WHITE PAPER

Aircraft Safety Assessment (ARP 4761)

The aircraft System Safety Assessment (SSA) is a vital foundation for the certification of aircraft and engines along with the
installations of systems and equipment. The role of the safety assessment is to ensure the safety of the aircraft, its crew, and
the occupants. Essentially, aircraft safety is ensured by performing careful analysis, architectural optimization, criticality
level determination, highly reliable components, adequate redundancy of functions and items, adequate monitoring, and
sound maintenance practices.
ConsuNova has the experienced engineers that can perform the SSA and the Designated Engineering Representatives
(DERs) that are authorized by the FAA to approve or recommend approval on their behalf. This whitepaper provides an
overview to understanding the System Safety Assessment process so that you can make informed decisions prior to hiring
experts.
The safety assessment process primarily utilizes the following relevant industry and authority documents, to address the
regulations 23.1309/2510, 25.1309, 27.1309, and 29.1309.

The safety assessment process utilizes experienced engineers (versed in the above documents and regulations) to proceed
through a series of analyses pertaining to the system and aircraft. As the safety assessment proceeds, the following documentation
typically accompanies the various analyses:

• Aircraft Functional Hazard Assessment (FHA)
• Aircraft Fault Tree Analyses (FTAs)
• System FHAs
• System FTAs
• System Failure Modes and Effects Analyses (FMEAs)
• Item FTAs
• Item FMEAs

A common misconception is that the safety assessment goal is to eradicate the potential for hazards; while lofty, such is
impossible with complex asynchronous avionics systems. Instead, potential hazards must be effectively uncovered and
quantified via the philosophy in ths white-paper.