(You are here.)
this is your first
visit, please stop by:
the beginning of 1904, the Wrights built a second motor similar to the first, but slightly
larger (214 cu in and 34 pounds heavier) that produced 16 hp (increased to 18 hp as the
cylinders smoothed). Improvements included better cooling, a fuel pump, better oil pump
with pressurized lubrication, and a compression release mechanism to aid starting and
allowing the propellers to free-wheel after shutting off the motor in flight.
to Charles Taylor, "We didn't make any drawings. One of us would sketch out the part
we were talking about on a piece of scrap paper...." Orville Wright's diary of 1904
has the entry, "Took old  engine apart to get measurements for making new
- McFarland, 1953, p 1214-1215.
- Hobbs, 1971, pp 29-33.
- Lippincott, 1987, pp 86-87.
- McFarland, Marvin W. (ed) The papers of Wilbur and Orville Wright. McGraw-Hill
Book Co., New York, 1953, p 1214-1215.
- Hobbs, Leonard S. The Wright Brothers' Engines and Their design. Washington, D.C.:
Smithsonian Institution Press, 1971, pp 29-33.
- Lippincott, Harvey H. Propulsion System of the Wright Brothers. In Wolko, Howard S.
(editor), The Wright Flyer, an Engineering Perspective. The Smithsonian Institution Press,
1987, pp 86-87.
[Submitted by Joe W. McDaniel]
The 1903 engine was restored in 1928 using parts from the 1904, including the
crankshaft and flywheel. The engine you see on the 1903 Flyer 1 that rests in the
Smithsonian is actually a hybrid of both engines.