Constructed of stainless steel. For a flying boat, this at least made some sense, avoiding any corrosion problems. The aircraft was certainly durable: this four-seat prototype, preserved at the Golden Wings Musem in Minnesota, was still reported to be flying once a year in 2015. Five F-5 five-seaters were also built. Photo by: Rudy Arnold / Smithsonian Institution

No doubt, the pilot is Harold S Johnson of Illinois, the 'King of Fords'. Check out online videos to admire his really impressive Tri-Motor aerobatics. Soho Oil sponsored him but here the titles are not clear. Tri-Motor c/n 4-AT-42 was later registered as N9610. Photo from: Grand Rapids Public Library

'Holder, inverted speed record'. The Howard DGA-4 Mike and DGA-5 Ike were very similar. The DGA-5 originally had small tandem wheels within its wheel pants but this was changed. The pilot is blocking the Fordon-Brown National Air Show titles. Photo from: Grand Rapids Public Library

The New York - Bermuda service inaugurated by Pan Am and Imperial Airways in 1937 was aimed at tourists, but Bermuda was planned to become an important stop in the upcoming transatlantic flying boat traffic, hence the large new building in the background, not yet marked 'Bermuda Airport - Imperial Airways' here. Darrell's Island is a small islet so onward boat transport was necessary - no effort was spared to make passengers seasick as well as airsick, it seems! Photo from: University of Miami