Airspeed Limitations

This is the only chapter of the manual that carries EASA approval, and its opening pages set the speeds you may not cross. Learn the numbers with the conditions attached — several of them change with mass or flap setting, and one of them changes if a design change advisory has been embodied.

At a glance

• V_NE (never exceed, smooth air)188 KIAS
• V_NO (max structural cruising)151 KIAS
• V_O (above 1800 kg)122 KIAS
• V_O (1700-1800 kg)119 KIAS
• V_O (up to 1700 kg)112 KIAS
• V_FE (flaps LDG)113 KIAS
• V_FE (flaps APP)133 KIAS
• V_LOE (gear extension)188 KIAS
• V_LOR (gear retraction)152 KIAS
• V_LE (gear extended)188 KIAS
• V_MCA (flaps UP)76 KIAS
• V_MCA (flaps APP)73 KIAS

What approval means here

The limitations in this chapter are approved, and operation of the airplane outside them is not permissible. There is a maintenance consequence too: exceeding an operating limitation that relates to a physical property of the airplane — speeds, load factors, weights — requires unscheduled maintenance before the aeroplane flies again.

Manoeuvring speed changes with mass

V_O is not a single number. Above 1800 kg (3968 lb) it is 122 KIAS; above 1700 kg (3748 lb) and up to 1800 kg it is 119 KIAS; up to 1700 kg it is 112 KIAS. Above whichever figure applies, full or abrupt control surface movement is not permissible.

The direction of that relationship is the part worth fixing: the lighter the aeroplane, the lower the speed at which you must stop making full control inputs.

Flap and landing gear speeds

Select LDG and the ceiling becomes 113 KIAS; select APP and it becomes 133 KIAS. Whichever setting is out, its figure binds you.

The gear gives you three separate figures. Extension may not be carried out above 188 KIAS and retraction not above 152 KIAS, while flight with the gear already extended is limited to 188 KIAS. Extension and flying gear-down share a number; retraction is the odd one out, 36 knots lower.

Minimum control speed

With one engine inoperative the airspeed must stay above V_MCA: 76 KIAS with flaps UP, and 73 KIAS with flaps at APP.

Structural cruising and never exceed

V_NO is 151 KIAS. Smooth air is the only condition in which you may go past it, and even there you go carefully. V_NE is 188 KIAS, and nothing you do in this aeroplane may take you beyond it.

How the airspeed indicator says all of this

The markings on the airspeed indicator restate these limits as colour.

Arcs and radials

• White arc — 62 to 113 KIAS, the operating range with flaps fully extended. If MÄM 42-678 has been carried out the arc begins at 64 KIAS instead.

• Green arc — 69 to 151 KIAS, the normal operating range. With MÄM 42-678 carried out it begins at 72 KIAS.

• Yellow arc — 151 to 188 KIAS: a caution band you enter only when the air is smooth.

• Blue radial — 85 KIAS, best rate of climb speed on one engine.

• Red radials — 76 KIAS, the single-engine minimum control speed, and 188 KIAS, the maximum speed for all operations.

Figure: Airspeed indicator markings (redrawn).

Two of the arcs move if MÄM 42-678 has been embodied, and both move at their lower end only. The top of the white arc and the top of the green arc are unaffected.

Check yourself

• What are the three V_O figures, and which mass band does each belong to?

• Which two gear speeds share the same value, and which one differs?

• What are the two V_MCA figures, and what distinguishes them?

• Which two arcs change if MÄM 42-678 is carried out, and at which end?

• What does exceeding a speed limitation oblige you to do before the next flight?

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