On June 27, 2019, at about 0945 Alaska daylight time, a float-equipped, de Havilland DHC-2 (Beaver) airplane, N94DC, sustained substantial damage following a loss of control during landing at the Ketchikan Harbor Seaplane Base (5KE) Ketchikan, Alaska. The airline transport pilot and four passengers were not injured. The airplane was registered to V2 Aviation LLC, and operated by Pacific Airways, under the provisions of 14 Code of Federal Regulations Part 135. Visual meteorological conditions prevailed and company flight following procedures were in effect. The flight departed the dock at Ketchikan International Airport (PAKT) at 0941 destined for 5KE. According to the pilot, after providing the passengers with a preflight safety briefing, he departed the PAKT airport dock for the short repositioning flight to the company's harbor side dock. After departure, he flew the standard west route, turned back overhead the airport dock, and then turned inside of Pennock Island for final approach to the harbor. Upon touchdown, the airplane skipped, and the right float dug into the water. The airplane water looped, nosed down and began to submerge. After all motion had ceased, he secured the magnetos, assisted the passengers with their life vests and evacuation, and then evacuated the airplane himself. A Good Samaritan fishing boat responded to the scene and assisted with the rescue of the airplane's occupants. The pilot reported that there were no preaccident mechanical malfunctions or anomalies that would have precluded normal operation. A video recorded by a cruise ship passenger captured the accident sequence and revealed that the airplane was landing parallel to an ocean swell and touched down in a relatively flat pitch attitude. After touchdown and encountering the swell, the airplane veered to the left, water looped, nosed down and began to submerge. Water Flying Concepts, Second Edition, by Dr. Dale De Remer is an advance text on wilderness water flying and states in part: The seaplane is very directionally stable as long as it is landed so that its center of gravity is forward of its center of rotation. The seaplane center of rotation in the air is its center of gravity, and on the water it is the center of the wetted side area of the float(s). This is difficult to visualize, as it changes with the speed and attitude of the aircraft on the water. It can be considered to be close to the center of buoyancy. The main thing to remember is to keep the center of rotation aft of the center of gravity. Keep the center of rotation aft, period, until the aircraft has slowed and settled off the step. In the recommendation section of the NTSB Accident/Incident Reporting Form 6120.1, the operator recommended the following three changes to their operations: More extensive training for new pilots on aborted and glassy water landings. No longer allowing first year pilots to execute short approaches into the harbor. Aircraft to refuel at the harbor, prior to passengers boarding at PAKT airport dock for their flights. The closest weather reporting facility is Ketchikan International Airport (PAKT), Ketchikan, Alaska. At 0953, a METAR from PAKT was reporting in part: wind, 320° at 5 knots; visibility, 10 statute miles; sky condition, clear; temperature, 70° F; dew point 57° F; and an altimeter setting of 29.93 inches of mercury.