Page 5-38 400W Series Installation ManualRev. G 190-00356-025.6 Flight ChecksAll system functions that cannot be adequately tested on the ground will require a flight test. Even if allfunctions can be verified on the ground, a flight test is recommended as final installation verification.Verify system operation as described in the following sections.NOTEThe analog deviation (LEFT/RIGHT and UP/DOWN), TO/FROM, and FLAG (lateraland vertical) outputs to a CDI or HSI should be verified in flight with potential sources ofelectrical noise such as autopilot, flaps, gear, heater blowers, etc. operating. Lateraldeviation and flags may be checked with either GPS or VOR/ILS, and vertical deviationand flags must be checked with Glideslope. Verify that the flags are hidden at the correcttimes, and that the flag is in view at the correct times.5.6.1 GPS Flight Check1. Verify that GPS position is not lost during normal aircraft maneuvering (e.g. bank angles of up to30 degrees and pitch angles associated with take-off, departures, approaches, landing and missedapproaches as applicable). If GPS position is lost, a “LOSS OF GPS NAVIGATION” messagewill be displayed.2. Enter and activate a flight plan on the 400W Series unit. Fly the flight plan and verify that thedisplay of flight plan data is consistent with the CDI indication (deviation, TO/FROM…) in thepilot’s primary field of view.5.6.2 VHF COM Flight Check (GNC 420W and GNS 430W)After the installation is complete, a flight test is recommended to ensure satisfactory performance. Tocheck the communications transceiver, maintain an appropriate altitude and contact a ground stationfacility at a range of at least 50 nautical miles. Contact a ground station in close proximity. Press theCOM volume knob to select manual squelch and listen for any unusual electrical noise, which wouldincrease the squelch threshold. If possible, verify the communications capability on both the high lowand mid bands of the VHF COM band. It may be required by the governing regulatory agency to verifyoperation of the COM transmitter and receiver at the extents of a ground facility’s service volume (e.g.,FAA AC 23-8A).5.6.3 VOR Flight Check (GNS 430W)1. Tune a local VOR station within 50 miles.2. Verify the audio ident and voice quality and verify that no objectionable electrical interferencesuch as magneto noise is present.3. Verify the Morse code decoder IDs the station (95% probability).4. Fly to and from the station.5. Verify NAV flag, TO/FROM flag, and CDI are operational.6. Record accuracy in System Log (see manual).It may be required by the governing regulatory agency to verify operation of the VOR receiver at theextents of a ground facility’s service volume (e.g., FAA AC 23-8A).
