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The standard air flow velocity measurement procedure has been developed in order to unify and standardize the measuring instruments used and data processing algorithms, reduce the development time and certify such standard methods. Sources of error in indirect measurements of air flow velocity in the range 3–105 m/s are investigated. The sources of instrumental error of indirect measurements are analyzed – pressure sensors with digital and analog output signals, pitot tube, temperature and relative air humidity sensors, atmospheric pressure sensors. It is shown that the greatest contribution to the instrumental error is made by measuring the pressure difference and atmospheric pressure. The errors of method, which depends on the measurement model, is considered. A new mathematical model of measurements is proposed, which includes optimal expressions for determining the density of moist air and corrections for compressibility and allows to reduce the methodological error, and requirements for the metrological characteristics of the measuring instruments used are developed, ensuring that the total error of indirect measurements of the flow velocity complies with the allowable limits of ±0,2 m/s. Recommendations are given on the use of measuring instruments and algorithms for processing measurement results, which make it possible to reduce the measurement error by 39 % and develop a standard air flow velocity measurement procedure. The standard procedure is relevant for aviation industry enterprises, where the air flow rate is measured by the pneumometric method.

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A system of metrological support is proposed that allows testing for type approval, verification and calibration of stands for measuring mass, coordinates of mass center and moments of inertia. The mathematical model of a special standard has been developed. It is based on the analytical principles for the determination of the mass center coordinates and inertia moments of homogeneous bodies with a regular geometric shape. The standard consists of a set of modules and fasteners of a special shape. Each module is a reference measure of both mass, center of mass coordinates, and moments of inertia, and can be used either separately or in a set with other modules. A scheme for transferring units of values from state primary standards of mass and length to stands using special standards has been developed. A method for calibration of special standards has been developed. It includes indirect measurements of the coordinates of the center of mass and moments of inertia based on the results of direct measurements of the mass and geometric dimensions of the standard modules’ elements, as well as measurements of the form deviations and deviations of position of the standard modules’ surfaces and static balancing of the standard. Technical requirements for special standards have been developed to minimize methodological measurement uncertainties when reproducing units of values by the standard. A line of special standards was created, their certification and approval in Rosstandart was carried out. Stand verification methods using special standards have been developed and approved. The type approval of two stands was carried out using special standards. The decision to grant a patent for the invention “Method for determining the error of the stand for measuring the characteristics of the mass geometry of products and a device for its implementation” was received.

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