Summary EASA ATPL - Performance

THE

PILOT




performance
ATPL
STUDENT
pilot
resume
all info you need to pass atpl exams

, V-SPEEDS

VX:
- Best/max angle of climb speed, climb at slower speed but steeper angle
- Max obstacle clearance
- Speed for which the ratio of climb & forward speed is maximum
- Max excess thrust (thrust available - thrust required = max = best angle)
- Max obstacle clearance with no high lift devices, may be lower or equal to V Y
VY:
- Best rate of climb speed, climb at shallower angle but reach altitude faster
- Speed for best rate of climb, maximum height in shortest time
- Maximum excess power (power available - power required = max = best R/C)




*** Remember power required curve vs drag/thrust curve. Tangent for power req = V MD & for drag/thrust req = 1.32
V MD

Jets:
- V MD = min thrust required/min drag speed (Min thrust = min drag)
- Best angle of climb V X = V MD = Best endurance = speed for max L/D = Holding speed
- Best rate of climb V Y = 1.32V MD = speed for best range = Best EAS/Drag ratio = Best NAM/kg

Propeller:
- Best angle of climb V X = V MP = Best endurance
- Best rate of climb V Y = V MD = Best range = speed for max L/D

Glide:
- V MP : For maximum glide endurance (Both jets & prop) min ROD
- V MD : Minimum drag for maximum range (Glide further) proportional to aircraft mass

Drift down:
- Best speed to descend after OEI (Jets): V MD = V X (Least rate of descent) (Best OEI angle of climb speed)
- Best speed to descend after OEI (Props): V MD = V Y (Best OEI rate of climb speed turboprops)
- V X – V XSE – V YSE – V Y

V S : Stall speed/min steady flight speed airplane is controllable
V SR : Reference stalls speed (6% higher than V S )
V SO : Stall speed/min steady flight speed airplane is controllable in landing configuration
V REF :
- Landing reference speed = V SO x 1.3
- Constant in turbulent conditions
- Landing speed: 1.23 V SRO = V REF (Up to 50ft)
V P : Aquaplaning speed
V LO : Maximum speed for landing gear operation