We flew from Manchester, NH to Seattle, WA on 10/3 and 10/9. I have a 7 year old and a 2.5 year old. Both were fine. We are very blessed to have a clear definition of good and evil. She, the 7 year old, understands that those planes were taken over by evil men and the evil men died on the planes. Also, she understands that in the world today there is good and there is evil still. And that the President and the military are protecting us from any more evil men. That is the first point of confidence that she can rest on.
The second point is that she has a firm grasp of where you go when you die. Jesus Christ came that she specifically may live, along with anyone that accepts His free gift of salvation through grace. She has taken a hold of that truth and holds it close to her heart.
My wife was initially hesistant to board the flight, but she also knew the above 2 points and knew that if something dreadful happened we would be with the Lord together as a family.
It seems today that flying and all the other scares that are out there, remind people more than ever of their fears. Mostly their fear of death - that is a fear most do not want to face.
It is my point that kids read things honestly, if you are afraid and do not know why then they will be afraid as well. If you are confident and know the deep truths of life, they will be confident as well.
I hope the trip goes well and your children and yourself find the peace for the flights.
Tom.