A requirement is a singular documented physical or functional need that a particular design, product or process aims to satisfy.
In the PACT context, as well as that of DO-254 and DO-178C, there are system level requirements, high and low-level requirements for software, and requirements and conceptual designs for hardware, all of which define the requirements for the project and its HW/SW sub-components.

Airworthiness Certification Services, LLC., provides resources to facilitate DO-254, DO-178C and other safety-critical programs. Our offering includes documentation templates, review checklists, and a tool called PACT that supports all important aspects of DO-254 and DO-178C compliance during project development. Contact us today for a free quote.

For a complete glossary of DO-254 or DO-178C terminology,  refer to the appropriate document, which can be purchased at