Chinook is much much bigger, has 4 landing gears instead of 3 like the Seaknight. Engines are mounted externally on the Chinook and farther aft instead like the Seaknight.
The buldges on the Chinook by the way house the fuel tanks.
Surprises me how fast that sea knight came in. Must of been showing off or something. Usually they are directed in more slowly. Especially on such a small ship.