IMHO, I wonder if the chopper being black may have been a problem with the Cessna pilot not seeing it, it being a routine trip up the Hudson, would it not be better if it were painted in a more prominent colour?
The Netherlands airforce painted their Pilatus PC-7 basic trainers black a couple of years ago, because research had shown that black aircraft are
better visible against a daylight sky than other colours.
Regards,
Frits