Deice

Question 1

De-ice Master

Answer 1

When ON, with ENG ANTI-ICE , WINDSHIELD ANTI-ICE and BLADE DEICE POWER switches OFF, automatically turns these systems on when ice accumulation detected by sensor (if any individual systems already on, disables auto function and runs continuously)

OFF disables automatic function

Question 2

Rotor Blade De-ice

Answer 2

Provides controlled electrical power to integral heating elements in the main and tail rotor blades allowing symmetrical ice shedding

Question 3

Ice Detector

Answer 3

Senses ice accumulation on a vibrating probe by measuring change in probe frequency–triggers ICE DETECTED

Simultaneously, aspirator heater on the probe is turned on to heat the probe, shed the ice and reset it for another cycle

Severity of icing is proportional to rate at which the probe heater is cycled

Question 4

MODE Selector AUTO Operation

Answer 4

OAT sensor provides signal to controller to govern heating EOT; the lower the OAT, the longer EOT will be

Ice-rate signal produces heating element off-time

Question 5

Deice Cycles

Answer 5

Used to reduce power requirements (not on tail rotor, all at same time)

Question 6

Droop Stop Heaters

Answer 6

Continuously heated as long as the BLADE DEICE control panel power switch is in the POWER ON or TEST position

Question 7

MANUAL L, T, M Operation

Answer 7

Results in fixed off-time based on setting

Should be selected when an icing rate system malfunction is indicated by ICE DETECT FAIL or when there is no indication of failure, but any of these has occurred:
1. Pilot has determined by judgement of icing intensity that ice rate system is inaccurate

2. Torque has increased to an unacceptable level
3. Helo vibes increased to unacceptable level

Question 8

Windshield Anti-ice

Answer 8

Each windshield has own system operated by switch on upper console

WARNING
A faulty windshield anti-ice system could result in arcing and delamination of the windshield. If not secured in a timely manner, an electrical fire could result

Question 9

Pitot Heat

Answer 9

Shall be turned on when OAT <5*C or when visible moisture is present. Failure to turn on pitot heat in icing conditions may cause erroneous airspeed indications which can lead to erratic and/or downward programming of the stabilator and loss of control of the aircraft