AIR Flight Training focuses on detailed, scenario-based Piper PA-46 training for Malibu, Mirage, Matrix, and Meridian pilots. We arm pilots with the knowledge and experience to react in any situation.


Winter is upon us, which means so are freezing temperatures, snow, and ice. As we know, this season brings increased precautions for pilots in areas including: deicing, anti-icing, cold weather maintenance, and flight operations. While the increased precautions can be tedious and annoying, it’s crucial to be aware of the necessary steps to uphold regulation and safety. For example, not properly checking the fuel tanks for water contamination could lead to an engine failure in-flight, if the water freezes and blocks fuel flow.

In Boeing’s Safe Winter Operations article, the Clean-Airplane concept is explained, which is useful for remembering the regulatory nature of winter operations. FAR 121.629 states, “No person may take off an aircraft when frost, ice or snow is adhering to the wings, control surfaces, propellers, engine inlets, or other critical surfaces of the aircraft or when the takeoff would not be in compliance with paragraph (c) of this section.” Accordingly, the Clean-Airplane concept describes an aircraft that is free of frost, ice, or snow. We learned in primary training that such contaminants adhered to an airplane, especially  the wings and control surfaces, reduces lift, increases drag, increases stall speed, and creates a much heavier airplane. Thus, it is important to remember and conform to this concept. Per the PA-46-500TP Meridian PO, takeoff is prohibited with the following forms of contamination:

With frost adhering to the following areas:

  • Wing leading edge
  • Wing upper surface
  • Windshield

With ice, snow or slush adhering to the following areas:

  • Wing leading edge and upper wing surface
  • Flight control surfaces
  • Top of fuselage
  • Windshield
  • All static ports
  • Upper surface of engine cowling forward of windshield

Further, according to the PA-46-500TP Meridian POH, “The Meridian ice protection system was designed and tested for operation inPiper_Mirage_01 light to moderate meteorological conditions defined in FAR 25, Appendix C, for continuous maximum and intermittent maximum icing conditions. The ice protection system was not designed or tested for flight in freezing rain, freezing drizzled or supercooled liquid water and ice crystals, or conditions defined as severe. Flight in these conditions is prohibited and must be avoided.” As such, thorough preflight planning becomes vital with respect to known icing conditions; PIREPS are a fantastic source of icing information in your area. Recall that icing is most likely to occur when the OAT is 10 degrees Celsius and below and visual moisture (in the form of clouds, fog, rain, etc) exists.

If you make the decision to fly into known icing conditions within the parameters of the POH, be sure to continuously evaluate the icing situation. If you encounter conditions beyond your capabilities or the legal capabilities of the aircraft, always have a plan to exit the conditions. For the most thorough information, consult your aircraft’s POH or the manufacturer.

Extra notes concerning the PA-46-500TP Meridian:

Minimum speed in icing conditions
   Flaps up – 130 KIAS
Flap settings for icing conditions
   Flaps up while holding
   Max extension – 20°
Minimum torque required for surface deice (Meridian)
    Above 25,000 – 350 ft lb
    Below 25,000 – 250 ft lb
Windshield Heat
      ANTI ICE or DEFOG in Meridian (High or Low setting on Matrix,Malibu and Mirage) while on ground – max 20 seconds
Surface Deice Boots
     Operation is prohibited if temp is below -40°C
Autopilot – prohibited from use if:
      Severe icing conditions exist
      Unusual aileron roll forces
      Elevator bridging
      Frequent autopilot trim annunciator in level flight
Stall Warning Heat
     Location: Leading edge of left wing
            Turn on during flight
            Turn off when greater than 5°C
            System has in-line resistor activated by squat switch for which limits electrical load to 33% of in-flight load
            STALL WARN FAIL indicates lift computer and/or lift transducer failure

Interesting Articles:


Sources: Boeing, AOPA,






About the author

Christopher Carmody has been instructing pilots for over a decade in various aircraft models. He has been awarded the Master Flight Instructor designation by the National Association of Flight Instructors in addition to being recently named "Flight Instructor of the Year" in the FAA's Central Region. He is a former demonstration pilot and regional director of sales of new Piper Aircraft in the midwest. He received his B.S. in Aeronautics majoring in both Aviation Science / Professional Pilot and Aviation Management from Parks College of Engineering, Aviation and Technology at Saint Louis University.