The Wright motor for the job - WAS: 13 horsepower

Veedub:

Usually I defer to your great wealth of knowledge about all things
that fly. But in this case, I feel the need to point out a few
corrections to your statements about the 1903 Wright motor, per my
last reading of "The Papers of Wilbur & Orville Wright" (complied from
letters and field notes) by M. McFarland, c.1953, and the 2003 tests
of a reproduction engine built by The Wright Experience:

The 1903 Wright engine developed approx 11.8 hp on startup, which
dropped to approx. 8.3 hp at takeoff, and perhaps less by the end of
the 59 second "4th flight" of 12/17/1903.

The two propellers were 8.5" dia. and turned at 330-350 rpm, with the
ENGINE turning about 1250 rpm. By my math, that's a 3.57:1 reduction.

I the wing area of the 1903 was 510 sq. ft not counting 48 sq. ft for
the biplane canard elevator.

Orville reported the speed of the flyer through the air as 31 mph.
This was based on the measurements from the Richard anamometer and was
calculated. However, it is believed that the Richard anamometer may
have been recording about 10% low. (This is speculation - both
historic and modern and has not been tested one way or the other.)

The flyer was launched into a headwind of 21-24 mph, giving the
machine a ground speed of 6-7mph.

Having said that, I welcome any corrections that are more accurate, if
they can be documented. (I'm also working from memory, so I can
provide better references at a later date.) I am curious to know where
the information regarding modification to the engine comes from. The
original block #1 was destroyed in the blow-over of 12/17/1903 and is
now on display at Kitty Hawk (minus the cylinder that was cracked
off.) Wilbur and Charlie had 3 blocks cast in 1903 and at least one of
them was used in 1904. (This is part of the engine currently on the
machine in the Smithsonian, although the 1903 crankshaft disappeared
after an exhibition I believe in 1908, so that part isn't original
either.) The 1905 machine used the last block. Its currently on
display at Carillon Park in Dayton. (Just checked the photos, but
didn't see any sparkplugs, only the make/break points. Maybe you are
refering (sp?) to the later Wright vertical 4 and 6 cylinder engines
used in 1908-1912? If anyone has Howard DuFor's book about Charlie
Taylor, it's probably the best source. Howard is the de-facto expert
on Wright engines.

Several Wright 1903 reproduction and replica aircraft have been
powered by air-cooled "lawn tractor" engines. A buddy of mine from
Georgia used an 18hp Kholer flat twin with an intermediate belt re-
drive setup that powered the chain-redrive from the original plane.
Wright Redux used something similar for a test-flight. They can be
made to work with this aircraft.

I had on several occasions considered adding simple landing gear and
"power struts" to my glider. These would be a composed of a 31cc
Royobi weedwhacker engines driving a 14-16" model airplane props and
would be fitted in place of the 6 rear struts on my glider. Since I
never made it to the planned flight testing session in Nag's Head in
2002, I never proceeded with this plan.

In 1907, Ben Epps (of the Epps aviation clan) reportedly flew a
monoplane powered by a 15 hp Anzani v-twin.

Food for thought and research.

Harry Frey
Wright Brothers Enterprises