. "HMS Sarepta"@en . "RNAS Portland was an air station of the Royal Navy from 1917. The site was first built in 1917 as HMS Sarepta within the confines of Portland Harbour as a seaplane base; the aircraft operating from the base's slipways. In 1959 it became RNAS Portland (HMS Osprey)"@en . . . . "RNAS Portland was an air station of the Royal Navy from 1917. The site was first built in 1917 as HMS Sarepta within the confines of Portland Harbour as a seaplane base; the aircraft operating from the base's slipways. In 1959 it became RNAS Portland (HMS Osprey)"@en . .