On 23 September 2012 a Ryanair Boeing 737-800 made a premature descent to 450 feet agl in day VMC whilst turning right onto visual finals for runway 24 at Memmingen after the FMS selected altitude had been set to a figure only 44 feet above runway threshold elevation of 2052 feet amsl. EGPWS Alerts of Sink Rate’ and Caution Terrain’ prompted initiation of a go around which, as it was initiated, was accompanied by a an EGPWS TERRAIN PULL UP’ warning. The go around and a second successful approach to runway 24 were uneventful. The Investigation is not yet complete.