The Aeromarine Model 40 was a two-seat floatplane trainer aircraft serving the United States Navy. The aircraft was produced by the Aeromarine Plane and Motor Company of Keyport, New Jersey, and had already made a name for itself by supplying the US Navy with its first carrier-landed aircraft in the Aeromarine Model 39. Whereas the Model 39 could be utilized as a land-based and floatplane aircraft equally (requiring the conversion of the undercarriage to suit each task), the Model 40 was a dedicated flying boat using wing panels and struts of Model 39 on a new flying boat hull.

One or two 40-F may have been tested by the Coast Guard.

Design was conventional for the time, consisting of a contoured boat-like hull fitted to a boxy fuselage mounting a large unequal-span biplane wing configuration. Single pontoons were fitted as outrigger floats, one per each lower wing assembly. The upper and lower wing assemblies were joined by parallel struts making up two bays and fitting appropriate cabling. The student and instructor sat side-by-side just behind the nose and in front of the wing structure in an open-air cockpit. The view was superb from this position with their forward views protected by two simple curved windscreens. The empennage was adorned with a conventional large-area vertical fin and horizontal tailplane system showcasing rounded edges. The powerplant was placed within a strut configuration supporting the upper and lower wing assemblies at mid-span. The engine was situated well above and just behind the pilots, sporting a two-bladed pusher propeller system powered by a single Curtiss OXX-6 series V-8 water-cooled engine producing an output of roughly 100 horsepower (some later Model 40’s were known to fit a Hispano-brand engine in its place). Performance from this pusher arrangement allowed for speeds of up to 71 miles-per-hour with a service ceiling of nearly 1,900 feet. Endurance was listed at about 4.5 hours of flight time.

The Model 40 was designed and built in response to a 1918 Navy Department order for a two-seat seaplane trainer, 200 Model 40’s were initially ordered by the US Navy in 1918.

Very similar in general design to the Curtiss model MF trainer, which it was intended to augment, serialed A5040-5089, fifty 40-Fs were built.

Although the first civil model 40 may have flown in 1918 with a 150 hp Aeromarine U-8 engine, the first documented flight of the Navy model 40F occurred in 1919. When World War I ended, the original Navy order for 200 aircraft was reduced to 50, and all examples were delivered after the armistice. The model 40-F was operated by the US Navy as a trainer. The end of the war in November ultimately signified the end of the production contract, leaving only 50 Model 40 examples produced. Model 40’s still managed to see service in the post-war world solely with the United States Navy. Overall, their operational use proved the airframe too fragile for the constant rigors of water-born operations, to which these results helped in future American flying boat designs. During service, some model 40Fs were reportedly refitted with 150 hp Hispano-Suiza engines to improve performance and payload.

The civil versions (40 and 40B, 140 hp Hispano-Suiza engine; 40C, 150 hp Aeromarrine engine; 40L 130 hp Aeromarine L engine; 40T, 100 hp Curtiss OXX-6 engine; and 40U, 100 hp Aeromarine U-6 engine) were produced in 1919 and sold for around $9000 each. An estimated six civil models were built.

The Aeromarine Model 40 was further developed into the Model 41 to which some existing Model 40’s were converted to this newer design.

The Aeromarine 41 flying boat were conversions of Model 40s mentioned in 1922.

Gallery

40
1919
Engine: Hisso, 150hp
Span: 48 ft 4 in
Length: 28 ft 11 in
Seats: 2
Speed: 85 mph
New price: US$9,000

40
Engine: Curtiss OXX-6, 100 hp
Prop: 2 blade wooden fixed pitch
Upper wingspan: 48 ft 6 in
Length: 26 ft 11 in
Empty weight: 201 lb
Loaded weight: 2592 lb
Max speed: 71 mph at SL
Ceiling: 3500 ft
Range: 250 mi

40-B
1919
Engine: Hisso, 150hp
Span: 48 ft 4 in
Length: 28 ft 11 in
Seats: 2
Speed: 85 mph
New price: US$9,000

40-C
1918
Engine: Aeromarine U-8, 150hp
Seats: 2

40-F
1919
Engine: Curtiss OXX-6, 100hp
Wing span: 48 ft 6 in / 14.80m
Length: 28 ft 11in / 8.8m
Height: 11.48ft / 3.50m
Empty Weight: 2,061lbs / 935kg
Maximum Take-Off Weight: 2,590lbs / 1,175kg
Maximum Speed: 71mph / 114kmh / 62kt
Maximum Range: 314miles / 506km)
Service Ceiling: 1,903ft / 580m)
Seats: 2
New price: US$8,100

40-L
1918
Engine: Aeromarine L, 130hp
Seats: 2
Speed: 80 mph
Payload: 560 lb

40-T
1919
Engine: Curtiss OXX-6, 100hp
Seats: 2

40-U
1919
Engine: Aeromarine U-6D
Seats: 2