Employment of Simulation for the Flight Certification of Rotorcraft

Abstract

The aim of this paper is to provide guidance on the employment of flight simulation to demonstrate, either directly or indirectly, compliance with the flight-related requirements within the certification standards for small or large rotorcraft. Herein are presented the approaches that are suggested in the guidelines for rotorcraft certification by simulation developed by the RoCS project to tackle the topic of the credibility of simulation. The term credibility is used to represent all the activities that should be performed to reach a sufficient level of confidence in the evidence gathered during simulated flight tests. To be in line with the certification standard requirements, the level of confidence should be comparable to that gained during a flight test. To build credibility it is necessary to take into consideration a detailed assessment of errors and uncertainties, both in the areas of validation of the model and in the ranges where extrapolation is applied, as well as a certain degree of conservatism when the level of uncertainty is not so small. The paper will illustrate the proposed approaches to credibility through the two examples of application of the guidelines: the assessment of controllability and maneuverability at low speed and the investigation of credibility for the quantification of dynamic stability.