Captain Airclues has it in one. The picture was taken by my mother on a flight from Diego Suarez in the latter half of 1970 while the airport was still under construction. I was there that December and I remember a US Albatros (0-17163) landing in the sea beside the runway and taxying up to the apron afterwards with mail and supplies for the US Satellite tracking station there.
Over to you Captain Airclues.