ISO INTERNATIONAL STANDARD 1151-5 Second edition 1987-05-01 INTERNATIONALORGANIZATION FOR STANDARDIZATION ORGANISATION INTERNATIONALE DE NORMALISATION MEXKAYHAPOAHAA OPTAHM3ALMH HO CTAHAAPTW3AUMW Flight dynamics - Concepts, quantities and symbols Part 5: Quantities used in measurements Mécanique du vol - Concepts, grandeurs et symboles -- Partie5:Grandeursutiliséesdans les mesures "The American National Standards Institute (ANSl) is the primary source and official sales distribute and sell iso standards, technical reports, drafts and other priced publications reproduce isO standards and drafts within the territories of the United States". Reference number ISO 1151-5 : 1987 (E) Not for Resale Foreword national standards bodies (isO member bodies) The work of preparing International Standards is normally carried out through iso technical committees. Each member body interested in a subject for which a technicat committee has been established has the right to be represented on that committee. International organizations, govern- mental and non-governmental, in liaison with iSo, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISO Council. They are approved in accordance with ISO procedures requiring at least 75 % approval by the member bodies voting. International Standard ISO 1151-5 was prepared by Technical Committee ISO/TC 20, Aircraft and space vehicles. This second edition cancels and replaces the first edition (IS0 1151-5 : 1974), of which it constitutes an overall technical revision and to which sub-clause 5.7 has been added. Users should note that all International Standards undergo revision from time to time and that any reference made herein to any other International Standard implies its iatest edition, unless otherwise stated. ? International Organization for Standardization, 1987 Printed in Switzerland 11 Copyright International Organization for Standardization ed without license from IHS Not for Resale ISO 1151-5 : 1987 (E) Iso 1151, Flight dynamics -- Concepts, quantities and symbols, comprises, at present, seven parts: Part 1: Aircraft motion relative to the air. Part 2: Motions of the aircraft and the atmosphere relative to the Earth Part 3: Derivatives of forces, moments and their coefficients. Part 4: Parameters used in the study of aircraft stability and control. Part5:Quantitiesused inmeasurements. Part 6: Aircraft geometry. Part 7: Flight points and flight envelopes. iso 1151 is intended to introduce the main concepts, to include the more important terms used in theoretical and experimental studies and, as far as possible, to give cor- responding symbols. In all the parts comprising Iso 1151, the term "aircraft" denotes a vehicle intended for atmosphere or space flight. Usually, it has an essentially port and starboard symmetry the aircraft. In that plane, two orthogonal directions are defined: fore-and-aft and dorsal-ventral. The transverse direction, on the perpendicular to that plane, follows. When there is a single plane of symmetry, it is the reference plane of the aircraft. When there is more than one plane of symmetry, or when there is none, it is necessary to choose a reference plane. In the former case, the reference plane is one of the planes of symmetry. In the latter case, the reference plane is arbitrary. In all cases, it is necessary to specify the choice made. Angles of rotation, angular velocities and moments about any axis are positive clockwise when viewed in the positive direction of that axis. All the axis systems used are three-dimensional, orthogonal and right-handed, which implies that a positive rotation through x/2 around the x-axis brings the y-axis into the position previously occupied by the z-axis. The centre of gravity coincides with the centre of mass if the field of gravity, is homogeneous. If this is not the case, the centre