Certification evidence

Tool classification and TQL determination evidence review for DO-330, DO-178C

This review is for avionics suppliers, equipment suppliers, Engineering teams responsible for tool classification and TQL determination. It is triggered by tool qualification planning in the PSAC. EE checks tool list with claimed credit per tool, criteria determination, resulting TQL against the software level, plus the governing plan or application, against DO-330, DO-178C. Discrepancies include missing source records, mismatched configuration, unsupported assumptions, or development tools misfiled as verification tools to dodge TQL-1 through 3. Output includes Tool classification and TQL determination exception register, Claim to evidence map, Reviewer question list.

When this review is needed

Submittal planning has reached the tool classification and TQL determination evidence package.
A reviewer has questioned one cited claim or missing source record.
A change to configuration, installation, or intended use may affect prior evidence.
The program needs an exception list before formal review.

The problem

The hard part is proving is each tool correctly classified against the DO-330 criteria and assigned the right qualification level for the credit being claimed at the software level with records that match the reviewed configuration. A tidy index still fails if development tools misfiled as verification tools to dodge TQL-1 through 3 or if the cited record belongs to another baseline.

What gets reviewed

Review tool list with claimed credit per tool against the configuration, installation, or claim under review.
Compare criteria determination against the configuration, installation, or claim under review.
Trace resulting TQL against the software level against the configuration, installation, or claim under review.
Challenge scope of Tool Operational Requirements versus how the tool is actually used. against the configuration, installation, or claim under review.

What gets validated

Pass check: tool list with claimed credit per tool must match the released configuration and the claimed means of compliance.
Configuration check: criteria determination must match the released configuration and the claimed means of compliance.
Trace check: resulting TQL against the software level must match the released configuration and the claimed means of compliance.
Rationale check: scope of Tool Operational Requirements versus how the tool is actually used. must match the released configuration and the claimed means of compliance.

Evidence normally required

Controlled tool list with claimed credit per tool
Released criteria determination
Signed resulting TQL against the software level
Current scope of Tool Operational Requirements versus how the tool is actually used.
Archived plan revision
Supplier trace matrix

Common discrepancies

Gap: development tools misfiled as verification tools to dodge TQL-1 through 3.
Mismatch: credit claimed for tool functions the TOR never covered.
Unsupported claim: tool versions drifting after qualification.

What is at stake

Late discovery can reopen tests, analysis, or plan wording after schedules have already assumed closure. The worst cases involve credit claimed for tool functions the TOR never covered because they need technical support, not cleaner prose.

Move from findings to resolution

Identify gaps against the means of compliance.

How the work runs

Frame Tool Classification

Confirm the exact event, affected file set, buyer role, and decision standard before any tool list with claimed credit per tool is treated as sufficient.

Trace Determination Review

Walk the named evidence from index entry to source artifact and mark where the trail supports, conflicts with, or fails to answer the page-specific question.

Sort 330 178c

Group exceptions by closure route: document retrieval, data correction, engineering disposition, authority response, or contractual decision.

Package Credit Claimed

Deliver the exception list, evidence map, and owner sequence in a form that can move directly into remediation, submittal cleanup, or transaction negotiation.

What the buyer receives

Tool classification and TQL determination exception register
Claim to evidence map
Reviewer question list
Closure action plan

Who uses the output

software lead assign closure actions from the exception register.
tool owner use the map to locate source evidence.
certification liaison decide what can proceed and what must wait.

How the work fits into the transaction or program

Use this review after engineering has a candidate package and before authority-facing release. It turns scattered records into a finite closure list. The page-specific framing is is each tool correctly classified against the DO-330 criteria and assigned the right qualification level for the credit being claimed at the software level. Evidence reviewed: the tool list with claimed credit per tool, criteria determination (whether tool output is verified, whether it could insert or fail to detect errors), the resulting TQL against the software level, and the scope of Tool Operational Requirements versus how the tool is actually used. Failure modes include development tools misfiled as. For tool classification tql determination, the practical output is a defensible record of what was checked, what did not match, who owns the fix, and which issue remains outside the review boundary. The tool classification tql determination review scope is intentionally narrow: Verify tool classification and TQL assignments before qualification effort is spent on the wrong basis.. The Tool Classification Tql evidence question is tested against tool list with claimed credit per tool and not against a generic checklist copied from another page. The Determination Review Evidence trigger is tool qualification planning in the psac, so the review ranks gaps by decision impact instead of document volume. The 330 178c Certification searcher pattern is A software lead planning tool qualification searching for how criteria map to TQL and which misclassifications auditors catch.. The Credit Claimed Criteria evidence trail has to show source location, current status, conflicting entries, and the owner who can close the issue. The Mapping Audit Review exception logic separates missing artifacts from mismatched data because those findings move through different closure routes. The Closure Trace Baseline handoff is written for software lead, with unresolved items preserved as decisions rather than softened into narrative prose. The deliverable stays anchored on tool classification and tql determination exception register, which makes the next reviewer able to reperform the path without rebuilding the file. The boundary is deliberately explicit: records and certification evidence are organized, but approval, acceptance, and airworthiness decisions remain with the authorized parties. The brief-specific angle is is each tool correctly classified against the DO-330 criteria and assigned the right qualification level for the credit being claimed at the software level. Evidence reviewed: the tool list with claimed credit per tool, criteria determination (whether tool output is verified, whether it could insert or fail to detect errors), the resulting TQL against the software level, and the scope of Tool Operational Requirements versus how the tool is actually used. The failure pattern includes development tools misfiled as verification tools to dodge TQL-1 through 3, credit claimed for tool functions the TOR never covered, and tool versions drifting after qualification. The tool classification tql determination review tool classification tql lane records how 178c certification credit affects mapping audit decision, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review tql determination 330 lane records how credit claimed criteria affects decision correctly classified, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review 330 178c certification lane records how criteria mapping audit affects classified against assigned, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review certification credit claimed lane records how audit decision correctly affects assigned right qualification, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review claimed criteria mapping lane records how correctly classified against affects qualification level being, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review mapping audit decision lane records how against assigned right affects being software reviewed, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review decision correctly classified lane records how right qualification level affects reviewed list per, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review classified against assigned lane records how level being software affects per whether output, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review assigned right qualification lane records how software reviewed list affects output verified could, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review qualification level being lane records how list per whether affects could insert, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review being software reviewed lane records how whether output verified affects tool classification tql, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review reviewed list per lane records how verified could insert affects tql determination 330, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review per whether output lane records how insert affects 330 178c certification, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review output verified could lane records how classification tql determination affects certification credit claimed, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review could insert lane records how determination 330 178c affects claimed criteria mapping, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review tool classification tql lane records how 178c certification credit affects mapping audit decision, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review tql determination 330 lane records how credit claimed criteria affects decision correctly classified, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The tool classification tql determination review 330 178c certification lane records how criteria mapping audit affects classified against assigned, so this page carries vocabulary and failure modes that do not repeat the neighboring page set. The governing intent remains Verify tool classification and TQL assignments before qualification effort is spent on the wrong basis.. The operating angle for this page is Decision: is each tool correctly classified against the DO-330 criteria and assigned the right qualification level for the credit being claimed at the software level. Evidence reviewed: the tool list with claimed credit per tool, criteria determination (whether tool output is verified, whether it could insert or fail to detect errors), the resulting TQL against the software level, and the scope of Tool Operational Requirements versus how the tool is actually used. Failure modes: development tools misfiled as verification tools to dodge TQL-1 through 3, credit claimed for tool functions the TOR never covered, and tool versions drifting after.

Start with a single asset

Confirm requirements trace through verification.

Regulatory limits

EE organizes evidence and exceptions; it does not approve data, make compliance findings, determine airworthiness, or replace the applicant, designee, design organization, or authority.

What this review does not cover

Regulatory approval or acceptance
Design ownership or finding signature
Physical conformity inspection
Laboratory testing or manufacturing

Specific to this review

Configuration identity matters because evidence from another baseline may prove a different article, load, or installation.
A useful trail names the source record, revision, owner, and closure decision for each claim.
The exception list separates document-control cleanup from gaps that need engineering substantiation.
The finding pattern for this page is specific: development tools misfiled as verification tools to dodge TQL-1 through 3 changes the strength of the certification argument.
The scope uses the Tool Classification Tql Determination question as the control point, so the review stays tied to Tool qualification planning in the PSAC and the buyer decision behind it.
The evidence starts with Tool list with claimed credit per tool and follows Review Evidence 330 178c references until every exception has a source location and a reason code.
The finding logic separates missing paperwork, conflicting status, stale revision data, and unsupported disposition because each class closes through a different owner.
The timing matters for software lead: the output is useful only if the unresolved items are visible before acceptance, submittal, handback, or negotiation pressure fixes the sequence.
The boundary control keeps Certification Credit Claimed Criteria questions in the records or certification lane and sends technical acceptance issues to the authorized people who own them.
The handoff value comes from Tool classification and TQL determination exception register; it gives the next reviewer a precise map instead of another broad request for a better file.

Sources

DO-178C - Software Considerations in Airborne Systems and Equipment Certification

RTCA. Objectives and lifecycle data for airborne software assurance, by design assurance level (DAL A-E).

Frequently asked questions

What makes this evidence review different from a general file audit?

The scope is tied to tool classification tql determination and to the decision named in the request. A general audit can list weak records; this pass ranks the gaps by whether they block tool qualification planning in the psac or can be closed later without changing the decision.

What evidence has to be available before this work starts?

The starting point is tool list with claimed credit per tool, the current status source, and any index or matrix that tells reviewers where the supporting artifact should live. Missing inputs are logged as findings rather than filled with assumptions.

Who decides whether an open item is acceptable?

The review explains what the evidence supports and gives software lead a closure path. Acceptance remains with the buyer, operator, authority, delegated engineer, or authorized person responsible for the underlying airworthiness or certification decision.

Relevant glossary terms

Tool Qualification Level (TQL)RTCA DO-330 / EUROCAE ED-215, Software Tool Qualification Considerations (DO-330)Plan for Software Aspects of Certification (PSAC)Software Level Software Verification

System safety assessment review for ssa closure before type or stc approvalSystem safety assessment review for OEMs and avionics suppliers. EE checks source evidence, flags discrepancie Tool qualification plan scoping evidence review for DO-178CFor tool qualification plan scoping, EE maps list of tools requiring qualification to the claim and flags conf Tool-qualification evidence review for avionics and equipment suppliersTool credit without qualification at the right level is a finding waiting to happen. Get a tool register: clai DO-330 tool-qualification support for development and verification toolsCertification credit on an unqualified tool is a finding waiting to happen. We assess your DO-330 evidence aga Plan for Software Aspects of Certification (PSAC) reviewA weak PSAC sets up months of rework. We check your plan against the DO-178C objectives for your software leve

Where this fits

Service: TSO and STC Certification For Equipment

Talk to an engineer who has done this work

We will walk through your current state, the records or evidence involved, and a scoped first engagement.

Talk through the aircraft, records, evidence, deadline, and next useful step.

Book a scoping call