MOC VTOL.2250(f) Aircraft capability after bird impact

• n/a found in: Small Category VCA (Revision 0) SC-VTOL (Oct 2024)

MOC VTOL.2250(f) Aircraft capability after bird impact n/a This MOC provides methods to demonstrate the remaining capability of the aircraft after a bird impact as required by [VTOL.2250](#_DxCrossRefBm1877490470)(f). It is applicable to VTOL capable Aircraft in the Category Basic designed to carry 7 to 9 passengers and in the Category Enhanced. **1. Single bird strike evaluation:** (a) In accordance with [VTOL.2250](#_DxCrossRefBm1877490470)(f), VTOL capable aircraft must be designed to ensure the capability of a controlled emergency landing in the Category Basic with a maximum of 7 or more seats, or of a continued safe flight and landing in the Category Enhanced, after impact of a 1.0-kg (2.2-lb) bird. This should be ensured in the most critical configuration for the corresponding velocity of the VTOL (relative to the bird along the flight path of the vehicle) up to the maximum speed in level flight with maximum continuous power, at operating altitude up to 2438 m (8,000 ft.). (b) Compliance should be shown by tests or by analysis based on tests carried out on sufficiently representative structures of a similar design. (c) The following parts should be evaluated for a single bird strike: (1) The windshield directly in front of occupants and the supporting structures for these panels should be capable of withstanding a bird impact without penetration for maximum speeds above 50kt. (2) Other structures, systems and equipment should also be evaluated. The selection of the areas to be substantiated should be the result of a comprehensive hazard analysis based on: (i) Exposed areas of the structure and internal equipment and systems inside of these exposed areas in case of bird penetration or shock loads; and (ii) Their criticality and their ability to ensure continued safe flight and landing (for Category Enhanced) or controlled emergency landing (for Category Basic). (d) When performing the hazard analysis, direct and induced effects of a bird strike should be considered: (1) "Direct Effects": to ensure the integrity of the structure and functionality of systems or equipment (including consideration of shock loads) which are critical for continued safe flight and landing (for Category Enhanced) or controlled emergency landing (for Category Basic). (2) "Induced Effects": to examine the possible consequences of the ejection of pieces from structures, systems or equipment which are struck by a bird on other structures and systems. For a bird impact on the lift/thrust system, the guidance in [MOC VTOL.2240(d)](#_DxCrossRefBm1877490476) can be followed, when relevant, in the demonstration of compliance mentioned in paragraph (a) of this section. **2. Multiple bird strike evaluation:** (a) VTOLs are generally equipped with redundant systems and structures. To ensure continued safe flight and landing (for Category Enhanced) or controlled emergency landing (for Category Basic) following a multiple bird strike, an evaluation should be performed of the effects of such multiple bird strike in the most critical configurations for the corresponding velocity of the VTOL up to the maximum speed in level flight with maximum continuous power, within the range of airspeed for normal operation up to 4000ft MSL (Mean sea level). (b) The applicant should consider potentially vulnerable redundant systems and structures and their effective exposed area (wing, lift surfaces, rudder, ailerons…). (c) An acceptable approach is to show that there is no loss of function of the element that is impacted after a single impact with a medium sized bird of 0.450 kg. Alternatively, scenarios evaluating multiple bird impacts distributed across each structure or system can be proposed by the applicant considering medium birds and small birds according to the [MOC VTOL.2400](#_DxCrossRefBm1877490486) guidance (see Figure 1). Multiple bird strike evaluation is not required for the windshield.  Figure 1- Overview of the Airframe and Propulsion System guidance interaction for compliance to bird strike