There's an Arnold H. Nilsen listed in the crew list for Nidarnes - see [www.warsailors.com] This could be him, as you'll see, survivors were picked up by an American ship.

I looked for other Arnold Nilsens or Henrik Nilsens etc. and found the names in crew lists for the following ships:
Oslofjord [www.warsailors.com]
Pericles [www.warsailors.com]
but these don't fit your description as well.

Siri