Antiwear properties of fuels for airbreathing jet engines (AJE) based on three types of rapeseed-oil biocomponents and their blends are studied experimentally. It is shown that the biocomponents are much better lubricants than conventional petroleum fuels for AJE. The studies found that additionof biocomponents to aviation fuel strengthens boundary layers and thereby improves the antiwear properties of the fuel blends. It is demonstrated that additional modification of the biocomponents enhances their lubricating capacity with respect to standard rapeseed-oil components.