31 July 2011 C1 CIVIL AVIATION DEPARTMENT HONG KONG ...

2 Requirement2.1 Compliance with paragraphs 2.2 and 2.3 of this Notice, or with a CADapproved alternative providing an equivalent level of safety, is required assoon as practical but not later than 1 January 1974, for:(a)aircraft certificated in the Transport Category for the carriage of morethan 19 persons over the age of three years; and(b) aircraft the maximum total weight authorized of which exceeds 15,000kg.2.1.1 Where it can be shown that an aircraft detailed in 2.1(a) or (b) will bepermanently removed from service prior to the 1 January 1975, theDirector-General may, on application, waive the requirements of thisNotice where he is satisfied that compliance would not be justified inthe circumstances of the particular case.2.1.2 Compliance will also be required for newly constructed aircraft themaximum total weight authorized of which exceeds 5700 kg, for whicha Hong Kong Certificate of Airworthiness in the Transport Category isfirst issued on or after 1 January 1974.2.2 Where it cannot be shown that in the event of a total failure of the mainelectrical generating system, an adequate supply will be availableautomatically to a suitable bank and pitch indicator for a minimum period of30 minutes, assuming that no special crew action is taken for 10 minutes, thena separate emergency supply, independent of the aircraft electrical generatingsystem, which will automatically supply such an instrument, and its associatedlighting, for a minimum period of 30 minutes, shall be provided.2.2.1 Where the emergency supply is provided by a separate battery it ispermissible for this battery to be (trickle) charged from the mainelectrical generating system, provided that the installation is such thatthe battery cannot discharge back into the main system.2.3 The instrument supplied in accordance with 2.2 shall be:(a)(b)the third instrument (standby horizon) where this is provided, or failingsuch provision,the bank and pitch indicator fitted to the Captain's flight instrumentpanel.2.3.1 Where the third instrument is fitted it shall:30 May 2006 AN-81 P.2