This specification establishes the requirements for the instrumentation aspects of airworthiness and design for "small" aircraft. It prescribes the Aircraft Type Code (ATC) compliance matrix based on airworthiness level, number of engines, type of engine(s), stall speed, cruise speed, meteorological conditions, altitude, and maneuvers. An ATC is defined by taking into account both the technical considerations regarding the design of the aircraft and the airworthiness level established based upon risk-based criteria. The instrumentation requirements established by this specification cover flight and navigation instruments, electronic display instrument systems, airspeed indicating system, static pressure system, magnetic direction indicator, and instruments using a power source.
1.1 This specification covers flight and navigation instrumentation aspects of airworthiness and design. The material was developed through open consensus of international experts in general aviation. This information was created by focusing on Level 1, 2, 3, and 4 Normal Category aeroplanes; however, the content may be more broadly applicable, and should not be unduly limited. The topics covered within this specification are flight and navigation instruments including those for airspeed, altitude, attitude, heading, free air temperature, and speed warning.
1.2 The applicant for a design approval shall seek the individual guidance of their respective CAA body concerning the use of this specification as part of a certification plan. For information on which CAA regulatory bodies have accepted this specification (in whole or in part) as a means of compliance to their Small Aircraft Airworthiness regulations (hereinafter referred to as “the Rules”), refer to ASTM F44 webpage (www.ASTM.org/COMMITTEE/F44.htm), which includes CAA website links. maps the means of compliance described in this specification to EASA CS 23, amendment 5 or later, and FAA 14 CFR 23, amendment 64 or later.
1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.