Specifications

SECTION II
AIRPLANE AND SYSTEMS
MODEL 560
NOTE
f Icing conditions exist when the indicated RAT on the ground and for takeoff is +10°C
(+50°F) or below; the indicated RAT inflight is +10°C (+50°F) or below; and visible
moisture in any form is present (such as clouds, fog with visibility of one mile or less,
rain, snow, sleet or ice crystals).
f Icing conditions also exist when the indicated RAT on the ground and for takeoff is
+10°C (+50°F) or below when operating on ramps, taxiways or runways where
snow, ice, standing water, or slush may be ingested by the engines or freeze on
engine nacelles or engine sensor probes.
ENGINE AND WING ANTI-ICE SYSTEM
Bleed air flows continuously through the fan spinner whether the anti-ice system is activated or not.
When the wing/engine anti-ice switches (one for each engine) are positioned to ENGINE ON, bleed air flows
through the applicable engine inlet and engine stators. Adequate bleed air flow is available to maintain the
proper engine inlet temperatures at flight idle thrust. The engine anti-ice annunciators may illuminate initially
when the system is turned on if the inlets are cold. When the wing/engine anti-ice switches are positioned
to WING/ENGINE ON, bleed air flows to the wing leading edges in addition to the engine inlet ring. If
sufficient bleed air flow is not available to maintain the proper wing temperature, the wing anti-ice
annunciator will illuminate. The light may be extinguished by increasing engine RPM. Operation of the
system may be checked by observing engine ITT rise when the wing/engine anti-ice switches are turned
on. If the check is made on the ground, it may require up to two minutes to extinguish the wing anti-ice
light with N
1
set at approximately 70%. Maximum engine power setting values are reduced when using
anti-ice, as shown in Section IV.
Loss of electrical power to the valve supplying flow to the inlets results in the anti-ice valves opening,
thus assuring anti-ice capability. The WING XFLOW switch is designed to provide wing anti-ice protection
to both wings in the event of an inoperative engine. The over-temperature and under-temperature sensors
of both wings shall be active during WING XFLOW operations. During WING XFLOW operations, the anti-
ice switch of the inoperative engine should be selected OFF to prevent illumination of the ENG ANTI-ICE
annunciator.
The wing and engine anti-ice systems may be checked on preflight by selecting both systems ON with
the engines at idle. A very small increase in ITT and very small drop in N
2
signifies that bleed flow has
occurred. The WING ANTI-ICE L-R will illuminate initially to indicate an under temperature condition on the
wing leading edges. The ENG ANTI-ICE L-R may not illuminate initially if the ambient temperature is above
15°C.
CAUTION
DURING SUSTAINED GROUND OPERATIONS IN FREEZING PRECIPITATION, IF
THE ENGINES ARE OPERATED AT IDLE, ICE MAY FORM ON ENGINE PROBES
AND INTERNAL COMPONENTS. THIS MAY CAUSE ENGINE VIBRATION. BY
INCREASING THE ENGINE SPEED TO 60% N
2
OR HIGHER, THE ENGINE
VIBRATION WILL BE ELIMINATED.
NOTE
During sustained ground operations in freezing precipitation, the engines should be
operated for one minute out of every 4 minutes at 65% N
2
or above to preclude ice
forming on engine probes or internal components.
I 2-46 Configuration AA 56OMB-01