E414 - Epic E1000 N98FK Crash at Steamboat Springs: LNAV+V Advisory Glidepath Trap

An Epic E1000, N98FK, crashed near Steamboat Springs, Colorado during a night RNAV (GPS) approach. The lateral track was almost perfect, but the vertical profile was fatal: the airplane remained on an LNAV+V "advisory glide slope" and descended below the 9,100-foot MDA into terrain.

Max explains what Garmin calls Advisory Vertical Guidance, why LNAV+V can look nearly identical to an LPV on the PFD, and why it does not provide obstacle protection below minimums. He shows the airplane crossed the FAF MABKY and stepdown fix WDCHK essentially on...