1. Harris, F.D., Kasper, E.F., Iseler, L.E.: US civil rotorcraft accidents, 1963 through 1997. Technical report, NTRS-NASA Technical Memorandum (December 2000)
2. Mellor, P.H., Yon, J., Williamson, S., Ferman, J., Booker, J.D., Barber, M., Stickels, K., Brison, P.: Electrical machine technologies for an electric tail rotor drive. In: European Rotorcraft Forum (2015)
3. Stickels, K., Brunetti, M., Barber, M., Manimala, B., Brinson, P., Roe, T., Mellor, P.H., Booker, J.D., Williamson, S.J., Yon, J.: Advances in helicopter electric tail rotor drive. In: European Rotorcraft Forum (2017)
4. Kim, H.D., Perry, A.T., Ansell, P.J.: A review of distributed electric propulsion concepts for air vehicle technology. https://doi.org/10.2514/6.2018-4998
5. Datta, A.: Electric-vtol research at University of Maryland—simulation, design, and flight testing. In: Electric and Hybrid Aerospace Technology Symposium (EHATS) (2017)