SomeGuyOnTheDeck,
And to second what protectthehornet wrote:
Basic floatplane skills
Calm conditions known as glassy water are the most deceptive phenomenon known to the float pilot. It is an
outright dangerous surface to land on if not completely comfortable with the procedures. The height above the
water surface is impossible to estimate correctly, making it extremely difficult to judge the final few feet. Many
experienced float pilots have been caught up in the deception. The most dangerous glassy water condition is
when the water surface is clear. The pilot will be looking at the bottom of the river or lake and not at the surface of
the water.
They had a lot of visual clues in the Hudson River to complete their water landing "adequately"