Electric Propulsion for Fixed Wing Aircrafts – A Review on Classifications, Designs, and Challenges

With the growing concern of depleting fossil fuel remains and their impact on the environment, there rises an increasing urgency to switch over for alternative sources of fuel in the aviation sector, inducing a rapidly gaining momentum towards more green and clean sources for propulsion. This concern leads to the scrutinization by governmental agencies and corporate players to focus and invest in adopting electric propulsion architecture. A detailed and systematic literature review was conducted according to the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines, to identify all potentially relevant studies using the Springer®, Scopus®, and Web of Science®. Various papers and reviews on the electric cryogenic and non-cryogenic engines were analyzed and selectively reviewed here systematically. This review discusses the field of fixed-wing electric propulsion and analyses several engineering metrics and influencing factors for the same. This review primarily classifies the different available architectures proposed or implemented for electric propulsion. A brief overview is presented to discuss the current implementations of this futuristic technology and also the upcoming prototypes of electric propulsion architectures. The pros and cons of electric propulsion and its influences on aeroplane performance are highlighted. Inferences can be drawn that the electric aircraft design problem forms new networks and bridges between conventional aircraft design disciplines and emerging subsystems to render high fidelity to solve arising issues and prospective goals. For a favourable design of non-conventional aircraft with efficient performance, high specific power (HSP) is required. Non-cryogenic systems are the backbone for several concepts and prototypes on electric aircraft. Hybrid engines enable the pilot to selectively prefer specific means of propulsion according to the phase of the flight being undertaken.