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The purpose of this paper is to analyze the electric propulsion use in civil aviation and propose a framework for certification of electric propulsion subsystems. Although electric propulsion architectures are discussed as key technology for the future of aviation, the industry standards as well as regulations fail to cover the application in full extent, specifically for commercial large airplanes. This paper proposes an approach for the analyses of reliability and certification of the new-generation propulsion system by pointing out the “common structure” among the possible architectures.

The research process used in this paper consists of following steps: the challenges of the hybrid-electric propulsion is listed, the architectures of the hybrid-electric applications in the literature are identified, the differences of the hybrid architectures from the present applications by means of application and standardization are discovered, the architectures are analyzed and the two main subsystems are defined – the present combustion system and the common unit, which is a similar structure used in all-electric aircraft. For this purpose, the standards used for design basis and certification of the present propulsion system and their relationship with the subsystems of the architectures have been analyzed. The procedure for the reliability assessment of the system is given, a framework for the safety assessment and the certification of the propulsion systems is proposed to make it easier and without sacrificing the already accumulated experience. This study shows that by using the common unit, the present certification framework can be used, by focusing on the reliability of the common unit and its integration with the rest of the architecture.

A specific definition of common unit is proposed, to point out the difference in certification efforts of hybrid-electric propulsion architectures. Yet, there is no data available for propulsion-level airborne battery and electrical systems to assess the reliability. Thus, dividing the propulsion system into two main systems and providing a model for certification of the common unit sub-system would be beneficial for easy deployment of the hybrid architectures both for design and for certification. In this paper, it is proposed that by using this common unit, the present certification framework can be used as it is, by focusing on the reliability of the common unit and its integration with the rest of the architecture.

The aircraft certification regulations act in two ways: they provide a starting point for new design projects, and they are a basis for certification of the final system. This study aims to draw focus on certification issues on the new-generation hybrid-electric propulsion systems. With the introduction of hybrid-electric propulsion for large aircraft, the present standards (CS-25, CS-E, CS-P, CS-Battery and CS-APU) create an obstacle for further progress as their borders get into each other. Instead of developing a new set of standard(s), this paper proposes a new approach by dividing the propulsion system into two subsystems.

This research proposes a definition of “common unit” for simplification of the hybrid-electric propulsion architectures for large civil aircraft. The common unit consists of both battery and electrical components and their reliability shall be considered for hybrid-electric propulsion.

The Annual Conference held in London and sponsored by British Caledonian Airways attracted delegates from 18 countries covered many aspects of airworthiness.

Bird strike and hail impact resistances are considered in relation to the fulfilment of airworthiness/crashworthiness regulations as specified by appropriate aviation authorities. Before aircraft are allowed to go into service, these regulations must be fulfilled. This includes the adaption of the wing leading edge (LE) structure to smart diagnostics and an easy repair. This paper aims to focus on the wing LE, although all forward-facing aircraft components are exposed to the impact of foreign object during the flight. The best practices based on credible simulations which may be appropriate means of establishing compliance with European Aviation safety Agency and Federal Aviation Administration regulations regarding bird strikes, together with the problem of collisions with hailstones, are overviewed in aspect of accuracy and computing cost.

The best means of evaluating worldwide certification standards so as to be more efficient for all stakeholders by reducing risk and costs (time and money consuming) of certification process are recommended. The very expensive physical tests may be replaced by adequate and credible computer simulations. The adequate credible simulation must be verified and validated. The statistical approaches for modelling the uncertainty are presented in aspect of computing cost.

The simulation models have simplifications and assumptions that generate an uncertainty. The uncertainty must be identified in benchmarking tests. Instead of using “in house” physical tests, there are scientific papers available in open literature thanks to the new trend in worldwide publication of the research results. These large databases can be efficiently transform into useful benchmark thanks to data mining and knowledge discovery methods and big data analyses. The physical test data are obtained from tests on the ground-based demonstrator by using high-speed cameras and a structural health monitoring system, and therefore, they should be applied at an early stage of the design process.

The sources of uncertainty in simulation models are expressed, and the way to their assessment is presented based on statistical approaches. A brief review of the current research shows that it widely uses efficient numerical analysis and computer simulations and is based on finite element methods, mesh structure as well as mesh free particle models. These methods and models are useful to analyse airworthiness requirements for damage tolerance regarding bird-strike and hail impact and haves been subjected to critical review in this paper. Many original papers were considered in this analysis, and some of them have been critically reviewed and commented upon.

IT is a particular pleasure to remark on the first flight of Concorde 001 at Toulouse on 2nd March, 1969 and the first flight of Concorde 002 at Filton on 9th April, 1969. The first steps of the extensive flight test programme have begun in earnest. I should like to offer to the constructors of this aircraft and its engines the congratulations of my Board on their achievement.

Not to be missed at the 1983 Paris Show was the Shuttle Orbiter ‘Enterprise’ mounted on a modified Boeing 747 carrier aircraft. This combination visited Paris as part of a tour on both sides of the Atlantic which demonstrated to a wide public the only practical way to ferry an orbiter and also showed the method by which approach and landing tests had been conducted at the beginning of the Shuttle programme.

The purpose of this paper is to discuss European Aviation Safety Agency’s (EASA’s) Prototype Regulation on Unmanned Aircraft Operation and introduce the tool Operational Risk Considerations for Unmanned Aircraft Systems (O.R.C.U.S.). In contrast to existing airworthiness regulations for civil manned aircraft, EASA’s approach is focussed on flight operations and not aircraft, a significant change for the domain of civil airworthiness.

O.R.C.U.S. is a software risk analysis tool developed by the corresponding author. It encompasses all relevant factors for flight operations of light Unmanned Aircraft Systems (UAS) above populated areas in Germany. The tool generates predictions of possible fatalities in the event of a light Unmanned Aircraft crash through the use of validated statistics and considering the time and location of a mission. An example mission, including a discussion of the results, is provided to demonstrate and discuss the capabilities of O.R.C.U.S.

EASA’s Prototype Regulation on Unmanned Aircraft Operation makes a sound risk assessment of UAS flight operations indispensable. O.R.C.U.S. is able to increase risk awareness for operators and airworthiness authorities even if only less to none information about the UAS is available, supporting the possible approval of such an operation.

In this paper, O.R.C.U.S. is presented for the first time. O.R.C.U.S. can provide risk estimations for UAS operations in Germany, even if only minimum information about the UAS is available. In contrast to other tools, O.R.C.U.S. offers a unique risk prediction by combining aspects of the flying Unmanned Aircraft as well as the overflown area.

ADVANCED Aerodynamics & Structures Inc., (AASI) manufacturer of the Jetcruzer 450/500 single‐engine turbine powered aircraft, has applied for and seeks approval of change of certification standards in several countries for single‐engine turbine powered airplanes to engage in (RPI) Revenue Passenger Transport, during (IMC) Instrument Meteorological Conditions or IFR, and night operations.