Mmm, where is the Aggregate and Aggregate roots here ? This is only Data Model... Not Domain Model.
Aggregate is a cluster of items (Domain Object) that are gathered together, and Aggregate Root are the entity root... (If you consider the Flight Aggregate encapsulates Seats, Location... The Aggregate Root should be Flight entity).
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You have to ignore the persistent. In your app you can have many aggregate it depends in your Domain, maybe Flight is an Aggregate and Company another one ;), don't confuse entity and Aggregate...