5-30B. ICING LIMITATIONS (SEVERE).
Severe icing may result from environmental
conditions outside of those for which the
airplane is certificated. Flight in freezing
rain, freezing drizzle, or mired icing
conditions (supercooled liquid water and ice
crystals) may result in a build-up on
protective surfaces exceeding the capability of
the ice protection system, or may result in ice
forming aft of these protected surfaces. This
ice may not shed using ice protection systems,
and may seriously degrade the performance
and controllability of the airplane.
a During flight, severe icing conditions that exceed
those for which the airplane is certificated shall be
determined by the following visual cues. If one or more of
these visual cues exists, immediately request priority
handling from air traffic control to facilitate a route or an
altitude change to exit the icing conditions:
(1) Unusually extensive ice accreted on the
airframe in areas not normally observed to collect ice.
(2) Accumulation of ice on the upper (or lower, as
appropriate) surface of the wing aft of the protected area.
(3) Accumulation of ice on the propeller spinner
farther aft than normally observed.
b. Since the autopilot may mask tactile cues that
indicate adverse changes in handling characteristics, use of
the autopilot is prohibited when any of the visual cues
specified above exist, or when unusual lateral trim
requirements or autopilot trim warnings are encountered
while the airplane is in icing conditions.
All icing detection lights must be operative prior
to flight into icing conditions at night. This
supersedes any relief provided by the master
minimum equipment list (MMEL) or equivalent.
5-31. CROSSWIND LIMITATIONS.
The maximum crosswind component is 17 knots at 90o.
The maximum angle of bank in a slip during landing is 8o.
Landing the aircraft in a crab will impose side loads on the
landing gear and should be recorded on the DA Form 2408-
13-1. Refer to Chapter 8 for crosswind landing technique.
5-32. OXYGEN REQUIREMENTS.
For oxygen requirements applicable to the RC-12G
aircraft, see AR 95-1.
5-33. CABIN PRESSURE LIMITS.
Maximum cabin differential pressure is 6.1 PSI.
5-34. CRACKED CABIN WINDOW / WIND-
If a crack occurs in both the inner and outer plys of a
cabin window, the aircraft cannot he flown, except to be
ferried to a maintenance facility for replacement of the
If a crack occurs in either layer of a cabin window, the
aircraft can only he flown in an unpressurized flight.
For further information on cracked cabin
window procedures, see Service Instruction No.
If there is a crack in only the outer ply of the
windshield, unpressurized flight may be conducted
provided that the following procedures and restrictions are
1. Cracking must not significantly impair visibility of
objects outside the aircraft.
2. Cracking must not interfere with the use of the
3. The heating elements must be operative.
If there is a crack in the inner ply of the windshield, the
windshield must be replaced prior to the next flight, to
prevent injury to the pilots from possible glass splinters.