PL. 45. FRAME OF AERODROME A, JANUARY 31, 1900 [◊]
PL. 46. FRAME OF AERODROME A, JANUARY 31, 1900 [◊]
PL. 47. FRAME OF AERODROME A, FEBRUARY 1, 1900 [◊]
PL. 48. FRAME OF AERODROME A, FEBRUARY 1, 1900 [◊]
[p169]
The “bearing points” were not attached to the frame at the time these photographs were taken, but are seen leaning against the scales in the foreground of Plate [46]. Their position on the frame will be more clearly seen in later photographs, where it will be noted that they were made use of in the more elaborate system of guying which was adopted.
While, in general, the frame at this time seemed to be reasonably stiff and strong, yet it was subjected to a very thorough test by supporting it at different points and suspending from it weights to represent the various parts, such as engine, aviator, wings, rudder and so forth, the deflections which were produced by these weights being carefully noted. It was further tested by subjecting it to vibratory strains, such as it would be likely to meet in actual use. After this the whole frame was tested against torsional strains, such as would be caused by the wind twisting one set of wings more than the other. As a result of these tests it was decided that the frame should be strengthened as far as it was possible to do so without greatly increasing the weight, which even now was found to be rapidly increasing beyond what had been calculated as permissible. The main guy-wires were replaced by heavier and stronger ones, and while these were found to add somewhat to the stiffness of the frame, yet something more seemed necessary to insure safety.