During the opening sequence TC's MD500 registration number is first N58243, but when he lands on the ship it is N1095A.
During the opening sequence, the sound of TC's MD500 helicopter in flight is wrong. Apparently the sound of a Bell JetRanger was dubbed on to the soundtrack. The MD500 has a much smoother "humming" sound because of the 4 or 5 bladed main rotor, and sometimes is indistinguishable from a fixed wing prop driven aircraft.
As they're nearing Oahu (50min away) T.C. points out to Joey that, "If you look close you can see the big island at about 3 o'clock" and Joey responds, "Oh yeah I can just see it." But at that moment Joey is looking at 1 o'clock, not three. And when the camera shows where Joey is looking it's at 12 O'clock.