You have a flying phobia. Usually simple to treat one single session with the right type of therapist. You need someone to help you remove the phobia. A good Hypnotherapist with NLP training should be a good start. There is no need to go into your past or overthink this. A phobia cure works by pulling apart the structure that hold the phobia in place. Its really just emotional baggage paired to an external trigger. In this case flying.