Airspeed Indicator Markings

The airspeed indicator turns the airspeed limits into colour you can read at a glance in flight. This lesson covers the P2006T's ASI markings — the white, green and yellow bands and the blue and red radial lines — and what each boundary means.

At a glance

• White band54–93 KIAS
• Green band66–138 KIAS
• Yellow band138–171 KIAS
• Blue line84 KIAS
• Red line (lower)62 KIAS
• Red line (upper)171 KIAS

The colour bands

• White band, 54–93 KIAS — its lower limit is V_S0 and its upper limit is the maximum allowable speed with flaps extended in the LND position.

• Green band, 66–138 KIAS — the normal operating range: the lower limit is the stall speed with flaps up, V_S1, and the upper limit is the maximum structural cruising speed, V_NO.

• Yellow band, 138–171 KIAS — manoeuvres must be conducted with caution and only in smooth air.

The radial lines

• Blue line, 84 KIAS — best rate-of-climb speed with one engine inoperative.

• Red line, 62 KIAS — minimum control speed with one engine inoperative and flaps set to T.O.

• Red line, 171 KIAS — maximum speed for all operations.

Figure: Airspeed indicator markings (redrawn).

Check yourself

• What do the lower and upper limits of the white band represent?

• What speeds bound the green band, and what does each end mark?

• What does the blue line indicate, and at what speed is it set?

• There are two red lines — what does each one mean?

Study aid — always fly your aircraft's current AFM/POH.