DO-178C: Definition, Compliance, Tools, and Certification Optimization
Aviation safety has always been of utmost importance. In the past, this was ensured by adhering to strict guidelines and specifications during the development of embedded software systems. DO-178C is one such specification, created with the intention of preventing software bugs from compromising passenger and crew safety. This article will give you a brief overview of DO-178C, its compliance requirements, and some tools that can help you optimize your certification process.
What is DO-178C?
DO-178C is a set of standards and guidelines for the development of commercial aircraft software. It was published by the Radio Technical Commission for Aeronautics (RTCA) in 1992 and has since been updated several times, with the most recent version being DO-178C/ED-12C, released in 2011.
DO-178C is often referred to as the “Software Considerations in Airborne Systems and Equipment Certification” standard. It provides guidance on how to conduct a software development project in order to ensure that the resulting software is safe for use in an aircraft.
DO-178C is not a mandatory standard, but it is widely used in the aviation industry and is required by many aviation authorities, such as the Federal Aviation Administration (FAA) in the United States, when certifying new aircraft.
Overview of DO-178C:
DO-178C classifies safety in five levels, with each level corresponding to the consequence of a software failure:
- Level A (Catastrophic) – A catastrophic failure may cause deaths and usually results in the loss of the airplane.
- Level B (Hazardous) – A hazardous failure has a large negative impact on safety or performance or reduces the ability of the crew to operate the aircraft due to physical distress or a higher workload, or causes serious or fatal injuries among the passengers.
- Level C (Major) – A major failure significantly reduces the safety margin or significantly increases crew workload and it may result in passenger discomfort or even minor injuries.
- Level D (Minor) – A minor failure slightly reduces the safety margin or slightly increases crew workload. Examples of minor failures might include causing passengers inconvenience or a routine flight plan change.
- Level E (No Safety Effect) – This failure has no impact on safety, aircraft operation, or crew workload. An example might include a bug in the in-flight entertainment system.
For each of the five safety levels, a certain number of objectives must be satisfied in order to meet airworthiness requirements and obtain approval for software used in civil aviation products:
| Level | Failure Condition | Objectives | With Independence |
| A | Catastrophic | 71 | 30 |
| B | Hazardous | 69 | 18 |
| C | Major | 62 | 5 |
| D | Minor | 26 | 2 |
| E | No Safety Effect | 0 | 0 |
The phrase “with independence” means that the objective cannot be satisfied unless there is a clearly documented separation of responsibilities.
Since DO-178C became available for sale and use in January 2012, it has become the primary document by which the certification authorities such as FAA (a governmental body of the United States with powers to regulate all aspects of civil aviation), EASA (an agency of the European Union with responsibility for civil aviation safety), and Transport Canada (the department within the Government of Canada responsible for developing regulations, policies and services of road, rail, marine and air transportation in Canada) approve all commercial software-based aerospace systems.
It’s important to note that DO-178C is a non-prescriptive standard, which means that it doesn’t describe what must be done to meet the safety objectives it provides. As such, it gives the developers of software systems used in civilian aircraft a lot of flexibility, but it also sometimes creates ambiguity.
What difference between DO-178B and DO-178C?
DO-178B has been superseded by DO-178C, whose latest version was published in 2012. DO-178C improves upon the DO-178B by using clearer, more concise language and terminology, addressing inconsistencies uncovered from DO-178B Annex A, increasing and clarifying objectives for DAL A, B, and C, and explicitly considering the impact of Parameter Data Item elements on multi-baseline and configuration-dependent software artifacts.
How to support DO-178C?
There are DO-178C tools available from various software development companies which:
- help you create DO-178C artifacts,
- manage DO-178C compliance, and
- perform DO-178C audits.
Using such tools can save you a lot of time and effort in satisfying the DO-178C objectives for your software development project.
DO-178C certification optimization is the process of streamlining your DO-178C compliance activities in order to minimize the cost and effort required to obtain DO-178C certification for your software system.
Certification optimization can be achieved through various means, such as using DO-178C tools, automating DO-178C activities, and improving DO-178C processes.
When used effectively, DO-178C tools can help you automate the creation of DO-178C artifacts, manage DO-178C compliance, and perform DO-178C audits. This can save you a significant amount of time and effort in satisfying the DO-178C objectives for your software development project.
DO-178C compliance doesn’t have to be costly or time-consuming. By using DO-178C tools and automating DO-178C activities, you can streamline your DO-178C compliance efforts and save both time and money.
Visure Requirements ALM Platform:
Providing integral support to the complete requirement process, Visure Requirements is a state-of-the-art requirements management software solution capable of managing all requirement-related information (like requirements, tests, change requests, risks, etc.), their relationships, and their interactions with the users.
Visure Requirements offers comprehensive and agile requirements management for the development and verification of avionic embedded systems, allowing the developers of avionics software systems to standardize and streamline their processes related to DO-178C by providing a single centralized repository for all DO-178C objectives.
Visure Requirements can create, enforce, and manage many-to-many bi-directional traceability links, and it can automatically generate useful traceability matrices and reports to support effective decision-making and ensure the timely completion of all objectives.
These and other qualities make Visure Requirements an indispensable requirements management tool that far exceeds the capabilities of Microsoft Office and Excel, keeping everyone on the same page and ensuring that customers get exactly what they paid for.
Conclusion:
DO-178C is a critical standard for the Aerospace and Defense industry, and Visure has been a leading provider of software solutions to support compliance with this standard for many years. Our platform has been used by some of the largest companies in the world to manage their requirements and ensure safety-critical systems are compliant with DO-178C. If you’re looking for a reliable and proven solution to help you achieve compliance with this important standard, contact us today for a free 30-day trial of our Requirements ALM Platform.
