Joby Aviation’s Supplier Engineering Strategy: Building a Certified Supply Chain From Scratch

When analysts discuss the challenge of certifying a novel eVTOL aircraft, they typically focus on the aircraft itself — the airframe, the propulsion stack, the flight control architecture. What receives far less attention is the supply chain problem sitting underneath all of it. Joby Aviation is not purchasing from an established catalog of aviation-qualified components for an aircraft type with decades of production history. They are building a supply chain for hardware that, in many cases, has never been manufactured to aviation standards at any scale, let alone production rates.

That distinction matters enormously from an engineering standpoint. The qualification work required to support Joby’s supply chain is not a procurement problem. It is a systems engineering problem, a quality engineering problem, and a regulatory compliance problem — running in parallel, at every supplier, across a novel vehicle program.

The Regulatory Obligation That Flows Downstream

The starting point for understanding Joby’s supplier engineering challenge is understanding what DO-178C, DO-254, and Part 21 production approval actually demand of a prime contractor’s supply chain.

DO-178C (Software Considerations in Airborne Systems and Equipment Certification) and DO-254 (Design Assurance Guidance for Airborne Electronic Hardware) are not product standards. They are process standards. They require that software and complex electronic hardware be developed through a disciplined, documented process — with plans, reviews, traceability artifacts, and independence verification — and that this process assurance extends to every organization that develops covered items, including suppliers.

This means that when Joby procures a motor controller, a battery management system, or any complex electronic assembly that falls under DO-254 scope, the design assurance obligation does not stop at Joby’s front door. The supplier must maintain a Hardware Development Plan, Hardware Verification Plan, and Configuration Management Plan consistent with the applicable DAL. Joby, as the Design Approval Holder applicant, must oversee and accept those plans. The supplier’s development artifacts — requirements capture, hardware design lifecycle data, verification results — become part of the certification evidence package.

The practical consequence is that Joby’s supplier engineering team cannot operate like a traditional aerospace procurement organization that audits to AS9100 and checks First Article Inspection Reports. They are managing supplier development processes, reviewing technical artifacts, and making technical acceptance decisions that directly affect the type certificate. That is a fundamentally different level of engagement.

Part 21 production approval adds another layer. Under 14 CFR Part 21 Subpart G, a Production Approval Holder must establish and maintain a quality system capable of ensuring that each article conforms to its type design. For Joby, this means they must demonstrate to the FAA that every supplier contributing production articles has adequate quality systems, process controls, and nonconformance management — not at some future date, but as a condition of production approval. Supplier quality system adequacy is a certification-critical engineering outcome, not a manufacturing operations detail.

Requirements Communication at the Interface

The highest-risk boundary in any complex system supply chain is the interface between the prime’s systems engineering baseline and the supplier’s development scope. This is where requirements get translated from system-level intent into component-level specifications, and where translation errors do the most damage — because they compound. A requirement that is miscommunicated at the interface propagates through the supplier’s design, verification, and manufacturing processes before anyone has a chance to catch it.

For Joby, this interface carries additional complexity because many of their suppliers are entering aviation for the first time, or entering eVTOL-specific applications for the first time. A motor manufacturer with deep industrial or automotive experience understands motor design. They may have little experience interpreting DO-254 DAL B requirements, understanding what “derived requirements” means in a certification context, or recognizing how their component’s failure modes interact with Joby’s system-level safety assessment.

Effective requirements communication in this environment requires more than a detailed Interface Control Document. It requires a structured supplier engagement program that:

• Translates system-level requirements into component-level allocated requirements with explicit rationale, so suppliers understand not just what is required but why, enabling them to flag conflicts intelligently
• Communicates safety-critical design constraints that arise from Joby’s Functional Hazard Assessment and System Safety Assessment — including failure mode assumptions the safety case depends on
• Establishes clear boundaries between Joby-defined requirements (which the supplier implements) and supplier-designed attributes (which Joby verifies against requirements), preventing scope ambiguity that causes both over-design and under-design
• Provides DO-254 and DO-178C process guidance to suppliers who lack it, including review of plans before development begins rather than audits after the fact

The challenge is that this level of engagement is resource-intensive and requires systems engineers with both domain depth and regulatory fluency. Joby has been building that capability internally, but it is a constraint that shapes the pace at which new suppliers can be brought into the qualification pipeline.

First Article Inspection for Novel Components

First Article Inspection (FAI) in traditional aviation production programs is a mature, well-understood process. AS9102 defines the requirements, suppliers have done it many times, and the primary question is whether a produced part matches the engineering drawing within tolerance.

For Joby, FAI involves a more fundamental question: does the manufacturing process produce the part correctly and repeatably, for a part design that has never been through production before?

This distinction is critical. A novel composite rotor structure, a high-power-density motor wound to tight specifications, or a custom battery module designed around specific cell chemistry — these are not items for which a supplier can point to years of statistical process data demonstrating capability. The first production articles are also, in many cases, the first proof points for whether the manufacturing process is capable of achieving design intent at all.

For such components, FAI must be understood as process validation, not just product inspection. It requires:

Dimensional and geometric verification at the level required by the drawing, using methods appropriate to the feature type — including areas like composite layup thickness and fiber orientation where conventional CMM inspection is insufficient.

Functional performance testing that confirms the delivered article meets all performance requirements, not just dimensional conformance. For a motor controller, this means powered testing under representative loading conditions. For a battery module, this means electrochemical performance verification across the operating envelope.

Material and process certification review, confirming that materials used conform to specifications and that controlled processes (heat treatment, bonding, plating) were performed to documented procedures with traceable records.

Manufacturing process audit, documenting that the production process used for the first article matches the documented manufacturing plan, that operators were qualified, and that in-process inspection points were executed. This creates the baseline process definition that all subsequent production must be held to.

Review of supplier quality records, including nonconformances encountered during first article production, dispositions, and any process deviations — because how a supplier handles nonconformances during FAI predicts how they will handle them in production.

For novel components, the FAI report is also the foundation for determining whether the manufacturing process has been demonstrated capable enough to support the supplier’s Quality Plan for ongoing production. It is not merely a pass/fail gate. It is an engineering data collection event.

Building Supplier Quality Systems for Production Rates

Joby’s near-term objective is certification and initial service entry. But certification under Part 21 requires demonstrating not just that prototype and conforming test articles were built correctly, but that the production system can consistently build conforming articles. The quality system evidence Joby submits to the FAA must address supplier quality adequacy as part of that demonstration.

This creates a forward-looking requirement: Joby must build supplier quality systems now that will be capable of supporting production rates later. The quality infrastructure that supports building ten aircraft is not the same as the infrastructure needed for the production rates that would make Joby commercially viable. Planning for that transition is an engineering activity, not just a manufacturing operations activity.

Key elements of that quality system build-out at the supplier level include:

Control Plans that define inspection methods, frequency, and acceptance criteria for every critical characteristic on every safety-relevant component. These must be developed in coordination with Joby’s systems engineering baseline, because identifying which characteristics are critical requires understanding the safety significance of each parameter.

Statistical Process Control deployment on processes where variability must be understood and managed — particularly for novel manufacturing processes where natural process variation has not yet been characterized.

Supplier corrective action systems capable of root cause analysis at depth, not just symptom containment. Part 21 nonconformance management requires that escapes be fully understood and process changes be validated before return to production.

Configuration management alignment between supplier build records and Joby’s configuration baseline — ensuring that what was built matches what was designed, and that any deviations are formally dispositioned before delivery.

Several of Joby’s suppliers are small or mid-size companies entering aviation quality systems for the first time. Building those systems to Part 21 adequacy, while simultaneously trying to execute development programs, is a genuine organizational challenge. Joby’s supplier development engineering function exists in large part to provide the technical guidance that makes this possible — which is a different model from the arm’s-length supplier relationships that characterize mature aircraft programs.

The Information Management Problem

Running across all of these challenges is a problem that is operational but has deep engineering implications: how does Joby manage the volume and complexity of requirements, design artifacts, verification evidence, and quality records across a distributed supply chain, while maintaining the traceability that certification requires?

Requirements that originate in Joby’s system architecture must be traceable through component-level specifications to supplier design artifacts to verification results to production conformance records. That traceability chain is not just good engineering practice — it is the evidence structure the FAA examines. Any break in the chain creates a certification gap.

Managing this at scale, across suppliers with varying tool environments and varying levels of requirements engineering maturity, is one of the places where the choice of requirements and systems engineering tooling has direct program consequences. Modern tools that support graph-based traceability and structured requirements exchange — rather than document-centric approaches that treat requirements as text in a spreadsheet — offer meaningful advantages when the traceability network spans organizational boundaries. Flow Engineering, for instance, is built around exactly this kind of connected, model-aware requirements management, which makes it relevant to programs like Joby’s where the interface between the prime’s baseline and supplier-developed content is both complex and certification-critical.

Honest Assessment

Joby Aviation’s supply chain engineering challenge is real, substantial, and underappreciated in most public coverage of the eVTOL certification landscape. Certifying a novel aircraft is hard. Simultaneously qualifying a novel supply chain for that aircraft — under process standards that impose obligations on every supplier, for component types with no production precedent — is a compounding challenge that does not get easier as production rates increase.

The engineering sophistication of Joby’s approach, based on publicly available information about their regulatory engagement and certification progress, suggests they understand the problem clearly. Their Part 21 Production Approval efforts and their engagement with FAA on the certification basis for eVTOL-specific components indicate a program that is building the infrastructure for a real production system, not just a certification exercise.

What remains genuinely hard is time and organizational capacity. The supplier development work required to bring novel suppliers to Part 21 quality system adequacy, while simultaneously managing requirements interfaces and FAI programs for novel components, requires engineering resources and schedule that cannot be fully compressed. That constraint is not a Joby-specific failure. It is the honest reality of building a certified aviation supply chain from scratch.

The companies that succeed in eVTOL production will be the ones that treat supply chain qualification as a first-class engineering program — with the same rigor, resourcing, and executive attention as the aircraft itself. By the evidence available, Joby is taking that approach seriously.