stability augmentation system


Also found in: Acronyms.

stability augmentation system

[stə′bil·əd·ē ȯg·mən′tā·shən ‚sis·təm]
(aerospace engineering)
Automatic control devices which supplement a pilot's manipulation of the aircraft controls and are used to modify inherent aircraft handling qualities. Abbreviated SAS. Also known as stability augmentors.

stability augmentation system (SAS)

i. An autostabilizer system that is essentially a damping device incorporated in most helicopters. The stability augmentation system enhances stability but does not have the ability to hold a given datum.
ii. Various forms of auxiliary subsystems added to the primary flight control to achieve desired aircraft characteristics by selection of variable gain in feedback loops from aircraft control surfaces. These devices often have limited authority and do not move the pilot's controls.
In many aircraft, an inoperative SAS makes the aircraft unairworthy.
References in periodicals archive ?
In the policy statement, the FAA specifically includes "stability and control (such as an autopilot or stability augmentation system)" in the NORSEE equipment category.
A quick check of the panel showed a caution light for the stability augmentation system. I pointed this out to the HAC, and he said that he had released the automatic flight-control system with his cyclic switch, in an effort to troubleshoot our vibrations.