Fault Tolerance Techniques of The Boeing 777 Samuel

Fault Tolerance Techniques of The Boeing 777 Samuel Hishmeh December 6 th, 2006 Fault Tolerance Techniques of the Boeing 777

Background o o Boeing to Develop “Fly-By-Wire” Fly-By-Wire Advantages n n o Safer Cheaper Revolutionized Flight Fault Tolerance Techniques of the Boeing 777

Design Considerations o o Cosmic Rays Hardware Failures “Fly-By-Wire” Functional Separation No Single Fault can Cause Failure Fault Tolerance Techniques of the Boeing 777

Design Philosophy o REDUNDANCY n Triple Modular Redundancy (TMR) o o n Computing System Electrical Power Hydraulic Power Communication Path 4 Modular Redundancy o Actuator Control Electronics Unit (ACE) Fault Tolerance Techniques of the Boeing 777

Flight Control Surfaces Fault Tolerance Techniques of the Boeing 777

Fault Tolerance Techniques of the Boeing 777

Primary Flight Computer Fault Tolerance Techniques of the Boeing 777

ACE Hardware Fault Tolerance Techniques of the Boeing 777

Communication Bus o o o o ARINC 629 Line Replaceable Units (LRU) Triple Modular Redundancy CRC Checking Asynchronous Serial 2 MHz Physical and Electrical Isolation Fault Tolerance Techniques of the Boeing 777

Communication Bus [2] Fault Tolerance Techniques of the Boeing 777

Flight Modes o 3 Modes n n n Direct Secondary Normal Fault Tolerance Techniques of the Boeing 777

Honorable Mentions o o Deferred Maintenance Electrical Isolation CRC Checks Line Replaceable Units (LRU) Fault Tolerance Techniques of the Boeing 777

Questions… Fault Tolerance Techniques of the Boeing 777

References o o Y. Yeh. Triple-triple redundant 777 primary flight computer. In Proceedings of the 1996 IEEE Aerospace Applications Conference, volume 1, pages 293– 307, February 1996. Y. Yeh. SAFETY CRITICAL AVIONICS FOR THE 777 PRIMARY FLIGHT CONTROLS SYSTEM. In Digital Avionics Systems, 2001. DASC. The 20 th Conference, Volume 1, pages 1 C 2/1 -1 C 2/11, October 2001. Fault Tolerance Techniques of the Boeing 777

CRC Diagram Fault Tolerance Techniques of the Boeing 777