The mere was used for seaplanes because it was close to the sea and because its still water made it easier to launch the planes.

A report submitted to the Air Ministry in 1915 detailed possible landing sites for aircraft along the Yorkshire coast, suggesting the use of racecourses and giving Beverley, Redcar and Scarborough as examples.

The report also mentions the ideal scenario at Hornsea Mere, where the still water was perfect for launching seaplanes, and was only 1,500 yards (1,400 m) from the sea.

[3] The seaplane station occupied a westward-facing peninsula into the mere from the eastern shore, covering 6 acres (2.4 ha), known as Kirkholme Nab.

[16] With the formation of Squadrons at Hornsea Mere, it was expanded into a full base, no longer a sub-station of Killingholme, and it was finished with some more permanent buildings.

[17] In a survey conducted by the RAF in 1918, the base was listed as having at least thirteen structures, two slipways and a compass rose.

[20] This was a circular device which allowed for the calibration of the aircraft's onboard compass in the days before GPS systems became available.

[21][22] Until its closure in 1998, RAF Cowden range was approached from the north west by pilots using the buildings on Hornsea Mere as a waymarking point to guide them in.