14:06 Basically sonic-boom is a sort of unwanted noise generated due to an object being faster that the speed of sound hence the name, And the MACH 2 at 14:18 was to refer the plane is twice as fast when compared with speed of sound; things like mach, and raynold numbers are unit less parameters used by engineers to compare different properties as far as my understanding goes. for some of you with engineering background who took fluid mechanics course this should be familiar to you.
Seattle Museum of Flight is one of the best museums in the United States. I wish you could go there with the person who has enough knowledge about the museum. Also, he gives you a lot of wrong information.
They only used 747 to transport charger/space shuttle. It lands just like plain & it takes off just like the movie Apollo. Again 747 was to transport it from place to place that is bcz of chargers speed. B