This was the layout when I joined Pan Am in May 1961, working in telecoms upstairs from the International departure lounge in the building located by the pointer from 'London Airport North'
In the Central area the 'South East Pax Bldg' was used for domestic flights and later became Terminal 1
In early 1963 we re-located to a building adjacent to the Pan American hangar which does not exist on the map (bottom right) at this time, located between the small access road to the apron and the pointer line from the title, so this makes the map pre-1962 at least.
Incidentally, runway No 2 (NE-SW near BOAC hangars) was used for cross-wind landings from the NE but FD crews had to be aware when lining up for landing not to confuse the visual cue of the large gasometer at Southall with the similar large gasometer at Harrow which would lead to landing at Northolt airport, as a PanAm B707 skipper managed to do
Said gasometers later gained large white lettering NO and LH.
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