NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Long-range airplane navigation
From: Gennaro Sammarco
Date: 2004 Nov 29, 09:39 +0100
From: Gennaro Sammarco
Date: 2004 Nov 29, 09:39 +0100
I think you are right, Ken, and probably I expressed myself in a non correct way. As matter of fact, the trnd today is to base navigation on the always more reliable systems and the redundancy of them aboard. Besides the traffic is so strongly increasing that minimum separations are required, then the necessity of accurate position fixing even in the middle of Atlantic. Gennaro Sammarco > Hi Guys, > > I feel like I should not let this moment pass without saying something > about aircraft navigation, since that has been my background. It was > suggested that high speeds have contributed to the demise of CN in > airplanes. I believe it has been the proliferation of electronic methods > rather than high speeds that caused this. High speeds are themselves no > problem, except for neophyte navigators (and for that matter pilots too). > It merely requires ?staying ahead of the airplane?. > When I was with Boeing, we routinely ferried ?green? 707s across the north > Atlantic. Green meant that the planes had only the bare rudiments of nav > equipment, effective within 150 miles from land. Oceanic navigation was > purely celestial (usually one sextant, one man, and a box lunch). Apre? > flight analysis usually revealed that the plane could be kept to within 4 nm > of intended track by taking a series of sextant sights every 40 minutes. > An interesting aspect for this group might be that coriolis and rhumb line > corrections were extremely important aspects of bubble sextant operation, > and could reach as high as 28 nm at 450 kts at high latitudes. > > Ken Gebhart