91. Aircraft operating at night or under IFR

An AOC holder must ensure that a large aeroplane that is to be flown at night, in accordance with the Instrument Flight Rules, or when the surface is not in sight, is equipped with a means of measuring and displaying —

magnetic heading;

the time in hours, minutes and seconds;

barometric altitude from 2 independent altimetry sources, at least one of which must be a sensitive pressure altimeter;

airspeed calibrated in knots, with a means of preventing malfunctioning due to either condensation or icing;

mach number, if the speed limitation prescribed by the aeroplane’s flight manual is expressed in terms of mach number;

turn and slip;

aircraft attitude for each required pilot, except in an aeroplane where one of these may be replaced by the turn and slip indicator;

stabilised aircraft heading;

the adequacy of the power supply to any gyroscopic instruments;

outside air temperature; and

rate of climb and descent.

An AOC holder must ensure each attitude indicator provided in accordance with paragraph (1)(g) —

is powered by a separate power source that is capable of automatically continuing to power the indicator for at least 30 minutes after total failure of the main electrical system; and

has an indicator on the instrument panel of the aeroplane to inform the pilot when the attitude indicator is being operated by emergency power. (3) Where the large aeroplane is a pressurised aeroplane, the AOC holder must ensure that the equipment installed to measure barometric altitude in accordance with paragraph (1)(c) has a counter drum pointer or equivalent presentation.

Where a large aeroplane is to be flown at night, the AOC holder must ensure that the aeroplane is equipped with the following lights:

any lights required by the Rules of the Air;

illumination for all flight instruments and equipment essential for the safe operation of the aeroplane;

lights in all passenger compartments;

an independent portable light for each crew member station;

a means to illuminate or detect the formation of ice.

In this regulation, “the surface is not in sight” means that —

the flight crew is not able to see sufficient surface features; or (b)the surface illumination is insufficient to enable the flight crew to maintain the aeroplane in a desired attitude without reference to any flight instrument.

An AOC holder must ensure that a large aeroplane that is to be flown at night, in accordance with the Instrument Flight Rules, or when the surface is not in sight, is equipped with a means of measuring and displaying —

magnetic heading;

the time in hours, minutes and seconds;

barometric altitude from 2 independent altimetry sources, at least one of which must be a sensitive pressure altimeter;

airspeed calibrated in knots, with a means of preventing malfunctioning due to either condensation or icing;

mach number, if the speed limitation prescribed by the aeroplane’s flight manual is expressed in terms of mach number;

turn and slip;

aircraft attitude for each required pilot, except in an aeroplane where one of these may be replaced by the turn and slip indicator;

stabilised aircraft heading;

the adequacy of the power supply to any gyroscopic instruments;

outside air temperature; and

rate of climb and descent.

An AOC holder must ensure each attitude indicator provided in accordance with paragraph (1)(g) —

is powered by a separate power source that is capable of automatically continuing to power the indicator for at least 30 minutes after total failure of the main electrical system; and

has an indicator on the instrument panel of the aeroplane to inform the pilot when the attitude indicator is being operated by emergency power.

Where the large aeroplane is a pressurised aeroplane, the AOC holder must ensure that the equipment installed to measure barometric altitude in accordance with paragraph (1)(c) has a counter drum pointer or equivalent presentation.

Where a large aeroplane is to be flown at night, the AOC holder must ensure that the aeroplane is equipped with the following lights:

any lights required by the Rules of the Air;

illumination for all flight instruments and equipment essential for the safe operation of the aeroplane;

lights in all passenger compartments;

an independent portable light for each crew member station;

a means to illuminate or detect the formation of ice.

In this regulation, “the surface is not in sight” means that —

the flight crew is not able to see sufficient surface features; or (b)the surface illumination is insufficient to enable the flight crew to maintain the aeroplane in a desired attitude without reference to any flight instrument.