Although the first entry in Seaplane Squadron records is dated 16 February 1934, the official history of the Royal Australian Air Force (RAAF) between the wars refers to the unit as having been in operation when Australia acquired two Supermarine Southampton flying boats, which entered service in January 1928.

[5] On 22 June, one of the flying boats was overturned by strong wind on the Torrens River en route to meet the four Southamptons of the Royal Air Force's Far East Flight near Adelaide.

[8] From June 1935 to February 1936, a Southampton was employed to map the Darwin–Sydney section of the Empire Air Mail Scheme route; its survey work ultimately took it to New Guinea and around the Australian continent.

[1][9] Seaplane Squadron undertook search-and-rescue work with both the Southamptons and Supermarine Seagulls; the former were involved in the abortive search for the airliner Miss Hobart, a de Havilland DH.86 that vanished in Bass Strait on 19 October 1934.

[11] In October 1929, Seaplane Squadron received a locally designed amphibian, the Wackett Widgeon II; it crashed into the sea off Point Cook on 6 January 1930, killing all three occupants.

[12] Another Wackett design, the Warrigal II landplane, was fitted with floats and assigned to Seaplane Squadron in September 1932 for trials and possible use as a trainer and patrol aircraft; it was considered successful in the latter role but maintenance issues led to its disposal in July 1933.

In May 1934, one of these was flown to Darwin, Northern Territory, where it was fitted with floats and undertook reconnaissance and survey work in cooperation with HMAS Morseby, before being converted back to a landplane and returning to Point Cook in July.