Cecilia Workshop

Cecilia Workshop is a graphical tool that allows both Fault Trees and MBSA model edition then cuts set and probability computation. Within Cecilia, the MBSA models are based on the formal “AltaRica dataflow” language.
 
The model hereafter has been developed with Cecilia, in parallel with the work done by the working groups Eurocae WG63 and SAE S18 in the frame of the drafting of ED-135A / ARP 4761A guidelines. It illustrates the MBSA model explained in appendix Q9 and represents a way to model a wheel braking system of an aircraft.
 

 
Cecilia export:      DocBook export:      Word/pdf export:      Equivalent Fault Tree:

Note:
– for Cecilia export, unzip the file and import ARP4761_model_[Cecilia_6.n].xml in Cecilia Workshop version 6.0 or later, or in Cecilia reader
– for DocBook export, unzip the file and open ARP4761_model.docbook.xml with your favorite editor
– the Fault Tree has been handmade by another team in order to compare FTA and MBSA approaches
 
“n” iteration:
 
Braking without monitoring
Simulation:    AltaRica export:    “Loss” events list:    “Loss” FFS/MCS at order 1 list:
 
Not Braking without monitoring
Simulation:    AltaRica export:    “Untimely” events list:    “Untimely” FFS/MCS at order 1 list:

 
“n+1” iteration:
 
Braking with monitoring
Simulation:    AltaRica export:    “Loss” events list:    “Loss” FFS at order 2 list:    “Loss” MCS at order 2 list:

 
Not Braking with monitoring
Simulation:    AltaRica export:    “Untimely” events list:    “Untimely” FFS at order 2 list:    “Untimely” MCS at order 2 list: