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    Re: Ah, give someone a calculator.......
    From: Gary LaPook
    Date: 2010 Aug 14, 23:11 +0200

    I'm guessing that the "decent"units you are hinting at are meters. But 
    then you run into problems with flight levels. To avoid midair 
    collisions aircraft fly at different flight levels depending on the 
    direction of flight.  Aircraft proceeding generally eastbound, on 
    magnetic courses of 0� to 189�,  fly at odd thousands of feet and 
    aircraft generally westbound, 180� to 359�, at even thousands of feet. 
    (Talking about instrument flight rules here, visual flight rules are 
    similar.) See Federal Flight Regulation 91.179 at:
    International, ICAO, rules are the same.
    The thousand foot spacing prevents head on mid air collisions by 
    compensating for inaccuracy in the altimeters and for less than perfect 
    pilot technique in maintaining assigned altitudes.
    But if we switched to meters then we would have to space flight levels 
    1000 meters apart which is too great since such large spacing is not 
    necessary for safety and would eliminate 2/3 of all the current flight 
    levels which would cause more planes to be operating on the few 
    remaining flight levels making them more crowded and collisions more 
    likely. And 100 meter spacing would not be great enough spacing given 
    the above factors.
    So, I think we will just stick to using feet in aviation.
    Marcel Tschudin wrote:
    > That's the punishment for using originally some "strange" units. The
    > problem wouldn't exist if all would use the same "decent" units ;-)
    > BTW: I find this Web-page useful for obtaining statistical data from a
    > location. The forecasts however don't seem to be very reliable.
    > Marcel

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