J.Wegg General Dynamics Aircraft and Their Predecessors Since 1912 (Putnam)

S-4 Series

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   Following tests at Cayuga Lake with the prototype S-4 fitted with twin floats, six S-5s (BuA-757/762) were built in 1918 for the Navy. These were basically S-4Bs with triple floats copied from the Sopwith Baby and were used at NAS Dinner Key, Miarni. At least one (A-758) flew with a revised rudder which was taller, but of reduced span.
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G.Swanborough, P.Bowers United States Navy Aircraft Since 1911 (Putnam)

THOMAS-MORSE S-5

The six S-5s (A757-A762) were seaplane versions of the S-4B trainers built for the army and were delivered in 1917 to the Navy in Army olive drab colouring. The arrangement of the three wooden floats was copied from the British Sopwith Baby, which the S-5 closely resembled. Single-seat scout seaplanes did not work well for the Navy and further development was abandoned. Power plant, 100 hp American-built Gnome rotary engine. Span, 26 ft 6 in; length, 22 ft 9 in; gross weight, 1,500 lb; max speed, 95 mph.

Jane's All The World Aircraft 1919

THE THOMAS-MORSE S.5 SINGLE SEATER SEAPLANE
  
   Designation of six S.4B seaplanes used by the US Navy from 1917-18.
  
Type of machine Single-seater Seaplane.
Name or type No. of machine S. 5.
Purpose for which intended Training.
Span 26 ft. 6 in.
Overall length 22 ft. 9 In.
Maximum height 9 ft. 7 In.
Total surface of wings (inc. ailerons) 240 sq. ft.
Total area of fixed tail plane 16.8 sq. It.
Area of elevators 22 sq. ft.
Area of rudder 8.5 sq. ft.
Area of fin 3.5 sq. ft.
Total area of ailerons 30 sq. ft.
Engine type and h.p. 100 h.p. Monosoupape Gnome.
Airscrew, diameter and revs. 8 ft., 1250 r.p.m.
Load per sq. ft. 6.25 lbs.
Weight per h.p. 14.3 lbs.
Tank capacity in hours. 3 hours.
Tank capacity in gallons 30 galls.
Performance.
   Speed low down 95 m.p.h.
   Landing speed 50 m.p.h.
   Climb
   To 5,200 feet in minutes 10 minutes.
   Total weight of machine loaded 1,500 lbs.