AT approximately half past ten o’clock on the morning of Dec. 17, 1903, Orville Wright piloted the famous Wright powered Wright biplane a distance of a little over 120 ft. in 12 sec., at a maximum altitude of 10 ft. and at a speed of slightly over 31 m.p.h. That flight which has gone down in history as man’s first successful attempt to stay aloft in a heavier-than-air craft was one of four flights made that historic morning at Kitty Hawk, N. C., the longest of which was made by the late Wilbur Wright for a distance of 852 ft. in 59 sec.

BROADLY speaking, design of aircraft covers aerodynamics and structural considerations, but still more broadly it involves power plant and equipment, for these latter have had an important bearing on advances in design. Prior to the first successful flight of a power driven man carrying plane, Lillenthal, Chanute, the Wright Brothers and Montgomery had made some progress with glider experiments.

THE development of the aviation engine from a “delicate” piece of mechanism weighing 10 lb. per hp. to the “robust” mechanism weighing only 1½ lb. per hp. is noteworthy mainly by the absence of any radical change in either form or operation.