Take Off - Initial Climb

What is Vfto?

Final take off speed

- Minimum clean speed

- Speed between final flap retraction and fourth segment

- Must be able to maintain 40° banked turn

What is V3?

Initial climb speed at screen height AEO

What is V4?

Speed flap retraction should be initiaed at AEO

When is the takeoff path go to?

From BRP to 1500ft, it's divided into four segments

*1500ft reached after enroute transition complete and Vfto reached

What is the minimum OEI climb gradient for the first segment?

>0.0%

What is the minimum OEI climb gradient for the second segment?

2.4%

What is the minimum OEI climb gradient for the third segment?

nil required

*but climb gradient available must be 1.2%

What is the minimum OEI climb gradient for the fourth segment?

1.2%

What indicates the starts and end of the first segment?

Start: Screen height

End: Gear fully retracted

What indicates the starts and end of the second segment?

Start: Gear fully retracted

End: Acceleration height reached

What indicates the starts and end of the third segment?

Start: Acceleration height reached (retract flaps)

End: Enroute configuration

What indicates the starts and end of the fourth segment?

Start: Enroute configuration

End: 1500ft

What are the slats/flaps configuration during each segment?

First: Takeoff

Second: Takeoff

Third: Retraction

Fourth: Clean

What is the configuration of the landing gear during each segment?

First: Retraction

Second: Retracted

Third: Retracted

Fourth: Retracted

What is the planned thrust setting for each segment (for the gross path)?

First: TOGAn-1

Second: TOGAn-1

Third: TOGAn-1

Fourth: MCT

What is the speed during each segment?

First: V2

Second: V2

Third: Accelerate

Fourth: Vfto

Why is a gradient penalty applied to the first, second and fourth segments gross flight path?

To clear obstacles by a set margin (safety factor)

0.8% for a twin aircraft

What are the obstacle clearance margins for a straight departure (within 15° AoB)?

Dry: 35ft

Wet/contaminated: 15ft

What are the obstacle clearance margins for a turning departure (more than 15° AoB)?

Dry: 50ft

Wet/contaminated: 30ft

How do you work out the half width of the takeoff obstacle fan?

75m + 0.125D

*12.5% increase after 75m

What is the maximum half width of a departure?

Straight (track change ≤ 15°): 300m

Turning (track change > 15°): 600m

When will and operator design an EFATO procedure?

If OEI climb performance doesn't meet obstacle clearance requirements

Do you need to increase thrust if takeoff is planned with reduced thrust and there is an EFATO?

No since performance calculations are based on engine failure at Vef but can if needed

How does wind affect a climb gradient?

Headwind: Increases

Tailwind: Decreases

How does increased temperature affect climb gradient?

Decreases

How does increased pressure altitude affect climb gradient?

Decreases

How will increasing V1/Vr affect MTOW and obstacle clearance?

Won't change MTOW

Reduces TODR so takeoff path starts earlier and less performance needed to clear obstacles

If a takeoff is limited by the second segment climb gradient, what does increasing V2 do?

Optimises climb gradient (better climb using extra runway to accelerate), more likely to increase clearance from further away obstacles

What can a takeoff be limited by?

Structural

- MTOW

Performance

- Field length (TODR, TORR, ASDR, brake energy, tire speed)

- Obstacles

- Climb gradient