My understanding of precision was both lateral and vertical guidance. If a GPS approach with WAAS provides both, why is it still considered non-precision?
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I believe I've seen the explanation somewhere around the site already, but it is not present in the similar question the search manages to find, http://aviation.stackexchange.com/questions/6341/is-lpv-considered-a-precision-approach (it only says it is non-precision, but not why). – Jan Hudec Apr 04 '16 at 11:35
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5@JanHudec This one? – Pondlife Apr 04 '16 at 13:02
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@Pondlife, yes, that one looks like a good duplicate. – Jan Hudec Apr 04 '16 at 13:22
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@JanHudec I think it's a dupe, but unfortunately the only answer on the other question doesn't make any sense (to me), unless I missed something. That doesn't change the dupe thing, of course. – Pondlife Apr 04 '16 at 13:48
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@Pondlife the answer that is linked states that a non-precision approach with vertical guidance is considered that because onboard instruments compute the planes location. However with WAAS, there are ground based stations outside of the aircraft which help compute this. – jskypilot Apr 05 '16 at 10:56
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@jskypilot Even with WAAS, the onboard GPS unit determines the aircraft's position, not the ground stations. And Wikipedia's list of SBAS solutions shows that they all (?) use ground stations. – Pondlife Apr 05 '16 at 14:51
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@Pondlife Not sure if duplicate. The other question asks about why LPV SBAS is not a precision approach by ICAO. This one asks why LPV using the US SBAS is not a precision approach. – jinawee Jun 05 '19 at 14:30