Abstract: A system for testing space engines at sea level under a very low pressure environment. The system includes a space simulation chamber connected to a diffuser which has two variable area ratio ejectors connected to it in tandem. Each of the ejectors is driven by a jet engine, preferably a turbo jet. The system is capable of providing a low pressure environment of about three or four millimeters of mercury for testing of engines mounted in the space simulation chamber. The system also may be used for other purposes requiring very high vacuum, such as evaporation and dehydration of food products or drugs.

Abstract: a latching device includes a pair of spring projected latch bolts located within a housing and movable outwardly of one end wall thereof for engagement with detents of a pair of doors to be latched in a closed position. A rod extending at one end thereof outwardly of an opposite wall of the housing has a handle at such one end and a transverse bar at an opposite end which engages a pair of lugs provided on the bolts, so that the doors may be unlatched as the handle is pulled from inside the housing so as to move the bar toward the opposite end wall of the housing thereby effecting bolt retraction. A notch is provided on the rod for engagement with a portion of the opposite end wall of the housing for maintaining the bolts in an unlatched position, and bolt guides are provided in the housing in the form of passageways of rectangular cross-section for preventing the bolts, having flat outer surfaces lying parallel to the walls of the passageways, from rotating about their central axes.