Director Powertrain Engineer Jobs in California (NOW HIRING)

About Zipline

Zipline is the world's largest and most experienced drone delivery service. We are on a mission to serve all humans equally by ensuring access to food, medicine and essential goods anytime, anywhere. We design, build, and operate the world's largest autonomous logistics system, delivering critical supplies quickly and reliably. Today, Zipline operates on four continents, makes a delivery somewhere in the world every 30 seconds, and has completed millions of deliveries to date, including blood, vaccines, medical supplies, food, and retail products.

Our customers include the world's largest and most prominent healthcare systems, governments, retailers, restaurants and global businesses who rely on us to save lives, reduce emissions, increase economic opportunity, and provide delivery from point A to point B as fast as possible. The drone is only 15% of what we've built to enable seamless, reliable, global operations.

Our system strengthens supply chains, reduces congestion, and gives people time back. With more than 140 million commercial autonomous miles safely flown, Zipline is redefining access to healthcare, consumer products, and food across the globe.

We operate at a global scale and are looking for practical problem solvers who thrive on real‑world challenges and rapid growth. Our team is motivated by building systems that have a direct, meaningful impact on people's lives and by scaling the future of logistics. We are seeking people who sculpt from first principles, enjoy facing adversity, and can do the impossible at record breaking speeds.

About You and The Role

Zipline's aircraft rely on electric propulsion and actuation hardware that performs predictably in demanding conditions. As a Senior Motor Test Engineer, you will build the evidence behind that confidence by characterizing motors, propulsion systems, actuators, and propeller subassemblies in the lab and connecting results to flight and field performance.

You will own performance and reliability test campaigns from specification through technical recommendation. Your work will inform design release, vehicle readiness, field reliability, model validation, and production‑test decisions.

What You'll Do

• Conduct full electromechanical characterization of BLDC motors including loss characterization, thermal coefficient extraction, and demagnetization testing
• Evaluate propulsion systems (motor + inverter + propeller) for thrust, efficiency, and thermal behavior across the full operational envelope
• Test servo and motor‑based actuators for positional accuracy, losses, holding torque, and closed‑loop dynamic response
• Define and own test specifications covering efficiency maps, thermal performance, torque‑speed curves, cogging, back‑EMF, and endurance
• Perform root cause analysis on field failures and correlate back to test data to close the loop between lab and flight
• Own the full performance and reliability test campaign for your hardware – you are the go‑to person to understand how a part will perform in the field, and when the hardware is pushed to its limits.
• Characterize wear‑out mechanisms for complex actuator and propeller subassemblies, subject to billions of damage cycles per lifetime.
• Develop novel ways for validating motor and structural models and FEA validation.
• Partner with mechanical, electrical, and firmware engineers to translate design intent into rigorous test requirements
• Work with manufacturing to develop production test strategies that balance coverage, throughput, and cost
• Develop automated test scripts and data acquisition pipelines (Python, or equivalent)

What You'll Bring

• Hands‑on experience with electric motors and actuators, including efficiency characterization, losses evaluation, testing to evaluate electrical and thermal models.
• Hands‑on experience with actuator performance and control system evaluation.
• Hands‑on experience with structural and dynamics performance, including material testing, dynamic response, accelerometer and strain instrumentation.
• Experience building or improving test fixtures, dynamometers, thrust stands, instrumentation, or automated data‑acquisition systems.
• Proficiency in Python or equivalent.
• Sound engineering judgment to connect test results to design decisions, model validation, reliability risks, and field performance.
• Experience working across hardware design and manufacturing teams to translate test evidence into practical product and production changes.

What Else You Need To Know

Zipline is an equal opportunity employer and prohibits discrimination and harassment of any type without regard to race, color, religion, age, sex, national origin, disability status, genetics, protected veteran status, sexual orientation, gender identity or expression, or any other characteristic protected by federal, state or local laws or our own sensibilities.

We value diversity at Zipline and welcome applications from those who are traditionally underrepresented in te