What's average?
If passengers are willing to tolerate 1/2 of 1 gravity of acceleration for 7 minutes, an airplane would be able to accelerate from 0 to 4500 mph, fly between NYC & London & decelerate to 0 in about an hour. Seats that rotate from forward to rearward facing would be needed. Ideally, they would tilt as well, but hardly a technical challenge either way.