Page 11
Section - 2
LIMITATIONS
FAA Approved
Original Issue: Feb 28, 2006
Hawker 850XP Pro Line 21 Airplane Flight Manual
ICE PROTECTION LIMITATIONS
Icing General
Icing conditions exist when Outside Air Temperature (OAT) on the ground and during takeoff,
is 10
°
C SAT or below, and visible moisture in any form is present (e.g. clouds, fog with visibility
of 1 mile (1600 meters) or less, rain, snow, sleet and ice crystals).
Icing conditions also exist when the OAT on the ground and for takeoff is 10
°
C or below when
operating on ramps, taxiways, or runways where surface snow, ice, standing water or slush may
be ingested by the engines or freeze on the engines, nacelles or engine sensor probes.
Airframe Icing
Takeoff is prohibited with frost, ice, snow or slush adhering to the wings, control surfaces,
engine inlets or other critical surfaces, with the exception of the following areas:
• Frost is allowable on the underside of the wings over the general area of the fuel tanks
provided that the depth does not exceed 1/8 inch (3 mm).
If frost is present in this region, the WAT limited take-off weight must be reduced by 1000
lb (454 kg) and the net flight path reference and fourth segment climb gradients must be
obtained using a weight 1000 lb (454 kg) higher than the actual weight.
• Frost is allowable on the fuselage provided the layer is thin enough to distinguish the
surface features such as paint lines or markings underneath, but all vents, probes and
ports must be clear of frost.
A visual and tactile (hand on surface) check of the wing leading edges and the wing upper
surface must be performed to ensure the wing is free from frost, ice, snow or slush when the
outside air temperature is less than 50° F (10° C) or if it cannot be ascertained that the wing
fuel temperature is above 32° F (0° C) and;
• There is visible moisture (rain, drizzle, sleet, snow, fog, etc.) present;
or
• Water is present on the wing;
or
• The difference between the dew point and the outside air temperature is 5° F (3° C) or less;
or
• The atmospheric conditions have been conducive to frost formation.
Wing/Tail Antice System
Only de-ice fluids TKS80, R328 or fluid to specification DTD 406B must be used.
NOTE: A tank indicating FULL provides priming and protection for a period of at least
85 minutes.
Engine Icing
Refer to ENGINE LIMITATIONS - this section.
For Training Purposes Only
