The European Union’s pursuit of technological sovereignty in eVTOL (electric vertical take-off and landing) manufacturing, as outlined in its 2023 Strategy for Technological Sovereignty, prioritizes control over critical technologies above cost-effectiveness. Yet, the complexity of modern eVTOL systems reliant on global supply chains for batteries, software, and AI algorithms challenges the notion of what constitutes a “truly European” product.

The airframe and engines may be assembled in Europe, but the intellectual core control software, energy management algorithms, and predictive maintenance systems often originates from American or Chinese platforms. This dependency raises a critical question: how can Europe define and measure technological sovereignty when the most vital components are not under its control?

A new evaluation framework, tentatively termed the “Technological Depth Index” (TDI), is needed to assess not just physical manufacturing but the ownership of decision-making, data management, and development processes.

The illusion of European manufacturing

The EU’s ambition to lead in eVTOL production aligns with its broader goal of reducing reliance on foreign technology, as articulated in the European Commission’s strategic policies. However, the reality of eVTOL manufacturing reveals a paradox. While companies like Airbus and Lilium assemble airframes in Europe, the critical systems driving these vehicles such as batteries from Chinese suppliers like CATL or software platforms from American firms like NVIDIA are rarely European. This creates a superficial sense of sovereignty, where physical production occurs in Europe, but the intellectual property and technological control remain external.

The reliance on global suppliers undermines the EU’s strategic objectives. For instance, energy management algorithms, which optimize battery performance and flight efficiency, are often proprietary to non-European firms. Similarly, AI-driven maintenance prediction systems, which enhance safety and reduce operational costs, frequently run on cloud platforms controlled by American companies like Amazon Web Services or Microsoft Azure.

This dependency not only limits Europe’s strategic autonomy but also raises concerns about data security and long-term competitiveness. A purely geographic definition of “European manufacturing” is insufficient when the technologies defining eVTOL performance are globally sourced.

Analytical note: The disconnect between physical assembly and technological control highlights a gap in traditional industrial metrics, which focus on production location rather than ownership of intellectual property. This gap necessitates a shift toward metrics that prioritize digital and decision-making autonomy.

Defining the Technological Depth Index

To address this challenge, a new framework the Technological Depth Index (TDI) can provide a more nuanced measure of sovereignty. Unlike traditional metrics that track the percentage of components manufactured locally, the TDI would evaluate the degree of European control over three key dimensions: decision-making authority, data sovereignty, and development autonomy. Each dimension requires specific, measurable criteria to ensure objectivity and applicability.

Decision-making authority

Decision-making authority refers to the extent to which European entities control the operational and strategic choices embedded in eVTOL systems. For example, who determines the parameters of the flight control software? If a European manufacturer relies on a U.S.-developed autopilot system, the algorithms dictating flight paths, emergency responses, and energy allocation are shaped by foreign priorities. A TDI metric for decision-making could include:

• Percentage of proprietary algorithms: The proportion of critical software (e.g., flight control, energy management) developed and owned by European entities.
• Integration independence: The ability to integrate components without relying on foreign technical support or proprietary interfaces.
• Update autonomy: The capacity to modify and update software without external approval or access to foreign platforms.

Analytical note: Measuring decision-making authority requires tracing the origin and control of software and AI systems, which are often opaque due to proprietary restrictions. This opacity complicates sovereignty assessments and underscores the need for transparent supply chain documentation.

Data sovereignty

Data sovereignty is critical in eVTOL systems, which generate vast amounts of operational data, from flight performance to maintenance logs. If this data is processed or stored on non-European platforms, it risks being subject to foreign regulations or exploitation. For instance, predictive maintenance algorithms rely on real-time data analytics, often hosted on cloud platforms like Google Cloud. A TDI metric for data sovereignty could include:

• Data residency: The percentage of data stored and processed within EU borders, compliant with the General Data Protection Regulation (GDPR).
• Access control: The extent to which European entities retain exclusive control over data access and usage rights.
• Algorithmic transparency: The ability to audit and understand how data is processed by AI systems, ensuring no hidden dependencies on foreign platforms.

Analytical note: Data sovereignty is not just a technical issue but a geopolitical one. Dependence on foreign cloud providers could expose European eVTOL operators to regulatory vulnerabilities, such as U.S. export controls or Chinese data access laws.

Development autonomy

Development autonomy measures Europe’s capacity to innovate and iterate eVTOL technologies without external constraints. This includes the ability to design new algorithms, improve battery efficiency, or develop next-generation AI systems. A TDI metric for development autonomy could include:

• R&D ownership: The proportion of research and development conducted by European institutions or companies.
• Talent localization: The availability of skilled European engineers and researchers specializing in eVTOL technologies.
• Patent control: The percentage of patents related to critical eVTOL systems held by European entities.

Analytical note: Development autonomy is hindered by Europe’s lag in certain technology sectors, such as semiconductor design and AI algorithm development, where the U.S. and China dominate. Strengthening this dimension requires long-term investment in education and innovation ecosystems.

Challenges in implementation

Implementing the TDI poses significant challenges. First, quantifying intangible assets like decision-making authority or algorithmic transparency is inherently complex. Unlike physical components, which can be traced to a factory, software and AI systems are often licensed or cloud-based, obscuring their origins. Second, global supply chains are deeply integrated, making it difficult to isolate “European” contributions.

For example, a battery manufactured in Europe by a Chinese company like CATL may use European labor but Chinese intellectual property. Third, the lack of standardized metrics for digital sovereignty complicates cross-country comparisons within the EU.

Moreover, the TDI must balance ambition with pragmatism. Completely eliminating reliance on global suppliers is neither feasible nor desirable, given the cost and complexity of duplicating technologies like advanced semiconductors or AI platforms. Instead, the TDI should prioritize strategic areas where Europe can realistically achieve dominance, such as data management or specific software modules.

Analytical note: The TDI’s success depends on its ability to align with existing EU policies, such as the European Chips Act, which aims to bolster semiconductor production. However, without addressing software and AI dependencies, these initiatives risk falling short of true sovereignty.

Opportunities for European leadership

Despite these challenges, the pursuit of technological sovereignty offers opportunities for Europe to redefine its role in the global eVTOL market. By focusing on data sovereignty, Europe can leverage its stringent regulatory framework, such as GDPR, to create a competitive advantage. European eVTOL manufacturers could differentiate themselves by offering systems that guarantee data privacy and security, appealing to privacy-conscious markets.

Additionally, investing in development autonomy could position Europe as a leader in next-generation eVTOL technologies. For example, collaborative initiatives like the European Space Agency’s work on autonomous systems could be adapted for eVTOL applications, fostering innovation in AI and software. Public-private partnerships, such as those between Airbus and European universities, could further strengthen R&D capacity.

Analytical note: Europe’s regulatory and collaborative strengths provide a foundation for sovereignty, but only if paired with targeted investments in critical technologies. Failure to act risks ceding control to global competitors.

A critical perspective

The EU’s focus on technological sovereignty is both necessary and fraught with contradictions. While the rhetoric of autonomy is compelling, the reality of globalized supply chains and technological interdependence cannot be ignored. The notion of a “truly European” eVTOL is appealing but risks becoming a symbolic gesture if critical systems remain under foreign control.

The TDI offers a potential solution, but its implementation requires overcoming significant technical and political hurdles. Without a clear strategy, Europe’s eVTOL ambitions may remain grounded in rhetoric rather than reality.

Analytical note: The tension between sovereignty and globalization reflects a broader challenge in modern manufacturing. Europe must navigate this tension by prioritizing areas of strategic importance while accepting some level of interdependence.

Pragmatic approach

Redefining technological sovereignty in eVTOL manufacturing requires moving beyond traditional metrics of production location to a more sophisticated framework like the Technological Depth Index. By focusing on decision-making authority, data sovereignty, and development autonomy, Europe can better assess its control over critical technologies.

However, implementing such a framework demands transparency, investment, and a willingness to confront the complexities of global supply chains. Only through a balanced and pragmatic approach can Europe achieve true technological sovereignty in the eVTOL sector, ensuring both competitiveness and autonomy in a rapidly evolving industry.

Analytical note: The TDI represents a step toward bridging industrial economics and digital sovereignty, offering a model for other critical technology sectors. Its success will depend on Europe’s ability to align policy, investment, and innovation.