The first aircraft to operate in Bergen was a demonstration flight by Carl Gustav Cederström on 25 September 1911. The first airport in the Bergen area was Flatøy Air Station, built by the Royal Norwegian Navy Air Service on the island of Flatøy. The water aerodrome was established in 1919; it remained in use until 1940. Norway's first scheduled airline service was started by Det Norske Luftfartsrederi between Bergen, Haugesund and Stavanger in 1920, and operated out of Bergen Airport, Sandviken, a water aerodrome just north of the city center. The aerodrome became the Bergen base for both Norwegian Air Lines and Vestlandske Luftfartsselskap. Planning of an airport with an airstrip took place during the 1930s. A series of public institutions made various reports between 1931 and 1938, which largely recommended Flesland as a location, which was at the time located in the then independent Fana Municipality. The main alternative was Herdla, an island northernmost in Askøy Municipality, which was first recommended in 1933. The main disadvantage with Flesland was the topography and that it would not be possible to build longer runways than 800 and 850 meters (2,620 and 2,790 ft), respectively. A municipal committee recommended therefore in 1938 that Herdla be chosen, to be jointly financed by the state and the municipality After the German occupation of Norway, the Wehrmacht started looking for a location for an airstrip. They were partially in need for a counteraction against British raids and in part in need to protect German ship traffic. Four locations were considered: Nesttun, Haukåsmyrene in Åsane, Flesland and Herdla. The choice of Herdla was taken after a German bomber emergency landed in a field and was later able to take off from there. Herdla received two runways, the longest 1,000 meters (3,300 ft) long. The Civil Aviation Administration (CAA) started working on plans for an airport for Bergen in 1947. Herdla was by them seen as the prime candidate, again based on the poor topography around Bergen. The CAA recommended that Herdla be chosen and that the two runways be expanded. However, its director, Einar Bøe, was skeptical to the Herdla plans, citing the lack of possibilities to extend the runway past the initially proposed 1,500 meters (4,900 ft) and the long travel distance from Herdla to the city. At the time there was no bridge either from Herdla to Askøy nor from Askøy to the mainland, nor was there a road across the island. Transport would therefore have to be carried out from Bergen using a ferry. The Minister of Transport and Communications Nils Langhelle from Bergen supported Bøe's concerns and recommended that Parliament place construction of an airport serving Bergen on hold. Engineering reports were made of both Herdla and Flesland in 1950 and 1951. Previous investigations of Flesland had concluded that the length of the runway was limited to a small valley which is located at about the middle of the current runway. The new report proposed connecting the proposed area to a larger area to the south of the valley, which was at the right elevation. This would allow for a 3,000-meter (9,800 ft) long runway. A political concern was the high cost of constructing a new airport. By 1950, land airports had been built for Oslo Airport, Fornebu, Stavanger, Trondheim and Kristiansand. This was supplemented with SAS deciding to terminate the services to Oslo and instead provide a feeder service to Stavanger. Alternatives were launched by two competing airlines: Braathens SAFE proposed a minor upgrade to Herdla which would allow them to operate with their de Havilland Heron aircraft. Widerøe on their side proposed using their Consolidated PBY Catalina flying boats, but these proved to expensive. At the same time the Royal Norwegian Air Force stated looking at Flesland as a suitable air station. Military engineers surveyed the area and concluded that it was well-suited for military purposes.