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What steps are necessary to meet DO-178B compliance?

DO-178B entails five different levels of criticality, ranging from the most critical (Level A) to the least critical (Level E). Each step requires an investment of time and money, and each requires ever-more rigorous documentation of coding and review processes. Companies worry that as they move up the DO-178B criticality chain - and in particular from Level B criticality to Level A criticality - that their costs will rise accordingly. But this is not necessarily true.

First, Levels E and D comprise industry-standard software engineering principles; as such, successfully completing them should involve little to no additional costs for most mature avionics firms. As well, the cost of moving from Level B to A, widely seen as the most expensive of the transitions, may not be as severe as some might think. According to HighRely, a provider of embedded solutions for the avionics industry, the biggest cost driver in this stage is Modified Condition/Decision Coverage (MCDC) testing. However, by using structured COTS, thoroughly training developers, and doing a careful round of testing, the costs can be largely contained.

What regulations need to be met in order to satisfy DO-178B compliance and what are the benefits of using COTS?

Transparency is a pivotal issue in DO-178B compliance and demands that all processes and stages be fully documented in a way that can be easily reviewed and approved by regulators. It's imperative that this process is completed as accurately as possible, but also as efficiently as possible, to avoid delays in certification.

Last minute change requests that invariably have to be made can put previous standards work in jeopardy. More importantly, at each criticality, developers would be responsible for creating and managing their own documentation. Without the benefit of tools or guidelines, regulators will face a difficult review and approval process. COTS solutions can help streamline this process by providing qualifiable code generators, automatic document generation, and other mechanisms in order to reduce effort wherever possible for routine updates or changes. Developers can also take advantage of COTS software tools to support in-house processes. The choice can even be difficult for experienced developers who have been meeting DO-178B regulations for years but still need to find ways to reduce the time required to complete important but mundane tasks, such as performance testing, bug detection, and traceability. Other key considerations include cost, transparency, third-party reliability, and technology's increasing complexity, and COTS is proving itself a viable remedy to these issues.

Furthermore, once a hand-coded application is certified and flying, it can cost a substantial amount to change a line of code due to the recertification process. COTS guarantees a seamless approach to recertification.

Will using third-party software to help reach DO-178B compliance require a larger investment than building the software in-house?

Implementing COTS tools does require an investment, and companies must accurately assess their needs and spend the time necessary to identify the combination of tools that will produce the best solution. Monetarily, the majority of the investment is made up-front instead of in the development stage. But time and again, successful DO-178B compliant companies have shown that this investment pays off in the long run by using DO-178B qualifiable COTS software. Businesses can amortize the investment over several programs, easily reuse designs from project to project, and easily make modifications without having to put in the extra effort otherwise required. In fact, a conservative estimate shows that by using COTS, organizations can slash DO-178B project times by as much as 25 percent, and reduce the costs involved by as much as 70 to 80 percent. To cite one example, Ultra Electronics Datel, a software maker based in the United Kingdom, turned to a COTS tool to reduce the amount of effort required for DO-178B compliance. Using VAPS Qualifiable Code Generator (QCG) software from Presagis, Ultra Electronics Datel reduced the requirements specification and the design and test phases of  avionics display development, resulting in 25 percent faster time-to-market, and 87 percent lower development costs.

What other considerations need to be evaluated before making the choice between in-house development and purchasing COTS software?

By leveraging the latest software techniques, companies - whether they're new to DO-178B or have years of experience - will benefit from fewer coding iterations, which also means less testing for bugs, a notorious problem area when it comes to achieving DO-178B compliance. They will also face less and easier regression testing and improved hardware integration, the latter being an often-overlooked consideration. This is a critical oversight, as DO-178B is designed to help hardware and software operate in harmony.

Companies also need to consider the rapidly evolving sophistication of the avionics industry. Cockpits today are markedly different from their predecessors - the newest commercial aircraft cockpits feature access to live video, high-end menu-based graphics, and a growing dependence on displays in general. An example of a smart display found in modern cockpits is the multi-function display from Barco. This makes it even more imperative for avionics developers to use the right tools to help them certify their systems as quickly and easily as possible. In this way, the effective use of COTS can help them build a stronger competitive advantage.