After the ice vanes have been manually
extended, they may be mechanically re-
tracted. No electrical extension or retrac-
tion shall be attempted as damage to the
electric actuator may result. Linkage in
the nacelle area must be reset prior to op-
eration of the electric system. Do not re-
set ice vane control circuit breaker.
1.
Airspeed - 160 KIAS or below.
2.
Ice vane control circuit breaker - Pull.
3.
Ice vane - Operate manually.
masks - 100% and on.
4.
Airspeed - Resume normal airspeed.
DO NOT RETRACT ice vanes electrical-
ly after manual extension.
9-18. ENGINE BLEED AIR SYSTEM MALFUNC-
TION.
a. Bleed Air Failure Light Illuminated. Steady
illumination of the warning light in flight indicates
a possible ruptured bleed air line aft of the engine
firewall. The light will remain illuminated for the re-
mainder of flight. Perform the following:
N O T E
BLEED AIR FAIL lights may momentari-
ly illuminate during simultaneous surface
deice and brake deice operation at low
N1. speeds.
1.
Brake deice switch - OFF.
2.
TGT and torque - Monitor (note read-
ings).
3.
Bleed air valve switch - PNEU & EN-
VIRO OFF.
N O T E
Brake deice on the affected side, and rud-
der boost, will not be available with
BLEED AIR VALVE switch in PNEU &
ENVIRO OFF.
4.
Cabin pressurization - Check.
b. Excessive Differential Pressure. If cabin dif-
ferential pressure exceeds 6.1 PSI, perform the fol-
lowing:
1.
2.
3.
4.
5.
6.
7.
Cabin controller - Select higher setting.
If condition persists: Left bleed air
valve switch - ENVIRO OFF flight illu-
minated).
If condition still persists: Right bleed
air valve switch - ENVIRO OFF (light
illuminated).
If condition still persists - Descend im-
mediately.
If
unable
to
descend:
Crew
oxygen
If unable to descend: CABIN PRESS
switch - DUMP.
Bleed air valve switches - OPEN, if
cabin heating is required.
9-19. LOSS OF PRESSURIZATION (ABOVE 10,
000 FEET).
If cabin pressurization is lost when operating
above 10,000 feet or the ALTITUDE warning light
illuminates, perform the following:
1. Crew oxygen masks - 100% and on.
9-20. CABIN DOOR CAUTION LIGHT ILLUMINAT-
ED.
Remain clear of cabin door and perform the fol-
lowing:
1.
Bleed air valve switches - ENVIRO OFF.
2.
Descend below 14,000 feet as soon as practi-
cable.
3.
Oxygen - As required.
9-21. SINGLE-ENGINE DESCENT/ARRIVAL.
N O T E
Approximately 85% N1 is required to
maintain pressurization schedule.
Perform the following procedure prior to the fi-
nal descent for landing.
1. Cabin controller - Set.
2. Seat belts and harnesses - Secure.
TM 55-1510-219-10
9 - 7