Certification, without the guesswork
Whether you need us to hold Design Organisation Approval on your behalf or to reinforce a DOA you already run, we help aerospace programmes to get through certification first time – with a regulatory picture that spans EASA, the FAA and national authorities including the UK CAA.
Certification pathway, whichever position you’re in
Your delegated Design Organisation Approval holder, or we can reinforce your own DOA with specialist capacity and knowledge.
DO-178C and DO-254, done with modern tooling
A seat on the DO-178C/DO-254 standards panel gives us influence and early sight of how the rules are evolving, while purpose-built tool chains replace the old resource-heavy verification peaks.
AS9100-accredited quality management
The baseline that aerospace expects, underpinning every piece of work.
Multi-regulator reach
EASA-certified DOA status, recognised by national authorities including the UK CAA, and FAA engagement through DER relationships.
Built for the certification gap that eVTOL and AAM programmes face
Practical help translating special conditions and acceptable means of compliance into a working certification strategy.
Scope from single-point consultancy to full modification oversight
Engagement sized to what you actually need, not a fixed package.
Your flexible route to certification
Certification is the underestimated gap. Companies rarely expect it to be a bottleneck – until it is. Stirling Dynamics has spent more than three decades inside that process, as an EASA-approved Design Organisation and as a technical partner to companies that hold their own approvals but need the depth or capacity to move faster.
However you’re set up, we can meet you where you are.
Two ways in, one smart outcome
No DOA of your own
Some of the businesses we work with have no Design Organisation Approval of their own. For them, we act as the delegated authority: we hold EASA 21J status, manage the regulatory relationship end to end and carry the compliance demonstration through to sign-off.
Already a DOA holder
Other customers already hold DOA status but lack the internal bandwidth or specific expertise for a given programme. In that case, we work inside their organisation, providing the engineers, the process knowledge and the hands-on delivery they need to hit their own certification objectives, while they retain the regulatory relationship.
It’s less common for two Design Organisations to work together on a DODO basis but it happens occasionally when one DO’s scope doesn’t cover everything a project needs. We’ve run these arrangements successfully on long-term eVTOL programmes where the scope has grown well beyond a single organisation’s original approval.
A regulatory landscape that rarely stays still
Aerospace certification sits across at least three regulatory tiers. EASA governs European airspace and delegates authority to organisations such as ours, with team-based oversight and multiple checks built in. The FAA takes a different approach, delegating to individual Designated Engineering Representatives, while national regulators (including the UK CAA) hold responsibility for aircraft on their own registers. EASA and the FAA are working towards harmonisation, though the philosophical gap between organisation-level and individual-level delegation still shapes how each interprets equivalent evidence.
We hold EASA-approved DOA status (EASA.21J.807), are recognised by national regulators including the UK CAA, and engage with the FAA through DER relationships. That reach means a certification strategy can be built around your actual airspace and customer base – rather than reverse-engineered later when a gap in evidence surfaces.
- EASA
- EASA.21J.807 · DOA
- FAA
- Through DER relationships
- UK CAA
- National regulator
DO-178C and DO-254, done with modern tooling
- DO-178C · software
- DO-254 · airborne electronic hardware
Any aircraft above a certain size – where a systems or software failure could have serious consequences – falls under DO-178C for software and DO-254 for airborne electronic hardware. These standards are applied across civil, military, fixed-wing and rotary programmes. They’re often the reason that companies come to us in the first place, whether they’re searching specifically for DO-178C support or have discovered the requirement partway through a wider development programme.
The old way of meeting these standards meant resourcing verification and validation with 20 or 30 engineers at peak. We’ve invested heavily in integrated tool environments, harmonising up to 15 individual tools into a single working chain: this changes that resourcing picture considerably. We also sit on the DO-178C/DO-254 standards User Group panel, an invitation-only seat that gives us early visibility (and input) into where the standards are heading – not just where they stand today.
Built for where AAM and eVTOL programmes actually are
New entrants to aerospace, particularly in Advanced Air Mobility, face a specific problem: they’re building a company, designing an aircraft and working out a certification strategy all at once –usually with a flying prototype and a certification pathway that doesn’t yet exist in a rulebook.
eVTOL aircraft sit outside the established fixed-wing and helicopter categories. This means blending existing certification specifications with extra conditions written for novel technology – and interpreting acceptable means of compliance that were never written with your configuration in mind.
This is where the gap between a prototype that flies and an aircraft that’s certified tends to be badly underestimated. A prototype flying successfully in controlled conditions is a genuinely different undertaking to demonstrating comprehensive, auditable safety evidence to a regulator.
It’s a point worth being direct about: outside China, no eVTOL anywhere in the world has yet achieved full civil certification. And some of the most visible names in the sector have pushed back certification targets repeatedly despite well-publicised flight testing. But that’s not a reason to be discouraged. It’s a reason to bring in a partner who understands exactly where that gap sits and how to close it.
We’ve supported AAM programmes for over six years, working across product development, certification strategy and compliance demonstration, including long-standing DODO-based support for a major eVTOL manufacturer’s flight test and certification aircraft. We take on companies with incomplete specifications and evolving requirements – at a stage when larger tier-one suppliers typically won’t engage until everything is locked down. That accessibility, combined with the breadth to move from consultancy into design, manufacturing and supply, is a genuinely rare combination in this market.
Why programmes choose us over the alternatives
Startups and emerging AAM programmes typically find themselves stuck between two options, neither of which fits. Large tier-one suppliers want a finished specification before they’ll engage at all, which is a reasonable position for them but an impossible one for a company still iterating on its design. Meanwhile, pure consultancies can supply people and expertise but hand the output back to you to take forward into design, manufacturing and supply – leaving you to stitch together the next stage yourself.
Stirling is different: we’re structured to engage properly with companies whose specifications are still moving, and we stay engaged as those specifications firm up, carrying the relationship from early consultancy through to detailed design, manufacture and supply of the equipment involved. That’s an unusual breadth of expertise to find in one organisation, and it means you’re not re-briefing a new supplier every time a programme moves to the next stage.
It also means we’re not carrying the legacy processes that slow down some of the larger prime contractors. Our tooling, our DOA structure and our engagement model have been built around the pace and uncertainty that new programmes actually run at – rather than adapted from a process designed for mature, stable production aircraft. For a start-up team selecting a certification partner, we offer:
- real engagement at an early stage
- technical depth across DO-178C/DO-254 and DOA authority
- the ability to stay with you into design and supply.
That compelling combination is not something you usually find assembled in one place.
AS9100 Quality Underpins Everything
All our work operates under AS9100, the aerospace-specific extension of ISO 9001. It’s table stakes in this industry and rightly so: it gives you confidence that the process behind our certification and design work is externally audited and held to the standards that aerospace demands, whatever the size or scope of the project.
Scoped to what you actually need
What we don’t do is hold full type certification for entirely new aircraft as a DOA-TC holder; that’s not our position in the market, and we’re upfront about it. What we do cover is everything else: modifications, system upgrades, aircraft conversions and enhancements to existing certified designs – alongside complementary support to other DOAs pursuing type certification of their own. That scope runs from a single piece of specialist consultancy through to full oversight of a major modification programme – sized to the problem in front of you. Not a fixed package.
Bring us your hardest certification question
If you’re weighing up whether you need a delegated authority or expert capacity behind your own approval, that’s exactly the conversation to have with us early. Get in touch, and let’s work out which pathway gets you to a certified aircraft with the least friction.