Create a SysML diagram using Gaphor that models the flow$-$based behavior of a simple aircraft.

The aircraft should have the following functionality:

Flight planning

Pre$-$flight check

Takeoff

In$-$flight navigation

Landing

The diagram should include the following elements:

Blocks for the aircraft, flight computer, navigation system, and flight controls

Activities for the different actions $($e$.$g$.$ flight planning, pre$-$flight check, etc.$)$

Constraints to specify the conditions under which certain actions occur $($e$.$g$.$ the flight

computer only allows takeoff if the navigation system is properly calibrated$)$