Last year, NASA announced that it would begin research on six radical new concepts under its Convergent Aeronautics Solutions (CAS) initiative, including solutions for electric propulsion and unmanned aerial vehicles. This year, NASA have added five further research streams to the project, which have the potential to transform aircraft technology if proven feasible.
The main focus remains electric propulsion, with three of the five projects focusing on advancing the technology, beginning with general aviation level. As ever, the main challenge of electric propulsion is battery technology; constructing a battery with enough energy density to power an aircraft. One of these projects, FUELEAP (Fostering Ultra-Efficient Low-Emitting Aviation Power), aims to create a fuel cell system that would use hydrogen found in standard aviation gas and combine it with oxygen pulled from the air to generate electricity. This differs from existing fuel cell technology, which requires storage of hydrogen and oxygen in super-cold liquid form, a system far too complex for use in small aircraft.
Another potential solution to the energy density problem in batteries will be explored through the LION (Lithium Oxygen Batteries for NASA Electric Aircraft) project. This research stream aims to address the issue of electrolyte decomposition, which is the major obstacle in the longevity of lithium ion batteries.
Alongside the challenges posed with energy density in batteries is that of power density in motors (i.e. the amount of power generated compared to the size and mass of the motor). This too is the subject of one of NASA’s new projects, with research being conducted into the possibility of 3D printed components improving the performance of electric motors.
Alongside two other projects aimed at reducing the size and weight of the aircraft tail, whilst retaining safety, and developing lightweight antennas, these feasibility studies will take place over a year or so and it is hoped that the research conducted will result in discoveries that will inform the development of future generations of aircraft technology.