MEP.1.2.1 Speeds

Question 1

VREF?

Answer 1

Term used for the airspeed to achieve on short final. It is the reference airspeed, and we will use Vref +5, Vref +10, or Vref + 15 at varius stages of the approach.

Vref is factored on stalling speed (1,3 Vso) and so varies with weight

Question 2

Vat

Answer 2

Target threshold speed.

It is the last look speed wish to see when you start the flare to land. Vat is based on Vref but can also include allowances for wind, gusts and turbulence

Question 3

Vy

Answer 3

Indicated airspeed for best rate of climb (greatest height in shortest time), with all engines operating

Question 4

Vyse

Answer 4

Airspeed for best rate of climb, single engine and also varies with weight although the manufacturer in the case of light twins, may simply quote the maximum weight case. For the larger acft with a broader range of weights, check for a variation in recommended Vyse with AUW

Blue line is the marking on the airspeed indicator corresponding to Vyse at maximum weight

Question 5

Vx

Answer 5

Airspeed for best angle of climb (greatest height in shortest distance), all engines operating

Question 6

Vxse

Answer 6

Airspeed for best angle of climb, single engine

Question 7

Vso

Answer 7

Stalling speed in the landing configuration with:

• Undercarriage down
• Flap down
• Power off

Question 8

Vs1

Answer 8

Stalling speed with

• Power off
• Undercarriage up
• Flaps up

Question 9

Vle

Answer 9

Maximum speed with the landing gear extended

Question 10

Vlo

Answer 10

Maximum speed with the undercarriage in transit (may be different going up/going down)

Question 11

Vfe

Answer 11

maximum speed with the flaps extended and may vary for different flap settings

Question 12

Vno

Answer 12

Maximum speed for normal operations, in smooth air. Itis known as the maximum structural cruising speed.

Question 13

Vne

Answer 13

Speed that must never be exceeded, under any circumstances

Question 14

Vmca

Answer 14

Minimum control speed, airborne, under specified conditions. This is discussed in some detail later

Question 15

Vmcg

Answer 15

Minimum control speed on the ground and assumes the acft is continuing the take-off. It is not applicable to light twins

Question 16

Vmcl

Answer 16

Minimum control speed in the landing configuration

Question 17

Va

Answer 17

Speed at or below which the airframe cannot be overstressed by control deflection or turbulence. Its significance is that it is proportional to stalling speed and so varies with weight - the heavier the acft, the higher the value of Va

It is also known as the maximum manoeuvring speed.

Question 18

Toss

Answer 18

Take-off safety speed.

It is a nominal speed factored to give a margine above both the stalling speed and minimum control speed. Thus, it is the speed above which the aircraft is safely controllable. However, it does not guarantee any climb performance

Question 19

Vsse

Answer 19

Safe single engine speed is a speed above VMCA, factored to provide a greater safety margin for deliberate asymmetric operations and training.

Question 20

V1

Answer 20

Is the speed at which it is still possible to stop in the remaining distance of the runway and stopway and beyond which the aircraft is committed to continue despite engine failure.

Question 21

V2

Answer 21

take-off safety speed as used by operators of larger aircraft including military. It is factored for Vs and Vmca

Question 22

Vr

Answer 22

Speed at which the aircraft is rotated to the take-off attitude for lift-off

Question 23

Vimd

Answer 23

Indicated airspeed for minimum drag