Aviation News Talk Podcast

Max talks about common gotchas with RNAV GPS approaches, especially when using vectors to final (VTF). The conversation picks up where Episode 383 left off, with listeners asking how vectors to final (VTF) influences glidepath capture on WAAS approaches. He explains that under normal circumstances—flying the approach via own navigation from an initial approach fix (IAF)—the GPS glidepath doesn’t turn magenta or allow autopilot coupling until the FAF becomes the active waypoint. The magenta color indicates that the GPS receiver has completed a signal quality evaluation, verifying that the WAAS signal is good enough for LPV minimums. Until this point, the glidepath indicator remains a hollow white diamond, and the autopilot will not descend. However, activating VTF triggers this signal check immediately, regardless of the aircraft’s location. If the aircraft’s track is within approximately 100–110° of the final approach course, the glidepath indicator turns magenta and autopilot coupling becomes possible