Document ID: chunk:federal_register_of_legislation:F2006B07622:body:0:p1
Version: federal_register_of_legislation:F2006B07622
Segment Type: other
Provision Reference: 
Character Range: 20–3123

AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

 Harbin Y12 Series Aeroplanes

AD/Y12/8 Aircraft Flight Manual, Flight into Icing Conditions 3/2003

 Applicability: All Y12II aeroplanes.

              Requirement: 1. Revise the CAAC and FAA approved Airplane Flight Manual (AFM) by incorporating the following into the Limitations Section of the AFM:

              "Except for certain phases of flight where the AFM specifies that de-icing boots should not be used (e.g. take-off, final approach, and landing), compliance with the following is required.

                  1. Wing and Tail Leading Edge Pneumatic De-icing Boot System, if installed, must be activated:

                    1. At the first sign of ice formation anywhere on the aircraft, or upon annunciation from an ice detector system, whichever occurs first; and

                    ii.        The system must either be continued to be operated in the automatic cycling mode, if available; or the system must be manually cycled as needed to minimize the ice accretion on the airframe.

b.        The wing and tail leading edge pneumatic de-icing boot system may be deactivated only after leaving icing conditions and after the airplane is determined to be clear of ice."

              2.        Revise the CAAC and FAA approved Airplane Flight Manual (AFM) by incorporating the following into the Limitations Section of the AFM:

                    "WARNING

              Severe icing may result from environmental conditions outside of those for which the airplane is certificated. Flight in freezing drizzle, or mixed icing conditions (supercooled liquid water and ice crystals) may result in ice build-up on protected surfaces exceeding the capability of the ice protection system, or may result in ice forming aft of the protected surfaces. This ice may not be shed using the ice protection systems, and may seriously degrade the performance and controllability of the airplane.

Harbin Y12 Series Aeroplanes

 AD/Y12/8 (Continued)

              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 (ATC) to facilitate a route or an altitude change to exit the icing conditions:

                  1. Unusually extensive ice accumulation on the airframe and windshield in areas not normally observed