The pressure of 88.2 kPa is the lowest pressure recorded at sea level.  In
1975 a Lufthansa Jumbo Jet crashed into the ground at Nairobi (altitude
about 1700m) while landing killing about half the passengers when the pilot
dialled 938 mbar as the ground pressure rather than 839 mbar.

>From an aviation point of view, millibars are preferable to kPa as the
pressure drop is about 1 mBar per 10 m as opposed to 1 kPa per 100m.  This
means that pilots can tune their barometers to within 10m without having to
use a decimal point or superfluous zeros.  Although I am not a pilot, I
believe that the last 20 m or 30 m of the pilot's descent is visual, so an
accuracy of 10 m is sufficient. Of course the same argument holds for hPa.

Finally, before I am corrected by anybody, I am aware that aviators in the
Western world measure altitude in feet rather than metres.

----- Original Message ----- 
From: "Pierre Abbat" <[EMAIL PROTECTED]>
To: "U.S. Metric Association" <[email protected]>
Sent: Wednesday, December 28, 2005 8:21 PM
Subject: [USMA:35492] Re: Weather channel web site and millibars


>
> Those should be daPa and Pa and dPa respectively.
>
> The lowest pressure recorded was 88.2 kPa (or something like
> that; it's on the whiteboard at work),  [... snip ...]
>
> phma
>

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