FCAS

FCAS may refer to:


 * Familial cold autoinflammatory syndrome, a genetic disease
 * Fellow of the Casualty Actuarial Society, a U.S. professional society
 * Frequency Control Ancillary Services for electric power grids
 * Future Combat Air System, a sixth-generation fighter jet currently in development by France, Germany, and Spain
 * Future Combat Air System (UK), a sixth-generation fighter jet, the BAE Systems Tempest, and related technologies currently under development by the United Kingdom, Italy and Sweden.
 * FCA Serbia