The LPV-Converter resolves the arising problem with the LPV/VNAV-approach that appears, when an aircraft is equipped with an EFIS system (e.g. Honeywell SPZ5000 in Cessna 525 or Thales system in EC135/145) and a SBAS capable (WAAS/EGNOS) FMS/GPS with an ARINC429 interface.

In ILS mode, the EFIS system expects ARINC429 localizer deviation, glideslope deviation and ILS energize information. If a LPV/VNAV approach is active, the LPV/VNAV-Converter switches the ARINC GPS output from the Garmin unit into the NAV input of the EFIS system. The LPV/VNAV Converter extracts ARINC429 data and the DME compliant data from any SBAS capable FMS/GPS datastream and fits additional labels into the generated modified datastream to the EFIS system.

Due to the missing glideslope feature of the EFIS, the LPV/VNAV –Converter simulates an approach signal like an ILS (LOC/GS) to drive the autopilot during a GPS approach with LNAV/LPV capability. While the ILS mode is active, the EFIS system expects ARINC429 labels (localizer deviation, glideslope deviation and ILS energizer information). In case of a SBAS (LNAV/LPV) capable GPS approach will be executed, the “Approach Active Discrete” enables the LPV/VNAV-Converter to supply the EFIS system AP-NAV-Input with ILS comparable GPS approach data. At the same time, the LPV/VNAV -Converter switches the DME information into GPS distance, speed and time information, shown on the EFIS display.