According to historical accounts, the 1926 aerial survey of the Tongass National Forest was dispatched from the U.S. Naval Air Station in San Diego with a crew of 114, including 39 in the aviation-photography division and 75 on the U.S.S. Gannet seaplane tender.
The expedition was based in Ketchikan from June to early August and then moved to Juneau until leaving in September.
The expedition included three Loening OL-4 and one OL-2 amphibian planes and equipment such as T-1 three-lens mapping cameras, two K3A single-lens mapping cameras, an Akeley 35mm motion picture camera and a Fairchild K-31 single-lens mapping camera.
The Gannet towed a barge with repair and supply shops as well as photography dark rooms. It also housed carrier pigeons for emergency communication. The planes carried food rations, emergency kits, guns and other survival equipment.
After each flight, the film was processed and a print of each negative was checked by a federal geologist.
The 1929 expedition also embarked from San Diego with the U.S.S. Gannet and four OL-8A amphibians. It boasted some better camera equipment and mostly mapped the northern part of the Tongass. The expedition was based in both Juneau and Ketchikan.
During the 1929 expedition, the planes photographed about 13,000 square miles and the Navy produced 5,600 prints, according to historical accounts.
This expedition discovered a number of lakes on the eastern shore of Taku Inlet, according to the accounts.
In 1932, the Alaska Aerial Survey began a several-year project mapping the Aleutians.