How can I overcome my fear of flying? My fear is I will have a panic attack on the plane bc im afraid of heights and I wont be able to get off.

For phobias. consider Cognitive Behavioral Therapy, Behavior Therapy, Psychotherapy, Exposure therapy (imaginal exposure therapy, systematic desensitization, flooding, prolonged exposure therapy, in vivo exposure therapy) or hypnosis as possible options. Psychotropic medications are sometimes indicated as well.
VRT for Phobias. Fear of flying s very common. Try to locate a therapist who uses Virtual Reality Therapy(VRT) for phobias. The research is very positive on the use of VRT for fears and phobias. Take a look at these sites: www.psious.com, www.limbix.com or www.virtuallybetter.com. .
Panic Disorder. I feel your distress. Have step by step travel to go to heights to those places which are Beautiful. Work your way up, to take Train from Jasper town in your Country to top of Jasper National Park and Feel the WONDER! Take airplane trips of 1hour duration, after seeing Psychiatrist and taking Ativan or Xanax (alprazolam) before getting in the airplane; longer journey with medication in the plane if needed.