Abstract. The paint coating protects the metal structure of an aircraft from corrosion and consists of several functional layers (primer, filler, lacquer, enamel, paint, and others). The protective properties and durability of the paint coating are determined by its thickness, which is the primary quality indicator. Automated pneumatic spraying is used to apply coating materials to aircraft surfaces. Ensuring uniform paint coating thickness in automated pneumatic spraying is an important practical problem. The uniformity of paint coating thickness is determined by a combination of process parameter values that define the operating conditions of automated equipment over a prescribed time. A method is proposed for calculating the interrelated process parameters of automated pneumatic spraying to achieve a uniform-thickness paint coating. The effect of the spray regime on the thickness and uniformity of the paint coating is shown. Expressions are presented for estimating the air flow velocity along the spray cone axis, the air flow rate, the coating material flow rate, and the size of atomized droplets. The formation of a coating material layer on the surface being coated is considered; the layer consists of partially overlapping passes, each having a normal thickness distribution in cross-section. Expressions are given for estimating the waviness of the coating material layer surface. Expressions are presented for determining the optimal sprayer feed rate and the sprayer traverse speed along the applied pass that ensure minimal waviness of the coating material layer surface. An overlap coefficient for adjacent coating material passes is introduced, relating the optimal sprayer feed rate to the standard deviation that characterizes the spray spot diameter of the spray cone. An example is presented showing the effect of spray distance on the spray spot diameter, the optimal feed rate, and the sprayer traverse speed in automated pneumatic spraying of a uniform-thickness paint coating. The coating material layer thicknesses at the peaks and valleys of its surface are determined. The uniformity of paint coating thickness in automated pneumatic spraying is ensured by a combination of process parameter values; their interdependence is established.

Keywords: corrosion protection of aircraft, paint coating, coating material, pneumatic spraying, coating thickness uniformity, automated spraying

For citation: Andryushkin A. Yu., Pivovarov A. A., Yablokov D. V. Ensuring uniform paint coating thickness on an aircraft by automated pneumatic spraying. Aerospace Engineering and Technology. 2026. Vol. 4, no. 1, pp. 166–181. (In Russ.) https://doi.org/10.52467/2949-401X-2026-4-1-166-181; https://elibrary.ru/SSORAU

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