Division 6Alerting and warning system requirements

Division 6—Alerting and warning system requirements

11.19 Altitude alerting system and assigned altitude indicator

(1) The following aeroplanes must be fitted with altitude alerting equipment in accordance with subsection (2): (a) a piston-engine aeroplane operating in controlled airspace above FL 150; (b) a turbine-engine aeroplane. (2) For subsection (1), the altitude alerting equipment must: (a) include an assigned altitude indicator; and (b) alert the flight crew if the aeroplane approaches a preselected altitude; and (c) alert the flight crew, including by an aural or visual warning, if the aeroplane deviates from a preselected altitude. (3) An aeroplane that is not required to be fitted with altitude alerting equipment under subsection (1) must be fitted with altitude alerting equipment at least in the form of an assigned altitude indicator.

11.20 Aeroplane flown with inoperative altitude alerting equipment or assigned altitude indicator

Despite section 11.19, altitude alerting equipment may be inoperative at the beginning of a flight only if: (a) the flight: (i) begins within 72 hours of the time the equipment was found to be inoperative; and (ii) is from an aerodrome at which there is no facility for the equipment to be repaired or replaced; and (b) for an aeroplane that is required to be fitted with an ACAS—the ACAS is not also inoperative.

Note: For a flight of an aeroplane fitted with inoperative altitude alerting equipment, section 11.07 of the Part 91 Manual of Standards states requirements in relation to air traffic control clearances.

11.20A Radio altimeters

From the beginning of 1 April 2026, each radio altimeter fitted to an aeroplane used for the conduct of a low-visibility approach in Australian territory must comply with the requirements for tolerance to radio frequency interference specified for a “radio altimeter tolerant airplane” in FAA Airworthiness Directive AD 2023-10-02 (FAA AD 2023-10-02) as existing on 26 May 2023.

Note 1: In FAA AD 2023-10-02, a “radio altimeter tolerant airplane” is defined for the purposes of the AD as “one for which the radio altimeter, as installed, demonstrates the tolerances specified in paragraphs (g)(1)(i) and (ii) of this AD, using a method approved by the FAA.”.

Note 2: 26 May 2023 is the date FAA AD 2023-10-02 was published in the Federal Register of the United States Government.