On Jul 17, 10:18*am, geoff wrote:
In message
,
harry writes





On Jul 16, 11:03*pm, Charles Ellson
wrote:
On Sat, 16 Jul 2011 22:40:07 +0100, The Natural Philosopher

wrote:
Graeme Wall wrote:
On 16/07/2011 10:24, Guy Gorton wrote:
That seems very low. *My facts may be wrong but I think 30ft of water
creates 1 atmosphere of pressure, which is about 14 lbs/sq.in.

If I remember my schoolboy physics, it's 32ft of water and 15lbs/sq..in.

32.2 & 14.4 rings a bell..

14.7 rings it better unless you're somewhere up a mountain.

NPT = 1013 millibars at sea level. * We've gone metric, haven't you
heard?

It was supposed to be 1000mb but Napoleon's scientists got it wrong.

Not french by any chance, are you harry?

--
geoff- Hide quoted text -

- Show quoted text -

I used to fly. 1013 is the pressure you set your altimeter at away
from airfields so it is ingrained into the brain.
This is so everyone is flying at altitudes from the same basis.