135.227 Icing conditions: Operating limitations.
(a) No pilot may take off an aircraft that has frost, ice, or snow
adhering to any rotor blade, propeller, windshield, wing, stabilizing or
control surface, to a powerplant installation, or to an airspeed, altimeter,
rate of climb, or flight attitude instrument system, except under the
following conditions:
(1) Takeoffs may be made with frost adhering to the wings, or stabilizing
or control surfaces, if the frost has been polished to make it smooth.
(2) Takeoffs may be made with frost under the wing in the area of the
fuel tanks if authorized by the Administrator.
(b) No certificate holder may authorize an airplane to take off and no
pilot may take off an airplane any time conditions are such that frost, ice,
or snow may reasonably be expected to adhere to the airplane unless the
pilot has completed all applicable training as required by §135.341 and
unless one of the following requirements is met:
(1) A pretakeoff contamination check, that has been established by the
certificate holder and approved by the Administrator for the specific
airplane type, has been completed within 5 minutes prior to beginning
takeoff. A pretakeoff contamination check is a check to make sure the wings
and control surfaces are free of frost, ice, or snow.
(2) The certificate holder has an approved alternative procedure and
under that procedure the airplane is determined to be free of frost, ice, or
snow.
(3) The certificate holder has an approved deicing/anti-icing program
that complies with §121.629(c) of this chapter and the takeoff complies with
that program.
(c) Except for an airplane that has ice protection provisions that meet
section 34 of appendix A, or those for transport category airplane type
certification, no pilot may fly—
(1) Under IFR into known or forecast light or moderate icing conditions;
or
(2) Under VFR into known light or moderate icing conditions; unless the
aircraft has functioning deicing or anti-icing equipment protecting each
rotor blade, propeller, windshield, wing, stabilizing or control surface,
and each airspeed, altimeter, rate of climb, or flight attitude instrument
system.
(d) No pilot may fly a helicopter under IFR into known or forecast icing
conditions or under VFR into known icing conditions unless it has been type
certificated and appropriately equipped for operations in icing conditions.
(e) Except for an airplane that has ice protection provisions that meet
section 34 of appendix A, or those for transport category airplane type
certification, no pilot may fly an aircraft into known or forecast severe
icing conditions.
(f) If current weather reports and briefing information relied upon by
the pilot in command indicate that the forecast icing condition that would
otherwise prohibit the flight will not be encountered during the flight
because of changed weather conditions since the forecast, the restrictions
in paragraphs (c), (d), and (e) of this section based on forecast conditions
do not apply