True, however the otter does not require that. It is allowed to operate with 10 passengers in commuter operations. This is why many of the Alaska operators and my company prefer them to the Caravan, because of that extra revenue seat.
I don't remember the specifics, but is something to do with them being type certified before the 9 pax rule was written i think. They are grandfathered in and allowed to operate with 10 pax without an ATP or second pilot. My company and several in Alaska do this as SOP.
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