Advanced Take-Off Techniques

Question 1

Flex take-off not permitted under what conditions?

(6 items)

Answer 1

icy/slippery runways

contaminated runways

anti-skid inop

t/rev inop

increased V2 procedure

PMC off

Question 2

th equivalent water depth of a contaminant on a runway can be found by …

Answer 2

multiplying the contaminant depth by the SG of the contaminant

Question 3

all runway contaminants act to resist … on the t/o run, except …

Answer 3

acceleration

ice

Question 4

Dynamic hydroplaning

The point at which the aircraft starts to plane is called the hydroplaning speed (Vp) and it can be approximated by the formula

Vp =

If the wheel is not rotating the formula becomes:

Answer 4

9 x square root of (P/p) for a rotating wheel

7.7 x square root of (P/p)

P is wheel pressure

p is contaminant SG

Question 5

what is viscous hydroplaning?

Answer 5

A thin film of fluid on a smooth dirty runway prevents the tyre contacting the surface

Can occur at a much lower speed than dynamic hydroplaning

Question 6

what is reverted rubber hydroplaning?

Answer 6

Occurs after a skid, often on the nosewheel which has neither braking nor anti-skid protection

The high temps created by friction boil a thin layer of water and vaporised rubber to steam to support the tyre

Likely if NWS is used indiscriminately on a slippery runway

Can occur at slow speeds

Question 7

Runways that are wet or contaminated assume … braking action with a co-efficient of … or less

Answer 7

poor

0.25

Question 8

What is good braking coefficient and its SNOTAM code?

Answer 8

>0.4

code 5

Question 9

What is medium to good braking coefficient and its SNOTAM code?

Answer 9

0.36 - 0.36

code 4

Question 10

What is medium braking coefficient and its SNOTAM code?

Answer 10

0.35 - 0.30

code 3

Question 11

What is medium to poor braking coefficient and its SNOTAM code?

Answer 11

0.29 - 0.26

code 2

Question 12

What is poor braking coefficient and its SNOTAM code?

Answer 12

<0.25

code 1