FD bars.

Question 4

ADU

Answer 4

ADVISORY DISPLAY UNIT

Displays; Advisories, selected modes, messages, armed modes and captured modes.

Question 5

EFIS

Answer 5

ELECTRONIC FLIGHT INSTUMENT SYSTEM

Control panel to set nav, brg arc and map on the EHSI

Question 6

EGPWS

Answer 6

ENHANCED GROUND PROXIMITY WARNING SYSTEM
Provides visual and aural alerts in case of dangerous flight path conditions which would result in inadvertent ground contact if maintained.
Alert modes;
1 EXCESSIVE DECENT RATE
2 EXCESSIVE TERRAIN CLOSURE RATE
3 ALTITUDE LOSS AFTER TAKE OFF
4 UNSAFE TERAIN CLEARENCE 
5 BELOW GLIDESLOPE
6 ALTITUDE CALLOUTS
Enhanced modes:
TERRAIN CLEARANCE FLOOR TCF
TERRAIN AWARENESS & DISPLAY TAD

Question 7

MCDU

Answer 7

MULTIFUNCTION CONTROL DISPLAY UNIT
Is the interface between pilot and HT1000.
It is used to enter, monitor and revise routes

Question 8

NPU

Answer 8

NAVIGATION PROCESSOR UNIT
Receives and processes the GNS/FMS signal data from the GPS antenna and other aircraft systems i.e Air Data Computer to compute position and course info. It transmits data to the MCDU for display and to other aircraft systems such as autopilot, HSI and CDI.

Question 9

AHRU

Answer 9

ATTITUDE AND HEADING REFERENCE UNIT
Includes an internal measurement unit composed of three gyro meters and three accelerometers. The AHRU receives inputs from its associated flux valve and the TAS, fed by both ADC, is used to compute gyro erection

Question 10

ADC

Answer 10

AIR DATA COMPUTERS
Is supplied with static air pressure, total pressure (Pitot ports) total air temp (TAT probes). with these inputs the ADC computes pressure altitude,VS,IAS,TAS,TAT,SAT.

Question 11

SGU

Answer 11

SYMBOLS GENERATOR UNIT

Collects data from AFCS,AHRU,ADC,VOR,ILS,DME,ADF, GNSS,CRS and HDG. Converts the data into video format for EADI,EHSI

Question 12

TLU

Answer 12

TRAVEL LIMITING UNIT
Limits rudder travel is done through ADC 1/2 when reaching speed 185 kts when accelerating and disengaged when reaching 180 knots when decelerating.

Question 13

TRU

Answer 13

TRANSFORMER RECTIFIER UNIT

Question 14

HMU

Answer 14

HYDROMECHANICAL UNIT

Question 15

BTC

Answer 15

BUS TIE CONTACTOR

Question 16

ATPCS

Answer 16

AUTOMATIC TAKE OFF POWER CONTROL SYSTEM
It provides in case of an engine failure during take off the untrimmed take off power on the remaining engine combined with an automatic feathering on the failed engine.
Arming conditions:
PWR MGT SELECTOR TO
ATPCS PB ON
BOTH PL 49'
BOTH TORQUE ABOVE 46%
AIRCRAFT ON THE GROUND
= uptrim and auto feather
same conditions for in flight however there is no uptrim

Question 17

ETOPS

Answer 17

EXTENDED TWIN OPERATIONS

Question 18

PEC

Answer 18

PROPELLER ELECTRONIC CONTROL
Is a dual channel electronic box which provides closed loop control over the propeller pitch change system.The PEC detects, isolates and accommodates system faults.

Question 19

TAWS

Answer 19

TERRAIN AWARENESS WARNING SYSTEM