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Old 20th May 2015, 04:59
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john_tullamarine
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Interesting.

In the first instance, an operator can schedule however it wishes so long as the protocol accords with AFM limitations/requirements and any local regulatory matters.

Consider -

1- Use normal take off.

Not a concern for the operation

2-Improve climb.

If you have the runway to spare and no restriction such as a close in noise abatement concern, this is the generally preferred option as it loads the dice towards the crew in the event of a problem during the takeoff. Caveat - not much sense using overspeed if that converts a non-limiting ASDR into a limiting situation.

3-And last resource engine bleed off take off.

Bleed off generally is only a desirable option if the takeoff is limited bleeds on and you can get the last few kilos required with bleeds off. There is little point in going bleeds off for the sake of it as it just interposes an additional risk for a post takeoff reconfiguration screw up ...

documentation ?

Probably not as this is an operator choice matter.


Me, I'd prefer

(a) overspeed (improved climb) if there is plenty of runway and no other considerations of note

(b) normal

(c) bleeds off only if that is the only way to make the RTOW.
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