This smaller machine was tested August 8, 1903, the same launching apparatus being employed as with the steam-driven models of 1896. In spite of the fact that one of the mechanics failed to withdraw a certain pin at the moment of launching, and that some breakage of the apparatus consequently occurred, the aeroplane made a good start, and fulfilled the main purpose of the test by maintaining a perfect equilibrium. After moving about three hundred and fifty feet in a straight course it wheeled a quarter-circle to the right, at the same time descending slightly, the engine slowing down. Then it began to rise, moving straight ahead again for three or four hundred feet, the propellers picking up their former rate. Once more the engine slackened, but, before the aeroplane reached the water, seemed to regain its normal speed. For a third time the engine slowed down, and, before it recovered, the aeroplane had touched the water. It had traversed a distance of one thousand feet in twenty-seven seconds. One of the workmen confessed that he had poured into the tank too much gasoline. This had caused an overflow into the intake pipe, which in turn interfered with the action of a valve.
The larger aeroplane with the engineer Manly on board was first tested on October 7 of the same year, but the front guy post caught in the launching car and the machine plunged into the water a few feet from the house-boat. In spite of this discouraging mishap the engineers and others present felt confidence in the aeroplane's power to fly. What would to-day be regarded by an aeronaut as a slight setback seemed at that moment like a tragic failure. The fifty thousand dollars had been exhausted nearly two years previously; Professor Langley had made as full use as seemed to him advisable of the resources put at his disposal by the Smithsonian Institution; the young men of the press, for whom the supposed aberration of a great scientist furnished excellent copy, were virulent in their criticisms. Manly made one more heroic attempt under very unfavorable conditions at the close of a winter's day (December 8, 1903). Again difficulty occurred with the launching gear, the rear wings and rudder being wrecked before the aeroplane was clear of the ways. The experiments were now definitely abandoned, and the inventor was overwhelmed by the sense of failure, and still more by the skepticism with which the public had regarded his endeavors.
In 1905 an account of Langley's aeroplane appeared in the Bulletin of the Italian Aeronautical Society. Two years later this same publication in an article on a new Blériot aeroplane said: "The Blériot IV in the form of a bird ... does not appear to give good results, perhaps on account of the lack of stability, and Blériot, instead of trying some new modification which might remedy such a grave fault, laid it aside and at once began the construction of a new type, No. V, adopting purely and simply the arrangement of the American, Langley, which offers a good stability." In the summer of 1907 Blériot obtained striking results with this machine, the launching problem having been solved in the previous year—the year of Langley's death—by the use of wheels which permitted the aeroplane to get under way by running along the ground under its own driving power. The early flights with No. V were made at a few feet from the ground, and the clever French aviator could affect the direction of the machine by slightly shifting his position, and even had skill to bring it down by simply leaning forward. By the use of the steering apparatus he circled to the right or to the left with the grace of a bird on the wing. When, on July 25, 1909, Blériot crossed the English Channel in his monoplane, all the world knew that man's conquest of the air was a fait accompli.
About three years after Langley's death the Board of Regents of the Smithsonian Institution established the Langley Medal for investigations in aerodromics in its application to aviation. The first award went (1909) to Wilbur and Orville Wright, the second (1913) to Mr. Glenn H. Curtiss and M. Gustave Eiffel. On the occasion of the presentation of the medals of the second award—May 6, 1913—the Langley Memorial Tablet, erected in the main vestibule of the Smithsonian building, was unveiled by the scientist's old friend, Dr. John A. Brashear. In the words of the present Secretary of the Institution, the tablet represents Mr. Langley seated on a terrace where he has a clear view of the heavens, and, in a meditative mood, is observing the flight of birds, while in his mind he sees his aerodrome soaring above them.
The lettering of the tablet is as follows:—
SAMUEL PIERPONT LANGLEY
1834-1906
SECRETARY OF THE SMITHSONIAN INSTITUTION
1887-1906
DISCOVERED THE RELATIONS OF SPEED
AND ANGLE OF INCLINATION TO THE
LIFTING POWER OF SURFACES WHEN
MOVING IN AIR