A horological instrument comprising at least two time drums, means rotatably supporting said drums, motor means associated with said drums so that each is rotatably driven and so that one drum controls the rotation of the other drum, said other drum having means associated therewith which divides each revolution thereof into segments of rotation and revolving one segment of rotation for each revolution of said one drum, means constituting an alarm system for said instrument including electrical ...

An ultrasonic sector scanner for producing a sector scan in an object to be examined in which one or more ultrasonic transducers are positioned to direct ultrasonic waves toward the surface of one or more movable reflectors. The movable reflectors traverse an arcuate path with respect to a stationary reflector which is positioned to receive the ultrasonic waves scanning the surface of the stationary reflector from each of the movable reflectors and converge such waves at a point in front of the ...

An improved system for detection and measurement of aircraft wing tip vortices over a wide area. An acoustic echo system with transmitter and receiver spaced from each other in a plane perpendicular to the flight path for illuminating the vortex and picking up scattering of the transmitter signal produced by the vortex, using Doppler frequency spectrum analysis with the maximum and minimum frequencies providing a measure of vortex intensity. A plurality of receivers operating with a common trans...