Automatic parachute releases are sensitive to altitude pressure through an altitude blocking mechanism. The principle action to be tested is the consistency of the aneroid in releasing the mechanism at a predetermined altitude.

Normal test procedures involve evacuating air from the test chamber to simulate an increase in altitude above the preset altitude of the release. At this point an arming pin, which is blocking the parachute release firing mechanism, is extracted and the release is armed. Pressurized air is bled back into the test chamber to simulate a rate of decreasing altitude. When the simulated altitude reaches the value for which the parachute release has been set the aneroid releases the firing mechanism and the release operates.

The test chamber also has an adjustable "rate-of-descent" valve to accurately check the FXC Model 12000 rate of descent requirement. It also checks the altitude accuracy of the Model 2100, KAP-3, and Irvin Hitefinder releases.

Completely portable and weighs only 35 lbs.

Completely self-contained.