CS 25J1549 APU instruments

For each APU instrument either a placard or colour markings or an acceptable combination must be provided to convey information on the maximum and (where applicable) minimum operating limits. Colour coding must comply with the following:

(a)Each maximum and, if applicable, minimum safe operating limit must be marked with a red radial or a red line;

(b)Each normal operating range must be marked with a green arc or green line, not extending beyond the maximum and minimum safe limits;

(c)Each precautionary operating range must be marked with a yellow arc or a yellow line; and

(d)Each APU speed range that is restricted because of excessive vibration stresses must be marked with red arcs or red lines.

[Amdt 25/1]