C. Telescopic Duct
(Ref. Fig. 008)
The telescopic duct is at track 7. It connects the lagged anti-ice duct
(on the front spar) to the piccolo duct in slat 3.
The telescopic duct has three sliding tubes with (ball type) couplings at each end. The sliding tubes decrease (in internal diameter) from 73.66 mm
(2.9 in.) at the fixed leading-edge duct to 57.15 mm (2.25 in.) at the slat.
D. Piccolo Ducts
(Ref. Fig. 001)
Three piccolo ducts are in each wing, one in each of the slats 3, 4 and
5. Each piccolo duct has three rows of holes that face the leading-edge skin of the slat. The holes release the hot air on to the inner surface of the slat leading-edge skin.
The piccolo duct in the slat 3 has a diameter of 63.5 mm (2.5 in.) and decreases in size to 44 mm (1.73 in.) at the outboard end of the slat 5.
E. Flexible (interconnecting) Ducts
The flexible ducts connect the piccolo ducts in the slats 3, 4 and 5. The flexible ducts are made of a high-tensile support-wire with a glass-silicone fabric cover.
7. Operation/Control and Indicating________________________________
The wing ice protection system starts when the ANTI ICE pushbutton switch (P/BSW) is operated. The switch is on the overhead control panel 25VU, in the cockpit.
The pneumatic system usually takes its supply of air from the engine intermediate pressure (IP) bleed. If the engine operates at low RPM, or the bleed air temperature is too low, the supply changes to the engine high pressure (HP) bleed. The pneumatic system makes this change-over automatically and supplies air to the wing ice protection system at the correct temperature. The wing anti-ice control valve keeps the air at the correct pressure.
A. Operation Logic
If one of the engines does not supply bleed air (because of a failure), the cross-bleed valve opens to let air go to the LH and the RH wing. In this configuration, the airflow in the system decreases.
1EFF : ALL 1 30-11-00Page 16 1 1 May 01/04R 1 1 1CES 1
Telescopic Duct - Component Location Figure 008
1EFF : 1 1R 1CES ALL 1 11 1 30-11-00 Page 17 May 01/04
If a failure of the wing anti-ice control valve(s) occurs on the ground, it is possible to manually lock it/them in the OPEN or CLOSED position.
NOTE : The RH anti-ice control valve may be locked in the OPEN position,
____ but the correct ECAM procedure must be applied (REF. 30-11-00-04). When the valve(s) is/are locked in the CLOSED position, the aircraft is not permitted to fly into icing conditions.
The limits of the wing ice protection system are:
Supply Pressure 1.33 to 1.67 bar (20 to 25 psi)
Supply Temperature 185 to 215 deg. C. (365 to 419 deg. F)
Mass Flow Through Valve 0.327 kg/s (0.7 lb/s)
at 22,000 ft.
B. Controls and Indications
(Ref. Fig. 002, 009)
The wing ice protection system is energized by the pushbutton switch (P/BSW) 3DL on the cockpit overhead panel 25VU. The P/BSW (3DL) has two illuminated conditions:
-FAULT : amber
-ON : blue.
The procedure to operate the anti-ice system on the ground is the same as in flight. But on the ground the relay 4DL (ground test) supplies the ground to the relay 5DL. For safety, the relay 4DL also limits the system operation time to 30 seconds.
The FAULT light comes on (amber) if:
-
the left valve air outlet pressure is low
-
the right valve air outlet pressure is low
-
the left and/or the right valve fails to close
-
the left and/or the right valve fails to open
-
the control relay (5DL) does not operate
中國航空網 m.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：A320飛機維護手冊 AMM ICE AND RAIN PROTECTION 防冰和排雨1(24)
