RedactedNarrative: Operator 1 was operating vessel 1 while cruising on plane. As operator 1 was enroute to a gas dock an unknown vessel cut in front of vessel 1. This caused operator 1 to let off the throttles. When operator 1 let off the throttles passenger 2 fell forward impacting vessel 1. Passenger 2 sustained injuries from sudden slowing of vessel 1. There was no injuries from any of the occupants on vessel 1. There was no damage to vessel 1.