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Dont know if this helps -
Regarding flying boat movements from Southampton - Imperial Airways had their terminal bldg at an area described as 'Berth 108 New Docks' during
pre-war years - later moving to 'Berth 50 Old Docks'. - where they continued operations up to 1950 - Thereafter Aquila Airways continued
f/b operations until 1958.
Slightly offthread - in 1937/ 8 Shorts were operating their Short Mayo composite flying boat service on the River Medway at Rochester. This was an air mail service to the USA whereby a float plane was mounted piggy back style onto another Short flying boat - due to limitations
of sufficient fuel - with a/c seperation somewhere off Ireland.
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