Certification Authorities Software Team

Not to be confused with Commercial Aviation Safety Team.
Certification Authorities Software Team
AbbreviationCAST
Formation1990
ProductsCAST Position Papers
FieldsCertification of airborne software and hardware
No meetings since 2016.

The Certification Authorities Software Team (CAST) is an international group of aviation certification and regulatory authority representatives. The organization of has been a means of coordination among representatives from certification authorities in North and South America, Europe, and Asia, in particular, the FAA and EASA. The focus of the organization has been harmonization[1][2] of Certification Authorities activities in part though clarification and improvement of the guidance provided by DO-178C and DO-254.

Activities

Since 1982, RTCA publication DO-178 has provided guidance on certification aspects of safety-critical software use in civil aircraft. In 1985, the first revision DO-178A was issued. The CAST organization first met November 1990 to develop consistent international certification authority input to the drafting of the next revision, DO-178B, which was released in 1992. In 2003, the organization expanded its scope to address the published certification guidance for airborne electronic hardware provided in the RTCA publication DO-254 released in 2000.[1]

With application of DO-178B, it was discovered that many projects were not complying with DO-178B, but there was also wide variations in how various certification authorities conducted project assessments. In response, the CAST developed a standard software compliance assessment approach. In a manner similar to standard staged engineering design review practices (e.g., 10%-50%-90%-100% Complete), this introduced four standard milestones in a software development project where an FAA authority or representative would assess the applicant's progress towards compliance. A goal was to detect issues in time to for the applicant to make adjustments to maximize successful accomplishment of all certification objectives. The FAA further developed this approach in the "Mega" FAA Order 8110.49 Chapter 2, defining the four Stages of Involvement (SOI) Audits as Planning, Development, Verification (Test), and Final.[3]

From 1998 on, the CAST provided informational recommendations in the form of a series of position papers that were neither policy nor guidance documents.[4] These position papers were among the inputs to the joint RTCA/EUROCAE committee that developed DO-178C, DO-278A, DO-248C, and DO-330, and the technology supplements to these publications (DO-331, DO-332, and DO-333).[1]

The model for international certification authority harmonization has changed since CAST's inception.[5] Certification Management Team Collaboration Strategy now emphasizes direct collaboration with industry on technical topics.[6] CAST has not met since October 2016 and the FAA has removed links to past CAST position papers from its website; Position Papers 1-26 were archived in 2015 [1] and this archive was removed in 2017.[2] All but one remaining position papers were later removed from the website and the link to the remaining CAST-32A will be removed after publication of AC 20-193.[5]

Even though these legacy items have been removed, not all information they contain has been included in replacement publications, so, they remain a source of insight into present guidance.

Position Papers

Series Subject Year
CAST-1 Guidance for Assessing the Software Aspects of Product Service History of Airborne Systems and Equipment 1998
CAST-2 Guidelines for Assessing Software Partitioning/Protection Schemes 2001
CAST-3 Guidelines for Assuring the Software Aspects of Certification When Replacing Obsolete Electronic Parts Used in Airborne Systems and Equipment 1999
CAST-4 Object-Oriented Technology (OOT) in Civil Aviation Projects: Certification Concerns
Status: Cancelled		 2000
CAST-5 Guidelines for Proposing Alternate Means of Compliance to DO-178B 2000
CAST-6 Rationale for Accepting Masking MC/DC in Certification Projects 2001
CAST-7 Open Problem Report (OPR) Management for Certification 2001
CAST-8 Use of the C++ Programming Language 2002
CAST-9 Considerations for Evaluating Safety Engineering Approaches to Software Assurance 2002
CAST-10 What is a "Decision" in Application of Modified Condition/Decision Coverage (MC/DC) and Decision Coverage (DC)? 2002
CAST-11 Criteria for Assuring Complete Software Verification Processes
Status: Superseded by CAST 11A		 2002
CAST-11A Criteria for Assuring Continuous and Complete Software Verification Processes 2007
CAST-12 Guidelines for Approving Source Code to Object Code Traceability 2002
CAST-13 Automatic Code Generation Tools Development Assurance 2002
CAST-14 Use of a Level D Commercial Off-the-Shelf Operating System in Systems with Other Software of Levels C and/or D
Status: Cancelled		 2002
CAST-15 Merging High-Level and Low-Level Requirements 2003
CAST-16 Databus Evaluation Criteria 2003
CAST-17 Structural Coverage of Object Code 2003
CAST-18 Reverse Engineering in Certification Projects 2003
CAST-19 Clarification of Structural Coverage Analyses of Data Coupling and Control Coupling 2004
CAST-20 Addressing Cache in Airborne Systems and Equipment 2003
CAST-21 Compiler-Supplied Libraries 2004
CAST-22 Reuse of Software Tool Qualification Data Across Company Boundaries (Applying the Reusable Software Component Concept to Tools) 2005
CAST-23 Software Part Numbering 2005
CAST-24 Reliance on Development Assurance Alone when Performing a Complex and Full-Time Critical Function 2006
CAST-25 Considerations When Using a Qualifiable Development Environment (QDE) in Certification Projects 2005
CAST-26 Verification Independence 2006
CAST-27 Clarifications on the use of RTCA Document DO-254 and EUROCAE Document ED-80, Design Assurance Guidance for Airborne Electronic Hardware 2006
CAST-28 Frequently Asked Questions (FAQs) on the use of RTCA Document DO-254 and EUROCAE Document ED-80, Design Assurance Guidance for Airborne Electronic Hardware 2006
CAST-29 Use of COTS Graphical Processors (CGP) in Airborne Display Systems 2007
CAST-30 Simple Electronic Hardware and RTCA Document DO-254 and EUROCAE Document ED-80, Design Assurance Guidance for Airborne Electronic Hardware 2007
CAST-31 Technical Clarifications Identified for RTCA DO-254 / EUROCAE ED-80 2012
CAST-32 Multi-core Processors
Status: Superseded by CAST 32A		 2014
CAST-32A Multi-core Processors 2016
CAST-33 Compliance to RTCA DO-254/ EUROCAE ED-80, "Design Assurance Guidance for Airborne Electronic Hardware", for COTS Intellectual Property Used in Programmable Logic Devices and Application Specific Integrated Circuits 2014

References

  1. ^ a b c Leanna Rierson (19 December 2017) [7 January 2013]. Developing Safety-Critical Software: A Practical Guide for Aviation Software and DO-178C Compliance. CRC Press. pp. 52–55. ISBN 9781351834056. Retrieved 2022-03-03.
  2. ^ Cary Spitzer; Uma Ferrell; Thomas Ferrell, eds. (2015). Digital Avionics Handbook, Avionics, Development and Implementation (3rd ed.). Boca Raton, FL: CRC Press. pp. 14–18. ISBN 978-1138076983. CAST was formed to promote harmonization of certification and regulatory positions on software and complex hardware aspects of safety.
  3. ^ Rierson. p. 289-313.
  4. ^ Cary Spitzer; Uma Ferrell; Thomas Ferrell, eds. (2015). Digital Avionics Handbook, Avionics, Development and Implementation (3rd ed.). Boca Raton, FL: CRC Press. pp. 14–18. ISBN 978-1138076983. CAST position papers are for education and information purposes and do not constitute official [FAA] policy or guidance.
  5. ^ a b "Certification Authorities Software Team (CAST)". Federal Aviation Administration. Retrieved 2021-10-29.
  6. ^ "ANAC-EASA-FAA-TCCA Certification Management Team Collaboration Strategy" (PDF). Federal Aviation Administration. 2016. Retrieved 2021-10-29. The CMT should actively engage with industry and promote common solutions and approaches to aircraft certification within the international community.