Certification plan support for an FAA field approval

When this review is needed

• A field-approval effort is starting and the plan needs to scope the work before the data package is built.
• The affected-area analysis was done quickly and may understate what the alteration actually touches.
• The plan commits to a compliance approach that the intended evidence will not fully support.
• An inspector's early expectations differ from what the plan promises and the two need reconciling.

The problem

A certification plan is meant to steer the work, but it is often written to describe an approach the team has already assumed, so it inherits that approach's blind spots. The affected-area analysis is the usual weak point: an alteration that looks local touches a structure, a system, or an interface the plan never lists, and the coverage the plan promises quietly excludes it. When the plan commits to a means of compliance the data package will not contain, the mismatch does not appear until the package is assembled and the promised evidence is not there.

What gets reviewed

• The certification basis stated in the plan checked against the alteration and the aircraft
• The affected-area analysis tested for structures, systems, and interfaces the alteration actually touches
• Each compliance commitment in the plan matched to the evidence the data package will contain
• Review and coordination commitments aligned with what an inspector will expect for this alteration
• DO-160G and ARP4754B activities scoped in the plan where the alteration adds equipment or function
• The plan's promised deliverables reconciled to the package's actual build sequence

What gets validated

• The stated certification basis matches the alteration's scope and the aircraft's configuration
• The affected-area analysis captures every structure, system, and interface the change touches
• No compliance commitment in the plan lacks a path to evidence in the data package
• The plan's review commitments align with the coordination an inspector will require
• Equipment and function additions are reflected in the plan's DO-160G and ARP4754B scope

Evidence normally required

• The draft certification plan and its basis and affected-area sections
• The alteration description, drawings, and installation definition
• The intended evidence set the data package will contain
• The applicable regulations for the aircraft and alteration
• Any early inspector coordination notes on the intended approach

Common discrepancies

• An affected area the alteration touches that the plan's analysis never listed
• A compliance commitment in the plan with no matching evidence in the intended package
• A review commitment that understates the coordination the inspector will expect
• An equipment addition whose DO-160G scope the plan omitted

What is at stake

A plan that understates the affected areas sends the whole effort down a scope that is too narrow, so the missing coverage surfaces late, when it is expensive to add and the schedule has hardened around the original plan. A plan that over-promises its means of compliance is just as costly in reverse: the inspector holds the package to the commitment the plan made, and the modifier has to either produce evidence that was never planned or revise the approach under time pressure.

How the work runs

What the buyer receives

• A gap assessment of the plan's basis, affected areas, and compliance commitments
• An evidence map tying each plan commitment to its intended source in the package
• A closure plan for the promises the data package cannot yet keep

Who uses the output

• Engineering leads scoping the field-approval effort before the package is built
• Compliance staff reconciling plan commitments to the intended evidence set
• Maintenance leadership confirming the affected-area analysis matches the real installation

How the work fits into the transaction or program

The certification plan is written first and everything else is built to it, so an error in the plan propagates into the whole package and the schedule around it. This review runs while the plan still shapes the work, catching an understated affected area or an over-promised means of compliance before the data package is built on the wrong scope and the mismatch surfaces in front of the inspector.

Jurisdiction-specific considerations

For a field approval the plan is coordinated with an FAA inspector rather than a delegated engineering organization, so its commitments have to match what an inspector can review and accept for a one-off alteration. Where the modification is intended to grow into an STC, the review notes where the field-approval plan's scope and commitments would need to expand for the type-certificate path.

Regulatory limits

The review checks that the plan's basis, affected areas, and commitments are deliverable from the package. It does not approve the plan, obtain the field approval, determine airworthiness, or commit an inspector to the approach or scope the plan describes.

What this review does not cover

• Coordinating or obtaining the field approval itself
• Producing the evidence the plan commits to
• Any airworthiness determination on the altered aircraft

Specific to this review

• The affected-area analysis is where a certification plan most often fails, because an alteration that looks local reaches a system or interface the plan never lists.
• A plan that over-promises a means of compliance binds the modifier to evidence that was never planned, since the inspector holds the package to the plan's commitment.
• Because the whole package is built to the plan, a scope error found late costs far more than the same error caught while the plan is still steering the work.

Sources

Frequently asked questions

Relevant glossary terms

Related pages

Where this fits