Amos
Your photos are fantastic, and brought back some very good memories. My first long haul from Heathrow was on the South African Airways Boeing 707-244 to Johannesburg via Isla do Sal. That was June 1969.
Earlier flights were in the Air France Caravelle to Paris and the Swissair Coronado to Geneva. Another Air France flight to Paris was in their Super Constellation.
I recall the SAA 707 had a ventral fin, something to do with longitudinal stability at the gross weights being used by SAA. In those days they were obliged to "go round the bulge".
Somewhere in my archives I have slides taken during the departure from Heathrow in the SAA 707, I was seated on the left hand side just in front of the engines. I also took pics as we arrived in Jo'burg, typical winter weather blue sky brown earth.