years before the publication of Penaud's patent Thomas Moy experimented at
the Crystal Palace with a twin-propelled aeroplane, steam driven, which
seems to have failed mainly because the internal combustion engine had not
yet come to give sufficient power for weight.
Moy anchored his machine
to a pole running on a prepared circular track; his engine weighed 80 lbs.
and, developing only three horse-power, gave him a speed of 12 miles an
hour. He himself estimated that the machine would not rise until he could
get a speed of 35 miles an hour, and his estimate was correct.
Two six-bladed propellers
were placed side by side between the two main planes of the machine, which
was supported on a triangular wheeled undercarriage and steered by fairly
conventional tail planes.
Moy realised that he could
not get sufficient power to achieve flight, but he went on experimenting
in various directions, and left much data concerning his experiments which
has not yet been deemed worthy of publication, but which still contains a
mass of information that is of practical utility, embodying as it does a
vast amount of painstaking work.