1918 Otto Timm Trainer biplane, T-18
An article from the Flying Pioneers Biographies by Harold E. Morehouse describes a "rugged training biplane built to meet government requirements". This document came from the NASM. Development of this aircraft was stopped after the Armistice of First World War I, November 1918. I think the following photos are of this aircraft.
The aircraft appears to be built similar to a Curtiss JN-4D parts. The fuselage is designed to separate just aft of the rear cockpit. Otto Timm built an engine for this aircraft; it is a six cylinder radial. From the following photos it appears to have two exhaust ports per cylinder, facing forward with no exhaust manifold.
The registration, 112, can be seen in two of these photos. According to the registration data on Areofiles, this was assigned a Curtiss JN-4D serial number 100. I doubt that this serial number is a correct Curtiss JN-4D number. Perhaps it is a number assigned by Timm to his project.
More details can be found in the following two pages from Aerial Age Weekly, 19 May 1919
125 hp 6 cylinder Timm engine
Smithsonian National Air and Space Museum (NASM 00094189)
Smithsonian National Air and Space Museum (NASM 00094190)
Smithsonian National Air and Space Museum (NASM 00094192)
Smithsonian National Air and Space Museum (NASM 00094194)
Engine details
Engine discription from Aerial Age Weekly, May 19, 1919
The O. W. T. engine is a six-cylinder radial type air-cooled. rated 125 H. P. at 1475 R.P.M. Bore 5", stroke, 6". The weight, complete ready to run is 325 lbs. Cylinders are machined from solid steel forgings. Cylinder heads are of semi-steel castings, and are screwed and welded into the cylinders. Each cylinder is attached to the crankcase by means of 8 studs. Pistons are of cast iron for strength and cooling on each piston. The heads are flat, and well webed. Three double seal rings are used. A double throw counterbalanced crankshaft of chrome nickel steel is used. Connecting rods of chrome nickel steel. They are round, of constant section, and hollowed for lightness. They are machined all over. Bearings of bronze, babbit lined with steel retainers. Wrist pins of nickel steel and float in the rods. One cam shaft with two cams operate all the valves. The push rods have ball and socket ends, and are adjustable. Valves are of tungsten steel. Two exhaust valves 1 15/16" in diameter and one intake valve 2 1/8" in diameter to each cyl. Two magnetoes and a 2" Miller carburetors are used. A special type of oil distributor working under a constant pressure of 20 to 40 pounds, and timed with the pistons supplies the engine with the correct amount of oil at all speeds.
