It could be said that the birth of Naval Aviation took place within five miles of the Royal Naval Air Station Portland when, in 1912, Lieutenant Samson launched his Short Biplane off the cruiser HMS Hibernia. As he overflew what is now the runways the picture would have been somewhat different - no fuel tanks, no hangars, and definitely no runway. The main administration building was then the Naval Base Canteen, and Victoria Gate was the site of Portland railway station. Naval Aviation has been as much a part of Portland as the quarries and prisons for the best part of the century.

World War 1 saw the obliteration of much British coastal shipping by U- boats, leading to the Admiralty establishing a chain of Royal Naval Air Service seaplane bases around the coast of Britain. The harbour at Portland was an obvious choice, and on 28 September 1916 a flight of four Short Floatplanes was formed and housed close to the current site. HMS Serepta, Portland's first shore establishment, was built on the Isle in 1917 as increasingly the harbour was used by the surface fleet.

In September 1939, 772 Squadron was formed as a Fleet Requirements Unit, operating Swordfish Floatplanes in a variety of tasks including target towing. With the fall of France early in the second world war, the Naval Base at Portland became a prime target for the Luftwaffe, and the continued presence of the Anti-submarine School was infeasible. The school moved to Cambeltown in July 1940, and took 772 Squadron with it. For the remainder of the war the seaplane facilities at Portland operated on a care and maintenance basis only.

Aviation returned to Portland in 1946 when the Anti- Submarine School moved south again, and the first helicopters appeared in the form of the Sikorsky R-4B. Being used for development work from the Naval Base slipway, these helicopters paved the way for the use of helicopters in the fleet. Success with these trials, and with aviation activities on the increase, the Admiralty decided to replace fixed-wing anti submarine aircraft with helicopters, heralding a major building programme at Portland.