FMC Route To/From Same Airport

intjmastermind

The FMC is not allowing me to enter the same airport as both the origin and destination waypoint. It returns an error that I am entering a duplicate waypoint and will not let me proceed. If I wanted to practice ILS or RNAV approaches at the same field I’m departing from, what’s the best way to put that in the FMC?

jmarkows

Can you start by entering just the airport and then adding an approach to it?

Failing that, can you add the airport, manually add an approach waypoint (IAF or similar), then the airport again and load the approach?

intjmastermind

Some results from experimenting at KSMO...

The FMC won't allow you to have a single waypoint flight plan. It requires at least two waypoints.
You cannot repeat the same waypoint twice in a row, but you can have a waypoint twice in a flight plan as long as there's a different waypoint in between. i.e. KSMO - SMO - KSMO.
Starting the flight plan from a non-airport waypoint is permissible. i.e. SMO-KSMO or DARTS-KSMO. The second allowed me to load the RNAV 21 approach from DARTS iaf without duplicating the DARTS waypoint. Probably the better option if you know in advance which approach you want to load.

However...

The DIRECT page will allow you to select a close by airport even with an empty flight plan. Selecting KSMO from the DIRECT page generates a flight plan ----/KSMO, which then does allow you to load any approach without needing a "junk" starting waypoint. This might actually be my preferred way of doing it now.