STANAG 4671
STANAG 4671 compliance software
Unmanned aircraft system manufacturers seeking a military type certificate against the USAR airworthiness requirements.
STANAG 4671 sets the airworthiness requirements for military unmanned aircraft. ComplyTrain ships the USAR requirement tree and certification document set, so the compliance matrix an assessor asks for is the system's normal output.
ComplyTrain fully supports this standard
What STANAG 4671 is
STANAG 4671, through the USAR airworthiness requirements, is the basis on which a military unmanned aircraft system is type certified. It is structured in subparts in the way civil airworthiness codes are, covering general and certification basis matters, flight, structures, design and construction, powerplant, equipment and systems, operating limitations and the flight manual, continued airworthiness, and the control station and human factors.
Of the 20 requirements in the tree, 17 are critical. That ratio is the highest of the NATO standards ComplyTrain supports, and it reflects what the standard is for: this is the one where the consequence of an unevidenced claim is not a finding but an aircraft.
The compliance matrix is the deliverable
Underneath the engineering, certification is an evidence exercise with a specific shape. An assessor expects a compliance matrix: each applicable requirement, the means of compliance chosen for it, and the evidence produced by that means. Analysis, test, inspection and similarity are all legitimate means, and the matrix is where the choice is declared and defended.
This is the clearest possible fit for a requirements system, because the compliance matrix is not a document somebody writes at the end. It is a view of the work as it stands, and it should be true on any given day rather than assembled for a review.
The safety assessment chain
System safety runs as a chain rather than a single document: a functional hazard assessment at aircraft level, a preliminary system safety assessment for each subsystem, and a system safety assessment demonstrating compliance. Failure conditions are classified by severity, quantitative probability analysis is checked against defined thresholds, and catastrophic failure conditions are accounted for cumulatively rather than one at a time.
Continued airworthiness does not end at certification
The instructions for continued airworthiness carry a segregated airworthiness limitations section, mandatory replacement times and inspection intervals, and a scheduled review of the design usage spectrum. A type certificate is a beginning, and the obligations that follow it are part of the standard rather than an afterthought.
How ComplyTrain helps you meet it
The USAR requirement tree and the certification document set are prebuilt and ship with the standard. This is the deepest document set of the NATO standards ComplyTrain supports, and the one where certification language is fully at home, because there is a real type certification basis to build toward.
- The USAR requirement tree by subpart, with criticality, and the means of compliance recorded against each requirement - Requirements Management
- A type certification basis document and a UAS type design specification - Document Control
- An airworthiness and safety policy - Document Control
- Procedures for system safety assessment, structural substantiation, command and control data link design and verification, and the flight test programme - Document Control
- Instructions for continued airworthiness, with the airworthiness limitations kept segregated - Document Control
- A compliance verification procedure and a USAR compliance review checklist - Document Control
- Safety risk assessed and tracked as a live framework rather than a static document - Risk Management
Because the means of compliance is recorded against the requirement, and evidence is attached to it, the compliance matrix is a report rather than a project. Gap analysis over the tree answers the question that matters during certification: what is still unevidenced, and how was it meant to be shown?
ComplyTrain is not a certification authority, holds no airworthiness approval and does not grant type certificates. It is the system in which you build and evidence your case, which is then assessed by the authority.
Questions
Does ComplyTrain certify our aircraft?
No, and no software can. Type certification is granted by an airworthiness authority against your certification basis. ComplyTrain holds the requirements, the declared means of compliance and the evidence behind them, so the case you present is complete and traceable. The assessment remains the authority's.
What exactly is a compliance matrix?
A record of each applicable requirement, the means of compliance chosen for it, and the evidence that means produced. It is what an assessor reviews to see whether the case is complete. Because ComplyTrain records the means against the requirement and attaches evidence to it, the matrix is a view of current state rather than a document assembled before a review.
How is the system safety assessment handled?
As a connected chain rather than a set of separate documents: a functional hazard assessment at aircraft level, preliminary system safety assessments per subsystem, and a system safety assessment demonstrating compliance, each linked to the requirements it discharges. Failure condition severity classifications and probability analyses are held against the requirement, including the cumulative treatment of catastrophic conditions.
Does this cover the control station and the crew, or only the aircraft?
Both. The standard covers the control station and human factors, including handover of control between stations, demonstrating positive control through a handover, transition timing, and whether displays and controls prevent confusion when more than one aircraft is being handled. Minimum crew determination accounts for that workload.
What happens after the type certificate?
The continued airworthiness obligations begin. The instructions for continued airworthiness must be complete, with a segregated airworthiness limitations section, specified mandatory replacement times and inspection intervals, and an established schedule for reviewing the design usage spectrum. These are requirements of the standard rather than good practice after it.
How much is prebuilt, and can we start on our own?
The requirement tree and all ten document templates ship approved and mapped, the deepest set of the NATO standards we support. You supply the certification basis, your engineering content and your evidence. Provisioning is done by our team, so the first step is a conversation rather than a signup.
The process
Building a certification case that holds together
Type certification is an argument supported by evidence. These four steps are what keep the argument answerable at any point rather than only at the end.
Establish the certification basis
Record the applicable requirements, any special conditions, the design usage spectrum and the aircraft classification. The certification basis is the agreement everything downstream is judged against, so it is a controlled document from the start.
Declare a means of compliance for each requirement
Analysis, test, inspection or similarity: each applicable requirement gets a chosen means, recorded with it. This is what turns a requirement list into a compliance matrix an assessor can read.
Build the safety assessment chain
Functional hazard assessment, preliminary system safety assessments and the system safety assessment connect to the requirements they discharge, with failure condition classifications and probability analysis held against them rather than filed separately.
Carry it into continued airworthiness
The instructions for continued airworthiness, the segregated airworthiness limitations, replacement times and inspection intervals, and the design usage spectrum review are part of the certification, not a sequel to it.