6 - Indicating And Warning Systems

Question 1

Describe the architecture for the EC175 alerting system:

Answer 1

Input. Ancillaries. Output.

Vehicle & Eng. Data. —————— LH ASU. RH ASU.
LG / RH Pitot. ————————— LG AU.
Land. Light / LH & Emerg Pitot. —- LL AU. ——- AMC1 & AMC2
Integrated Lighting. ——————- LAU1. LAU2.

• Relay cards (2 x front, 1 x rear) are controlled by various items
• Diode cards are used for power supplies

Question 2

What ancillary units are on the EC175, and where are they located?

Answer 2

Landing Light Ancillary Unit (LL AU) (front RH relay cards). Nose bay, upper left
Landing Gear Ancillary Unit (LG AU) (front LH relay cards). Nose bay, upper right
Lighting Ancillary Unit 2 (LAU2) (front diodes cards). Nose bay, lower left
Lighting Ancillary Unit 1 (LAU1) (front diodes cards). Nose bay, lower right

Question 3

What are the four main stages of Alerting, and the hierarchy on the Master List?

Answer 3

Warning (Red). Major system failure. Unique tone OR Tone + Voice
Caution (Amber). System failure or degrade. Generic tone
Advisory (White). Clearance Test/Inflight trend. None
Information (Green). Expected configuration. None

• Alert ACK can be achieved through FND MFD ACK button or MASTER ACK on cyclic (preferred)
• Maximum 7 messages on screen before scroll option (through rotary knob)
• Review last message by ‘press and hold’ FND MFD ACK button.

Question 4

What methods of alerting are on the EC175?

Answer 4

MFD Master List
- Alert ACK can be achieved through FND MFD ACK button or MASTER ACK on cyclic (preferred)
- Maximum 7 messages on screen before scroll option (through rotary knob)
- Review last message by ‘press and hold’ FND MFD ACK button
Audio
CWP (Central Warning Panel

Question 5

Which systems are tested through ‘Lamp Test’?

Answer 5

Audio. CWP.
LG (Landing Gear) Transit Light. Floatation.
ECS Panel. ICS Panels.
Fire Extinguisher. Engine Control.
Hydraulic Bypass. Electrical EPU.
ELT (Emerg. Location Xmitter)

Question 6

What is the Usage Monitoring System (UMS)?

Answer 6

• Records ac parameters via VMS Partition
• Functions inc:
  
  • Auto counting (Flt time/LG cycles/Eng cycles/MGB Tq cycles/NR cycles/Chip detection)
  • Exceedances (Eng Temps/N1/N2/Tq/Fuel Temp & Px/NR/MGB Tq)
  • Engine Power Check (EPC)
  • Post-flight data download to the DTD Compact Flash
  • Data displayed on MFD4 (VMS Main)

Question 7

What is the UMS Timeline of operation?

Answer 7

Power on. AMC ON, VMS/UMS operational (ready, NOT recording)
1st Engine Start. UMS recording
Take Off
Landing. UMS manual D/L possible (Rotors running)
NR <10%. UMS session stops recording
Rotors stopped. AMC VMS/UMS off

Question 8

What triggers ‘DATA CARD’ Advisory message?

Answer 8

• no card present
• DTD door open
• Compact Flash card is unreadable (gravy!)

Question 9

What triggers ‘DATA CARD FULL’ Advisory message?

Answer 9

• insufficient space on card for next flight
  (Only displayed on ground)

Question 10

What triggers ‘FLIGHT REPORT EVENT’ Advisory message?

Answer 10

• UMS has logged an in-flight checkable exceedance
• can be: Eng (N1/N2/TOT) or Vehicle (Tq/NR/Mast moment/Chip) over-limit
• message will be present on next power up; only clear when ac next starts

Question 11

What is the Health Monitoring System (HMS)?

Answer 11

2 Functions:
- monitors all rotating parts of the drive chain
- Rotor Track and Balance (RTB)

Question 12

How does the HMS work?

Answer 12

Components:
- Dynamic Monitoring Acq. Unit (DMAU); 12 x accelerometers; MR & TR sensors

Principle:
- ‘Learns’ what is normal for components; alerts if threshold breached
- Thresholds can be moved (following investigation)
- If components replaced, next flight will generate a Red alert.