This Aerospace Information Report (AIR) provides guidance to assess an installed subset of electrified propulsion architectures as defined by AIR8678 against the existing aircraft engine and aircraft airworthiness standards for environmental and foreign object ingestion. This release covers aircraft types, and associated engines, for CS 23 and Part 23 level 1&2, CS VTOL, and FAA Powered Lift (21.17b) both ducted and open rotor. This AIR defines the relative ingestion threats, susceptibilities, and possible system impacts that must be assessed for electrified propulsion systems at the aircraft level. Although these electrified aircraft operate in the same operating environments as existing aircraft, the electrified propulsion system susceptibilities and resulting failure consequences may be unique to electrified propulsion. This document defines the similarities and differences between conventional and electrified propulsion architectures.
Rationale: The electrification of aircraft propulsion is an emerging area which holds much promise for revolutionizing transport aircraft and enabling new mobility options. These technologies have the potential for carbon footprint reduction, noise reduction, improved performance, new aerodynamic efficiencies, and better utilization of energy infrastructure. The application of electric power for aircraft propulsion can take a variety of forms, ranging from partial electric to full electric. The introduction of electric engines to drive propulsors and integration to the aircraft, along with the variety of available methods to generate electricity and store energy offers a great degree of new design freedoms for aircraft and aircraft architectures. The broader degree of the design may require some special considerations when considering electrified propulsion aircraft. The purpose of this document is to evaluate the existing aircraft engine airworthiness standards for environmental and foreign object ingestion sufficiency against the unique system architectures associated with electrified propulsion at the aircraft level.