The X-57 program is NASA’s first fully experimental electric aircraft and an early part of the agency’s work to develop sustainable aviation solutions. Instead of petroleum-based jet fuel, it will use commercial, rechargeable lithium-ion batteries to provide the energy needed for flight. The goal is to make flying cleaner, quieter and more sustainable.
To achieve this goal, the X-57 project team repeatedly tested the batteries to ensure they could safely power the aircraft throughout its flight. They also designed a custom lightweight protective case to keep the battery safe.
After the battery was installed, the crew successfully tested the rotation of the X-57 aircraft motor on battery power. Although motors have spun before, in those early days, when developers sat outside the plane and drew power from a test facility or battery.
Before the latest motor rotation test, the aircraft’s cruise motor controller underwent random vibration testing. These hardware acceptance tests are performed on a shaker table, vibrating at the same frequency as the acceleration motor, to ensure that all systems remain stable in flight. The team performed random vibration acceptance testing of all cruise motor controllers on the X-57 aircraft to ensure all systems remained functional while enduring the vibrational environment expected during flight.
The X-57 Maxwell electric aircraft being developed by NASA’s Aeronautical Research Mission Directorate uses fourteen electric motors for a simulated flight, then turns off twelve small electric motors and folds the propellers in flight.
Additionally, the cruise motors are placed on a dynamometer, an electric motor speed tester, to ensure they operate at their planned maximum temperature, power, torque, speed, voltage and current during flight. Once the required integration and system testing is complete, and the aircraft is performing as expected, NASA will conduct taxi and test flight operations.
In the coming months, the X-57 program will begin a series of test flights. Each will expand upon the others and collect data to understand the operation and performance of the aircraft.
The primary goal of the X-57 program is to share the aircraft’s electric propulsion-focused design, airworthiness processes and technologies with industry, standards bodies and regulators, providing a certification method for all-electric propulsion in the emerging electric aircraft market.