1
University of the People
Unit 5 Written Assignment
Analyze the report and present a summary, in your own words, of the failures and your comments on them.
A preliminary investigation of flight data showed: nominal behavior of the launcher up to H0 36 seconds; failure of the back-up Inertial Reference System followed immediately by failure of the active Inertial Reference System; swiveling into the extreme position of the nozzles of the two solid boosters and, slightly later, of the Vulcain engine, causing the launcher to veer abruptly; self- destruction of the launcher correctly triggered by rupture of the links between the solid boosters and the core stage. The origin of the failure was thus rapidly narrowed down to the flight control system …show more content…
2.3 The Testing and Qualification Procedures The Flight Control System qualification for
Ariane 5 follows a standard procedure and is performed at the following levels : - Equipment qualification - Software qualification - Stage integration - System validation tests. The review has covered the following areas : - The design of the electrical system, - Embedded on- board software in subsystems other than the Inertial Reference System, - The On-Board Computer and the flight program software. The part of the software which caused the interruption in the inertial system computers is used before launch to align the inertial reference system and, in Ariane 4, also to enable a rapid realignment of the system in case of a late hold in the countdown. During design of the software of the inertial reference system used for Ariane 4 and Ariane 5, a decision was taken that it was not necessary to protect the inertial system computer from being made inoperative by an excessive value of the variable related to the horizontal velocity, a
2
University of the People
Unit 5 Written Assignment protection which was provided for several other variables of the alignment software. The extensive reviews and tests carried out during the Ariane 5 Development Programme did …show more content…
3
University of the People
Unit 5 Written Assignment
More specifically, the following corrective measures will be applied:
to the inertial reference system:
-switch-off or inhibition of the alignment function after liftoff,
-analysis/modification of processing, particularly on detection of a fault (no processor shutdown), -testing to check the coverage of the SRI flight domain;
to the system qualification environment:
-general improvement of representativeness through systematic use of real equipment and components wherever
University of the People
Unit 5 Written Assignment
Analyze the report and present a summary, in your own words, of the failures and your comments on them.
A preliminary investigation of flight data showed: nominal behavior of the launcher up to H0 36 seconds; failure of the back-up Inertial Reference System followed immediately by failure of the active Inertial Reference System; swiveling into the extreme position of the nozzles of the two solid boosters and, slightly later, of the Vulcain engine, causing the launcher to veer abruptly; self- destruction of the launcher correctly triggered by rupture of the links between the solid boosters and the core stage. The origin of the failure was thus rapidly narrowed down to the flight control system …show more content…
2.3 The Testing and Qualification Procedures The Flight Control System qualification for
Ariane 5 follows a standard procedure and is performed at the following levels : - Equipment qualification - Software qualification - Stage integration - System validation tests. The review has covered the following areas : - The design of the electrical system, - Embedded on- board software in subsystems other than the Inertial Reference System, - The On-Board Computer and the flight program software. The part of the software which caused the interruption in the inertial system computers is used before launch to align the inertial reference system and, in Ariane 4, also to enable a rapid realignment of the system in case of a late hold in the countdown. During design of the software of the inertial reference system used for Ariane 4 and Ariane 5, a decision was taken that it was not necessary to protect the inertial system computer from being made inoperative by an excessive value of the variable related to the horizontal velocity, a
2
University of the People
Unit 5 Written Assignment protection which was provided for several other variables of the alignment software. The extensive reviews and tests carried out during the Ariane 5 Development Programme did …show more content…
3
University of the People
Unit 5 Written Assignment
More specifically, the following corrective measures will be applied:
to the inertial reference system:
-switch-off or inhibition of the alignment function after liftoff,
-analysis/modification of processing, particularly on detection of a fault (no processor shutdown), -testing to check the coverage of the SRI flight domain;
to the system qualification environment:
-general improvement of representativeness through systematic use of real equipment and components wherever