NIAR conducts 50-ft eVTOL battery drop test

Wichita State University's National Institute for Aviation Research (NIAR) conducted its first successful full-scale 50-foot Electric Vertical Takeoff and Landing (eVTOL) battery drop test at the Jerry Moran Center for Advanced Virtual Engineering and Testing (AVET).

The test, a collaborative effort between NIAR AVET and BETA Technologies, was sponsored by the Federal Aviation Administration. It is part of an ongoing research program on the Integrated Crashworthiness Safety approach of future eVTOL aircraft.

Occupant safety is an integral part of the overall technical and management processes associated with the design, development, and operation of eVTOL transport systems. To guarantee occupant safety, it is necessary to evaluate and analyse the performance and behavior of the complete vehicle (seats, batteries, and the surrounding composite airframe structure) during an emergency landing event (structural, thermal, and electrical).

NIAR will evaluate the crashworthiness performance of eVTOL battery packs and their surrounding structure during a free fall of 50 feet based on 14 CFR § 27.952 and EASA MoC SC-VTOL 2. According to these guidelines, the following conditions must exist.

Fuel cells and fuel tanks require drop tests to validate crashworthiness. Due to the prevalence of fuel tanks and the novelty of battery systems in aircraft, EASA has adopted these fuel tank drop test requirements for use with battery systems as a starting point. The FAA is also pursuing this path while simultaneously researching methods that are more permanent.

Drop testing of fuel systems requires a 50-foot drop of a nearly filled fuel system onto a flat, non-deforming surface. After the drop, the fuel system undergoes monitoring for leakage or fire. Similarly, a battery system should be critically charged and dropped from at least 50 feet, then monitored for leakage of gas or fluids, as well as fire or explosion.

This test program and simulation studies will provide information regarding the items relevant to FAA and industry including:

Structural performance of the battery and evaluation of load transfer into the cabin and eVTOL composite airframe structure.

Thermal performance of the battery and risk of thermal runaway/explosion. Is thermal shielding required, and will current composite and advanced materials used for the construction of the fuselage be acceptable for this use?

Electrical performance of the battery and risk of high-voltage discharge to the surrounding eVTOL structure, occupants, or first response personnel. Can composite materials used for the construction of the cabin floor provide shielding during emergency landing situations?

Generate battery drop test experimental data from different representative eVTOL battery architectures for the FAA in order to define future test requirements and MoC.

The NIAR team would like to acknowledge the efforts of the following organisations and individuals fundamental to this program.

BETA Aircraft for providing the test article and engineering support for the eVTOL battery pack.

The FAA including Dr. Joseph Pellettiere, Chief Scientific and Technical Advisor of Crash Dynamics and David Stanley, research engineer, for sponsoring this research program.

The fourteen NIAR AVET Laboratory staff and students led by Dr. Robert Huculak, Luis Gomez and Marcus Pyles

Sedgwick County Fire District #1 Deputy Chief of Operations Carl Cox; Division Chief of Community Risk Reduction Robert C. Timmons, and their crew for helping us keep a safe environment for the test.