Aviation could use hPa for atmospheric pressure its own reasons; however, it is no reason that the public and everyone else should do it. The public and others should be given atmospheric pressure in kPa to be compatible with common practice and safety.
Atmospheric pressure is observed and used in weather forecasting in tenths of mbar/tenths of hPa. Whole hPa truncates those tenths. So why not report atmospheric pressure in kPa to two decimal places and retain the precision since a decimal point is included anyway? In the US, pressure is reported to two decimal places in inches of Hg on radio and TV now. The conversion to inches of Hg from metric observations introduces inaccuracies. So why introduce inaccuracies when it is not necessary? Stan Doore ----- Original Message ----- From: "Carl Sorenson" <[EMAIL PROTECTED]> To: "U.S. Metric Association" <[EMAIL PROTECTED]> Sent: Monday, March 24, 2003 1:31 AM Subject: [USMA:25293] hPa > >From Michael Payne: > >If the pressure for aviation were changed to > >kPa we would have to use the decimal point. > >I prefer that we use a whole number, the difference > >between each 1 hPa of pressure is roughly 10 m on an > >altimeter, which is inconsequential. > > >Lets face it, the hPa is a very convenient unit > >for Aviation! > > Agreed! Let's not sacrifice convenience for an artificial rigidity in which > units we use. > > Carl >
