Best Selling Books by W. Stone

The purpose of this study was to examine teachers'' perceptions of key elements of the classroom walkthrough and the impact they had upon classroom instructional practices.

The tumbling characteristics of dynamic models of 14 specific airplane designs investigated in the Langley 20-foot free-spinning tunnel for various loadings and configurations are summarized. For three models, tests were made to determine whether recovery from a tumble could be effected by the use of parachutes, and for two of these models, further tests were made to determine the pilot could safely escape from a tumbling airplane. The accelerations that would be acting on the pilot during a tumble were computed for several of the tests.

Metals and plastics as functioning replacements are becoming an important and interesting development in modern surgery. Attempts to substitute chemically inert materials for defective organs or parts of organs were made in early medical history, but only in the past 20 years have these efforts met with any consistent success. It is interesting that eye surgeons were among the first in this field, although the size and delicacy of the usable structures in the eye would seem inconsistent with such work.

The results of an investigation of a specific tail configuration in the Langley 15-foot free-spinning tunnel are presented in order to supplement the existing published data on hinge moments of elevators and rudders in spins. Hinge-moment measurements are presented for a balanced elevator equipped with trim tabs and for a balanced rudder. The empennage was mounted on a fuselage and investigated throughout a range of spinning attitude.