Royal Naval Air Station Lee-on-Solent (HMS Daedalus) was one of the primary shore airfields of the Fleet Air Arm. First established as a seaplane base in 1917 during the First World War, it later became the main training establishment and administrative centre of the Fleet Air Arm. Situated near Lee-on-the-Solent in Hampshire, approximately four miles west of Portsmouth on the coast of the Solent at grid reference SU560019, the establishment has now been closed down.