The picture above is of Imperial Airways' flying boat "City of Athens" being towed by a launch loaned by White Star Line on the river Mersey, September 1928.
It was operated from 'The Liverpool Marine Aerodrome' off Rock Ferry by the Mersey Docks and Harbour Board - this experimental flight to Belfast was the only known service.
The Short S8 Calcutta flying boat G-EBVH had a crew of 2 and could carry upto 15 passengers.
The inaugural flight on Saturday 22 September 1928 carried 12 distinguished guests who were treated to a civic luncheon on arrival at Belfast.
The first week went successfully so it was decided to continue into a second week. However the aircraft was damaged and returned to Southampton for repairs; it never returned, instead it was used on the Channel Islands service - so came the end for the experimental service.