A fault-tolerant air data/inertial reference unit

A fault-tolerant air data inertial reference unit (ADIRU), a key part of a fault-tolerant air data/inertial reference system (ADIRS), is described. The ADIRS is designed to be the inertial and air data reference for the ARINC 651 Integrated Modular Avionics (IMA) distributed architecture. The ADIRU has been designed to meet the commercial aviation market demands for low life cycle cost and high reliability using simple, reliable methods to provide high-integrity fault detection, fault isolation, and redundancy management. The ADIRU´s internal redundant resources provide quad channel redundancy that is one level higher than conventional triple redundant systems. This allows the ADIRU to provide deferred maintenance capability. Robust partitioning, simple serial internal interfaces, and simple voting planes assure that internal redundant components are properly utilized to provide high-integrity system outputs