Chris - after much virtual tramping the Google Earth, I can reveal the location in the background as:
North German Lloyd Pier No.2, Hoboken, New Jersey.
So it is on arrival at New York, therefore almost certainly on the Cie Gle Transatlantique's SS Liberte in 1957; which does ring true, as the Liberte would have docked on or around Pier 53 in Manhattan, on the east side of the Hudson River (Hoboken is on the opposite (W) bank). The picture very much foreshortens the perspective of the pier jetty, but the buildings in the background in the pictures below seem, in my opinion, to match those in your photo. First pic is in 1914, to show the architectural similarity; second is in 1954, after the piers were repainted or re-clad; third shows the Liberte docking in Manhattan in 1950. The North German Lloyd piers are no longer in existence, but were located at the river end of 3rd Street, Hoboken. Phew, mystery (I think!) solved!!
To summarise, therefore:
Date: c. 11th Jun 1957. Early morning (judging by direction of shadow). (those with access to the passenger lists will be able to determine the exact date of arrival)
Place: Hudson River, New York aboard the Companie Generale Transatlantique's SS 'Liberte'.
Rank: Pilot Officer.
Reason: Docking in Manhattan prior to onward travel to RCAF Station Centralia, Ontario, Canada to begin National Service flying training as part of the NATO Flying Training Plan.