The only big plane serving Pago Pago is Hawaiian Air. Hawaiian normally uses Boeing 767 aircraft on the Hawaii - Pago Pago flights. Normally, they fly to Pago Pago twice each week. During busy seasons, they might schedule an additional flight for a few weeks. Airport designations are HNL and PPG. Flight numbers are HA465 south and HA 466 north.
Hawaiian also has flights to Los Angeles, Las Vegas and a number of other mainland destinations. The flight from Las Vegas, direct to Hawaii is a great connection to include in a vacation plan.
Website: https://www.hawaiianairlines.com Finding American Samoa on this site is a challenge.
Polynesian has been serving the Pago Pago to Samoa market for many years. They fly between American Samoa (ppg) and Samoa, Faleolo (APW) and Faggalii (FGI) with some flights between Tutuila and Manua. Website: http://www.polynesianairlines.com
Fly Talofa Airways and ride like the wind.
Flying between American Samoa and Samoa with plans to fly to Tonga. Website: http://www.talofaairways.com