NASA Bets on a Motor That Won't Quit

UW-Madison engineers prove fault-tolerant electric motors can meet aviation safety standards, clearing a key barrier to certified electric passenger flight

27 Mar 2026

Engineers at the University of Wisconsin-Madison have built and tested a motor drive system designed to keep operating even if part of it fails, addressing one of the most significant technical barriers to certifying electric aircraft for passenger use.

The work, funded by NASA, was led by professors Tom Jahns and Bulent Sarlioglu through the Wisconsin Electric Machines and Power Electronics Consortium. Their 40-kilowatt prototype is built around four isolated inverter-winding modules. If any one fails under the heat, vibration, or power surges of a real flight environment, the remaining three compensate automatically and sustain full motor output.

The principle mirrors the redundancy built into conventional commercial aircraft systems, now being applied to electric propulsion.

The project builds on an earlier NASA-funded 1-megawatt motor drive programme that concluded in 2022, which set records for power density in electrified aircraft propulsion. That work established that lightweight, high-power electric motors could be built at scale. This phase demonstrates they can be made reliable enough to satisfy aviation certification requirements.

A paper summarising the prototype's performance won first prize from the Electric Machines Technical Committee at the IEEE Energy Conversion Congress and Exposition in October 2025, one of the field's most competitive peer review forums.

The nearest commercial application is the emerging eVTOL air taxi market, where several operators are advancing toward US launch across regional routes. The team's stated ambitions reach further. "The objectives that we're setting are really aimed at something more ambitious, for the day when large commercial aircraft will be electrified," said Sarlioglu. "We need to work on addressing the major technical challenges today in order to be ready."

Engineers trained through the programme gain direct laboratory experience with motor drive systems, feeding into the pipeline of technical talent that US electric aviation companies will need as they push toward commercial scale.

Proving fault tolerance at the prototype level is a meaningful step. Whether the same performance holds as systems are scaled up and subjected to full certification testing remains the central question for regulators and manufacturers alike.