FAA Instrument Flight Instructor (FII)Instruments and SystemsEasy
On a standard airspeed indicator, the upper limit of the green arc (transitioning into the yellow arc) represents which airspeed?
- AVNE, never-exceed speed
- BVNO, maximum structural cruising speed
- CVS1, stalling speed in clean configuration
- DVFE, maximum flap-extended speed
Show answer & explanationAnswer & explanation
Correct answer: B. VNO, maximum structural cruising speed
The top of the green arc marks VNO, the maximum structural cruising speed — operation above this speed (into the yellow caution arc) is permitted only in smooth air. VNE is marked by the red line at the top of the yellow arc, and VFE is the top of the white arc.
Why the other options are wrong
- A. VNE is the red radial line at the top of the yellow arc, not the green/yellow boundary.
- C. VS1 is the bottom of the green arc, not the top.
- D. VFE marks the top of the white (flap) arc, unrelated to the green/yellow boundary.
Airspeed Indicator Color Arcs
Color-coded arcs on the airspeed indicator denote operating speed ranges: white (flap range), green (normal), yellow (caution), and a red line (never-exceed).
- Green arc top = VNO (max structural cruising speed)
- Yellow arc = caution range, smooth air only
- Red line = VNE, never-exceed speed
Memory trick: Green tops out at 'NO-go-fast' (VNO) before yellow caution.