On Tue, 13 Jan 2004 at 07:25:32 in message
, C J Campbell
wrote:
I have seen static ports located just about everywhere on fuselages. It
probably does not matter much as long as it is on the side of the fuselage.
If there really was a big pressure difference due to the slipstream on the
fuselage then most static ports would be located toward the aft end, because
the biggest low pressure area would be towards the front, just like a wing.
It appears that the biggest factor in locating the static port is
convenience of plumbing the static lines.

Somebody check my sums but a rough calculation seems to show that the
full dynamic pressure at 300 knots and 35,000ft is about 0.30 lb/sq in

The 8 psi pressure difference is nearly 27 times greater than the full
pitot pressure. The pressure difference between the inside and outside
will be enough to create a shock wave in the hole and very high speed
flow. I cannot do the sum to estimate the velocity at present. Hence the
'explosive' decompression if the hole is of such a size that air can
escape initially at sonic or supersonic speed.

The possible pitot pressure is thus negligible at 35,000ft compared to
the cabin pressure.
--
David CL Francis