This document, as Output O2.1.2-05 of the GRA – LNC Project, deals with the preliminary definition of the safety requirements for the actuators and the sensors of the Load/Control Alleviation System (LCAS) for the future GRA. The present, second version of the document is issued according to the Technical Annex 1B to the Grant Agreement 2010 of the GRA ITD. The activity has been carried out following the guidelines provided by the documents SAE-ARP 4754 and SAE-ARP 4761, which, as also recommended by the certification standard CS25, represent standard references for the safety assessment of complex airborne systems. Starting from a qualitative evaluation of the consequences related to the loss of the LCAS functions, the system-level safety objectives have been defined according the maximum probability of occurrence that is acceptable for airworthiness certification. The central core of the work has been then dedicated to the derivation of the safety requirements for the LCAS actuators and sensors. This activity has been performed by developing the subsystem-level FTAs for and by allocating the safety budgets on subsystems with a top-down procedure. Different possible solutions in terms of both architectures (i.e. LCAS with dedicated movables or using the primary flight control movables, one or more actuators per movable) and technologies (i.e. electro-mechanical, electro-hydrostatic or piezoelectric actuators, capacitive or piezoelectric accelerometers) have been analysed, in order to provide preliminary indications about system feasibility and expected certification concerns.
Wing Loads Control/Alleviation System Safety Requirements
DI RITO, GIANPIETRO;SCHETTINI, FRANCESCO;
2009-01-01
Abstract
This document, as Output O2.1.2-05 of the GRA – LNC Project, deals with the preliminary definition of the safety requirements for the actuators and the sensors of the Load/Control Alleviation System (LCAS) for the future GRA. The present, second version of the document is issued according to the Technical Annex 1B to the Grant Agreement 2010 of the GRA ITD. The activity has been carried out following the guidelines provided by the documents SAE-ARP 4754 and SAE-ARP 4761, which, as also recommended by the certification standard CS25, represent standard references for the safety assessment of complex airborne systems. Starting from a qualitative evaluation of the consequences related to the loss of the LCAS functions, the system-level safety objectives have been defined according the maximum probability of occurrence that is acceptable for airworthiness certification. The central core of the work has been then dedicated to the derivation of the safety requirements for the LCAS actuators and sensors. This activity has been performed by developing the subsystem-level FTAs for and by allocating the safety budgets on subsystems with a top-down procedure. Different possible solutions in terms of both architectures (i.e. LCAS with dedicated movables or using the primary flight control movables, one or more actuators per movable) and technologies (i.e. electro-mechanical, electro-hydrostatic or piezoelectric actuators, capacitive or piezoelectric accelerometers) have been analysed, in order to provide preliminary indications about system feasibility and expected certification concerns.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
