n5296s
17th Feb 2006, 09:08
(I guess this is as good a forum as any for this question)
Most of the inflight map systems show altitude as an exact thousand, to a degree of precision which I'm sure does not reflect reality. However today I flew LHR-NRT with Virgin and the altitude was all over the place, not just a few feet off but often showing several hundred different from a proper flight level - way off what I would personally consider acceptable when I'm the one flying the plane. (Even my relatively cheap GA autopilot can keep altitude to within 20' or so in smooth air).
So I was wondering where they get this data from? I find it hard to believe either:
a) AA, UA, BA etc can really fly to an accuracy of 0.5'
b) VS can't fly to an accuracy of 500'
Any illumination welcome...
n5296s
Most of the inflight map systems show altitude as an exact thousand, to a degree of precision which I'm sure does not reflect reality. However today I flew LHR-NRT with Virgin and the altitude was all over the place, not just a few feet off but often showing several hundred different from a proper flight level - way off what I would personally consider acceptable when I'm the one flying the plane. (Even my relatively cheap GA autopilot can keep altitude to within 20' or so in smooth air).
So I was wondering where they get this data from? I find it hard to believe either:
a) AA, UA, BA etc can really fly to an accuracy of 0.5'
b) VS can't fly to an accuracy of 500'
Any illumination welcome...
n5296s