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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Ah, give someone a calculator.......
From: Gary LaPook
Date: 2010 Aug 14, 23:11 +0200
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: http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=fcb7f258c93bc5abf78002493329d3a3&rgn=div8&view=text&node=14:2.0.1.3.10.2.6.45&idno=14 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. gl 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 > > > > >