Mod. : 1742
ATR 42 Model : 400/500
ENGINE AND WING PROTECTION
ICE AND RAIN PROTECTION
P 3
NOV 97
030
1.13
.
30
30.2 CONTROLS
ENGINE ANTI-ICING AND WING DE ICING PANEL
AIRFRAME AIR BLEED pb
Controls both de ice and isolation valves.
Pb pressed in Normal operation.
Both DE ICE and ISOLATION VALVES are open.
OFF
(pb released) OFF light comes on white.
Both DE ICE and isolation valves are closed.
However engine anti-icing may be used (engine anti-icing selected ON
will open de-ice valve).
But airframe de-icing is never available.
FAULT The light illuminates amber and the CCAS is activated when :
- Air pressure downstream of the de-ice valves stays below 14 PSI for
more than 10 seconds.
- Inflation sequencing of airframe boots A or B is not correct.
- Air temperature upstream of the de-ice valves exceeds 230
°
C.
The alert is inhibited when pb is released.
AIRFRAME pb
Controls the outputs A and B of both wings and stabilizers distribution valves.
ON
(pb pressed in) Signal is sent to the MFC in order to initiate a
de-icing cycle depending on MODE SEL pb.
ON light illuminates blue.
Pb released Pb released. In normal operation. Associated boots stay deflated.
FAULT
The light illuminates amber and the CCAS is activated when :
- Associated distribution valve output has been controlled open but
no downstream pressure has been detected, or
- Associated distribution valve output has been controlled closed
but a downstream pressure is detected.
AA
1
2
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