Ice And Rain

Question 1

What is ice and rain protection

Answer 1

The ice and rain protection system consists of an ice detection system, wing anti-ice system, cowl anti-ice system, windshield and side window antiice system and the air data probes and sensors heating system. The ice and rain protection system protects against ice accumulation on flight-critical aircraft surfaces. The ice detection system provides the flight crew with indication of icing conditions. It can automatically turn on the wing and cowl anti-icing systems if icing is detected. The wings and engine nacelles (cowls) are antiiced, using hot engine bleed air from the pneumatic system. Two bleed management controllers (BMCs) control and monitor wing anti-ice operation. The BMCs also monitor cowl anti-ice operation. The windshields and side windows are heated electrically. They are controlled by two (left and right) controllers. The air data sensor system probes and sensors are heated electrically. Two heater/brake temperature monitoring units (HBMUs) control and monitor the air data sensor heating system. The HBMU also controls yaw damper heating and monitors brake temperature.

Question 2

Does apu supply anti ice air

Answer 2

No

Question 3

What is HBMU

Answer 3

HEATER BRAKE MONITORING UNIT

Question 4

Where are ice temp sensors

Answer 4

It’d and obd of wings, 2 each

Question 5

What is wai indication on EICAS

Answer 5

WAI indicated on engine itt display

Question 6

What does ice detection consist of

Answer 6

The ice detection system consists of two ice detectors and two bleed management controllers (BMCs). The ice detection system determines when the aircraft is in icing conditions and provides warnings to the pilots. It will also provide activation of wing and cowl anti-icing systems if system is set to auto mode. Ice accumulation on the probes causes a change in vibration frequency and the probe sends ice signals to automatically activate wing anti-ice (through the BMCs), and to automatically activate cowl anti-ice (via relays). After ice is detected, the probes are heated to shed the ice so the probes can again detect the icing conditions.

Question 7

What is the BMC

Answer 7

Bleed management controller

Question 8

What is ice detector

Answer 8

One ice detector is installed on each side of the aircraft below the side window panels. Each ice detector has a probe. The probe is a tube installed in a strut, which also includes a magnet, a drive coil and a pickup coil. The drive coil is installed around the lower half of the tube. A strut heater and a probe heater are installed in the head of the ice detector body. The ice detector probe uses magnetic properties for analysis of the icing conditions.50hz and 51hz

Question 9

What bus l/h ice detector

Answer 9

115ac ess bus,
R/h ice detector 115 ac bus 1

Question 10

What is power on built in test

Answer 10

One ice detector is installed on each side of the aircraft below the side window panels. Each ice detector has a probe. The probe is a tube installed in a strut, which also includes a magnet, a drive coil and a pickup coil. The drive coil is installed around the lower half of the tube. A strut heater and a probe heater are installed in the head of the ice detector body. The ice detector probe uses magnetic properties for analysis of the icing conditions.

Question 11

What is ice test

Answer 11

The detection system continuously monitors the actual condition of the two ice detectors to prevent transmission of incorrect data on icing condition to the bleed management system. During each program cycle the frequency is measured and compared to the normal operating frequency (40,000 Hz). If the frequency is above 40,150 Hz, a failure output is generated. If the frequency falls 130 Hz the ice detector goes through a normal icing cycle. After the heater has tried to melt the ice unsuccessfully for 10 seconds and the frequency is still below 39,870 Hz, the heater and ice output are turned off, the failure signal is activated and the failure is logged in RAM.

Every 60 seconds a comprehensive test is performed on the ice detector circuitry. The heater is tested by pulsing it on for 400 ms. The failure and icing signal outputs are also pulsed to verify each state. This test also verifies proper operation of the microcomputer. If a failure is detected, the BMCs generate a CAIMS fault and a CAS message.

Question 12

Wing anti ice uses what air

Answer 12

Direct uncooled bleed air

Question 13

Engine bleed op

Answer 13

Low pax feeds cowl anti ice, hight pax supplies respective wing through PRV, wing AI valve regulates wing l/e temp

Question 14

Anti ice valve in auto

Answer 14

Controlled by BMC,S

Question 15

How many wing anti ice valves

Answer 15

2, 1 for each wing

Question 16

What is fail safe closed

Answer 16

Wing anti ice sensor,
Intake cowl fails open

Question 17

What is; WAITS

Answer 17

Wing temp anti ice sensor

Question 18

What stage does cowl anti ice use

Answer 18

5th stage,lp, controlled by cowl anti ice valve, via hp air to close valve

The valve will open under spring force when the duct is unpressurized. When the solenoid is energized and there is sufficient duct pressure the valve will close. Upstream air pressure to operate the valve is tapped off from the 8th-stage bleed port.

To open the valve the solenoid is deenergized. The valve will pressure regulate to 25 + 3 psi.

Question 19

What stage is wing anti ice

Answer 19

8th stage

Question 20

Dont forget hole on cowl anti ice press to

Answer 20

The cowl anti-ice pressure transducer is installed on the inlet cowl rear bulkhead. It measures, through a pneumatic sense line, the air pressure downstream of the cowl anti-ice valve and supplies the information to the bleed management controller to produce the flow tube indications and system status on the bleed/anti-ice synoptic page.

Question 21

How many heater elements per window

Answer 21

3

Question 22

What windows are heated

Answer 22

The windshield and side window anti-ice system consists of windshield and side window heating elements, temperature sensors and windshield temperature controllers (WTCs). The aircraft windshields and side windows have heating elements to prevent icing, misting or fogging. The heaters are between the faceply and

outer acrylic ply of the windshields and between the two acrylic plies of the side windows. Two temperature controllers independently control the power of the heaters in the left and right windshields and side windows. The temperature controllers monitor temperature sensors installed in the windshields and side windows to control the heat. The controllers are controlled from the windshield heat panel on the cockpit overhead panel.

Question 23

Where is cockpit window heat panel

Answer 23

Overhead above F/O

Question 24

Where are windshield controllers

Answer 24

1 each behind pilots, 2 off

Question 25

What is warmup mode

Answer 25

Warmup Mode
A warmup mode is available on the front windshields only. This mode is provided to avoid the effect of thermal shock on the windshields during power on application. The warmup mode is activated when the windshield heat switch is selected ON and the following conditions apply: Power has been off the windshields for more than 3 to 7 seconds. AND The aircraft is on the ground (weight on wheels). During the warmup mode the windshield heating element operates at 33% of nominal heat, being powered from one phase to neutral (ground) instead of two phase (200 VAC) as it is in normal regulating mode. The warmup mode lasts for a period of 4 minutes.

Question 26

What is tat 3 connected to

Answer 26

Tat 3 is connected to HBMU 1

Question 27

What happens when ac power is put on aircraft

Answer 27

Full powered bite test- heaters etc

Question 28

Are yaw dampers heated

Answer 28

XRS = YES
5000 NO