10 m is not inconsequential when flying an ILS to minimums. Standard Decision Height(DH) is 200 ft fot a CAT I approach. 100 ft for a CAT II and lower for CAT III. Radar altimeters are of course required for CAT III approaches plus many other requirements. For CAT I and CAT II a 10 m error does not fall into the realm of inconsequential.
Baron Carter CFI,CFII,MEI -----Original Message----- From: Michael Payne [mailto:[EMAIL PROTECTED] Sent: Sunday, 23 March, 2003 15:54 To: U.S. Metric Association Subject: [USMA:25283] RE: Mass Aircraft Altimeters are calibrated for both inHg and hPa (or mBars) only, Canada and the USA at present gives pilots only inches of Mercury, Russia give the pressure in mm of mercury with hPa as an option. Just about everyone else gives out hPa. 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! Michael Payne > [Original Message] > From: Pat Naughtin <[EMAIL PROTECTED]> Can > anyone tell us if use of the kilopascal in weather reports causes any > problems. I believe that it is best in the long run to have only one unit > for each quantity used in all nations =AD my preference is kilopascal. Do air > pilots have an air pressure issue when they fly from a hectopascal region t= > o > --- Michael Payne --- [EMAIL PROTECTED] --- EarthLink: The #1 provider of the Real Internet.
