Electric vertical takeoff and landing aircraft, or eVTOLs, rely on the same basic motor physics as electric cars, but their engineering priorities diverge sharply. The Joby Aviation powertrain lead, Jon Wagner, explains in this IEEE Spectrum article that aircraft design is driven less by cost and more by weight, redundancy, and system integration.
In automotive systems, efficiency and cost optimization dominate. Manufacturers typically break complex systems into components sourced from specialized suppliers, accepting some inefficiencies at interfaces between parts. In contrast, eVTOL aircraft must minimize mass at every level while maintaining strict safety requirements. This leads to tightly integrated designs where motors, electronics, and structures are developed as a unified system rather than assembled from loosely connected modules.
A defining difference is redundancy. While electric vehicles may include multiple motors for performance reasons, they are not primarily designed with backup systems in mind. Aircraft, however, must continue operating safely even if components fail. As a result, eVTOL propulsion systems incorporate deep redundancy across motors, power electronics, and control systems, adding complexity and cost but ensuring reliability in flight.
Material choices further reflect these priorities. Lightweight, high-performance materials are essential in aviation, even when they significantly increase cost. Every kilogram saved translates directly into improved range, payload, and efficiency. This contrasts with road vehicles, where affordability often outweighs marginal weight reductions.
The broader implication is that eVTOL development is not simply an extension of electric vehicle technology. It represents a distinct engineering domain shaped by safety-critical constraints and performance demands unique to aviation. As companies such as Joby Aviation push toward commercial air mobility, the integration-first approach may prove more important than incremental improvements in individual components.