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1st Sep 2010, 19:11

#545 (permalink)

PEI_3721

Join Date: Mar 2006

Location: England

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WhatsaLizad-II, I believe this to be the 15% (1.15 factor) from my post # 521, and thus relates to FAA in-flight planning. European wet data is based on a 1.92 factor (EU OPS-1.520).

BOAC, your reference in meters (305m vs 1000ft touchdown distance), appears to differ from mine – a European version?
Interesting if so, as few EU operators would require a 15% calculation, instead requiring EU-OPS fully factored data.

A correction to my reference – it is dated Dec 2005.

I urge caution in the use of Braking Action, particularly if given by PIREP.
Reported braking action based on an inspection of runway would be better, but what is the accuracy of the measurement, and what is the runway surface composition, or maintenance condition.
I will gladly expand on the issues, but first see EASA - Workshop Runway Friction and Aircraft Braking
Presentations, 2.2 FAA TALPA, slides 16 – 20.
Balance the US operator views in other presentations with the more muted views of PIREPS from the manufacturers.
How do pilots know what is normal or reduced braking; reduced from what?

Note that this accident involved a non grooved runway; see the issues discussed in http://www.pprune.org/rumours-news/4...rrun-cyqm.html

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