20 Additional Take Off Techniques

Question 1

What is the purpose of the Increased V2 Take Off Procedure and what does it give?

Answer 1

• By increasing V2, the AC speed on the initial climb will be closer to Vmd
• Therefore, less drag, more excess thrust and better climb performance
• Used on long runways to increase CLTOM

Question 2

What are the dangers of using the Increased V2 Take Off procedure?

Answer 2

• Risk of hot brakes/fire, burst tyres from exceeding Vmbe on an aborted T/O
• Higher V1 speed

Question 3

Under what conditions is it not permitted to use a Reduced Thrust Take Off procedure?

Answer 3

• Icing/slippery runway surface
• Contaminated runway
• Using an increased V2 procedure
• Anti-skid is inoperable
• Reverse thrust is inoperable
• PMC inoperable
• Adverse weather

Question 4

Is TOGA available whilst using the following procedures:

• Reduced Thrust
• Derated

Answer 4

• Reduced Thrust: TOGA is still available

- Derated: TOGA is no longer available

Question 5

What advantages are gained through using a Derated Take Off procedure?

Answer 5

• Saves engine life
• Reduced Vmcg and Vmca speeds
• Therefore can have reduced V1, VR and V2 speeds

Question 6

Under what conditions is a runway considered contaminated?

Answer 6

• 25% covered

- 3mm depth

Question 7

What is the formula for the equivalent depth of contamination on a runway?

Answer 7

Depth x SG

Question 8

What is Vp?

Answer 8

Vp is velocity at which the AC starts aquaplaning (hydroplaning)

Question 9

What is the equation for Vp?

Answer 9

Vp = 9 x sqrt(Psi)

Question 10

Under what conditions do the CAA prohibit landing of a Class A AC on a contaminated runway?

Answer 10

• Tailwind
• > 15mm of water, slush or wet snow
• > 80mm of dry snow

Question 11

Describe the three types of Aquaplaning (Hydroplaning)

Answer 11

Dynamic:

• AC wheels are going too fast to move the water out the way
• Water goes under the wheels and the AC glides on top

Reverted Rubber:

• Does not require any depth of contamination, just damp
• Braking causes the water to heat
• Compression from wheel weight also heats water
• Water turns to steam
• AC glides on pocket of steam
• Can melt the tyres

Viscous:

• Rubber from tyres is left on runway surface
• When rubber becomes wet it becomes very slippery

Question 12

When performing a reduced thrust take off procedure, what is the maximum assumed temperature allowed for the calculation?

Answer 12

+ 55 degrees