Comparing LPV and ILS
They look pretty similar, so is LPV just another name for an ILS that uses GPS? It turns out that if you’ve seen one glidepath, you haven’t seen them all.
A rriving at your destination on a dreary day, ATC queries you with “say approach requested.” The landing runway has an ILS and an RNAV (GPS) approach with identical LPV minimums published. Which do you choose? You would be forgiven for thinking, as we initially did, that this is a bit of an inconsequential question. WAAS has enabled satellite guided approaches to have precision comparable to Category I ILS approaches, so what difference does it make? Although true, this doesn’t mean that ILS and LPV are identical in all regards.