DEPARTMENT OF PHYSICS May 5, 1926
Dr. C. G. Abbot, Assistant Secretary
Dear Dr. Abbot:
This report is an outline of the progress on the rocket work that has been made to date. I am sending vouchers under separate cover.
Test of December 6, 1925
On December 6, 1925, a 12-lb. Rocket in its final form was tested in a frame which permitted an upward lift to the extent of one foot. This model included pumps, and operating and governing devices, as mentioned in the letter to the Institution of October 5, 1925; a double-acting engine, however, being used in place of two separate engine systems, which were tried because they involved less work of construction, but which were found next to impossible to operate together.
This model operated perfectly for 27 seconds, until the liquid propellant were used up, the chamber and nozzle being uniformly, and only moderately, heated, and the rocket being in as good condition after the run as before; the chamber and nozzle being, in fact, the same as used in a number of previous tests, with various governing devices. The lift was just enough to balance the rocket's own weight.