AMC 22.1549(d) Power-plant instruments

CAA ORS9 Decision No. 1

In the case of digital solid state displays the required red line should be represented by a steady red light near or on the instrument, or by blinking of the whole display. The precautionary range should be indicated near or on the instrument. All instrument indications in that range should be designed to obtain the attention of the pilot. In addition, the operating range data should be placarded near the display using the colours described in CS 22.1549(a), (b) and (c).

Oil temperature, oil pressure and cylinder head temperature indications will be acceptable if achieved by means of warning lights instead of analogue or digital indications if:

(1) The required red line is represented by a steady red light.

(2) The normal operating range is represented by a steady green light.

(3) The precautionary range is represented by a steady yellow light.

(4) A ‘press to test’ facility is provided for the warning light displays.