Part 29 certification-basis support for transport rotorcraft navigation equipment

When this review is needed

• A navigation unit is entering a Part 29 submittal and its operational-performance claims have to be tied to the applicable MOPS at the transport level.
• An authority finding questions how the navigation solution behaves when a sensor input degrades on a transport rotorcraft.
• The navigation database update process needs to be shown as controlled to the integrity a transport operation requires.
• The DO-178C software level has to be matched to the more stringent Part 29 failure classification.

The problem

Navigation equipment on a transport rotorcraft answers to operational-performance standards and to Part 29 at once, and the transport basis raises the failure-condition classifications behind the navigation function. The sensor-input handling, the database-currency controls, and the software-level argument usually sit in separate reports that do not state how the equipment meets the performance standard at the level a transport operation needs. When a finding lands on navigation integrity, the team has to build that connection under pressure.

What gets reviewed

• Part 29 paragraphs and the applicable MOPS identified for the navigation function
• How the navigation solution handles each sensor feed in normal and degraded states, traced to evidence
• Database currency and the update-integrity controls behind it weighed against the transport standard
• DO-178C software level matched to the transport rotorcraft failure classification
• The operational credit sought lined up against the evidence that earns it
• Each mapped paragraph and MOPS point recorded as met, partly met, or outstanding

What gets validated

• The applicable MOPS is named and the equipment's performance is shown against it at the transport level
• Degraded-input behavior of the navigation solution is substantiated for the transport failure classification
• Update and integrity controls on the database reach the level the transport operational credit rests on
• The DO-178C level matches the Part 29 failure-condition classification for the navigation function
• The credit being claimed is supported by evidence sized to that credit

Evidence normally required

• The certification basis and issue papers on navigation performance
• The applicable MOPS together with the equipment's declared performance figures
• Specifications for each sensor feed and the degraded-mode analysis
• The database update procedure and the integrity controls that govern it
• DO-178C life-cycle data covering the navigation software

Common discrepancies

• Performance declared against a MOPS the equipment was never formally shown to meet at the transport level
• Degraded-input behavior with substantiation short of the Part 29 classification
• Database integrity controls that do not reach the level the operational credit requires
• A software level below what the transport navigation failure condition demands

What is at stake

A navigation package that cannot show MOPS alignment at the transport level draws findings that question the operational credit sought. If the software level or the database-integrity controls fall short of what the Part 29 classification demands, the equipment can be limited below its intended capability, which defeats the point of the installation on a transport rotorcraft.

How the work runs

What the buyer receives

• A Part 29 standards map tying each paragraph and MOPS point to its evidence and status
• A gap list naming the performance, database, or software evidence still outstanding
• A closure sequence that puts the operational-performance findings ahead of the rest

Who uses the output

• Certification leads answering Part 29 findings on navigation performance
• Engineering leads scoping the database and degraded-mode work still owed
• Compliance managers watching the operational credit against outstanding findings

How the work fits into the transaction or program

The mapping connects the Part 29 basis with the operational-performance standard the navigation equipment is meant to satisfy, at the failure classifications a transport rotorcraft imposes. It runs before the finding response so the operational credit rests on evidence that names the standard and meets the transport level rather than on a general claim of capability.

Jurisdiction-specific considerations

FAA and EASA reference the operational-performance standards for navigation similarly, but the operational credit each grants at the transport level and the way it is documented can differ, so the map flags where a navigation package accepted under one authority needs restated evidence for the other.

Regulatory limits

The mapping shows how the navigation equipment's evidence meets the Part 29 basis and its performance standard, and where it falls short. It does not grant operational credit, issue a compliance finding, or make an airworthiness determination, which remain with the authority.

What this review does not cover

• Flight testing or performance testing of the navigation solution
• Building the database update or integrity control process
• Granting operational credit or issuing any approval

Specific to this review

• On a transport rotorcraft the navigation failure classifications are more stringent, so a software level that passed on a lighter basis can be the finding that limits operational credit.
• Database integrity has to reach the level the transport operational credit depends on, which is a higher bar than a normal-category installation typically carried.
• Degraded-input behavior draws the sharpest scrutiny on a transport rotorcraft, since the navigation solution has to stay safe at a more demanding classification when a sensor drops out.

Sources

Frequently asked questions

Relevant glossary terms

Related pages

Where this fits