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The ISO TC22/SWG2 - Brake Lining Committee established a task force to determine and analyze root causes for variability during dynamometer brake performance testing. SAE paper 2010-01-1697 “Brake Dynamometer Test Variability - Analysis of Root Causes” [1] presents the findings from the phases 1 and 2 of the “Test Variability Project.” The task force was created to address the issue of test variability and to establish possible ways to improve test-to-test and lab-to-lab correlation. This paper presents the findings from phase 3 of this effort-description of factors influencing test variability based on DOE study. This phase concentrated on both qualitative and quantitative description of the factors influencing friction coefficient measurements during dynamometer testing.

Typical design challenges for Unmanned Aerial Vehicles (UAVs) require low aerodynamic drag and structural weight. Both of these requirements imply that these aircraft are considerably more flexible than conventional aircraft and their stability analyses are more complex since they require models unifying rigid body and elastic dynamics. This paper aims to built such a model for a generic UAV. The model is then used to address stability in terms of divergence and flutter.

In the future, it will be possible to manufacture very small, robust machines, which may be attached to the surface of a wing allowing the classic boundary condition of “no-slip” to be altered at will. It is also possible that the heat transfer through the wing surface can be controlled. This paper reports an investigation into the possible benefits to aerodynamics that will occur if such machines become available. It is found that imposing an isothermal wing surface can increase the lift drag ratio of wing at transonic cruise and allowing slip at the surface can have the same effect. Both these effects are additive. It is found that control of heat transfer on a wing at hypersonic wing can act as a control device, comparable to that due a moderate flap deflection.

Hydraulic fluids of the HFC category are aqueous polymer solutions with a fire resistance enhancing water content of 35 to approx. 50 %. The use of HFC fluids, above all in mobile and stationary drives in mining and in casting is subject to restrictions resulting from a number of features of a fluid. Field practice has shown that while axial-piston pumps may be successfully operated using HFC fluids, rolling bearing failures reduce their operational lifetimes. The bearing failures essentially result from material fatigue. This can be remedied by new quality steel for roller bearings. The combination of high fatigue life and corrosion resistance assures a wide application range for nitrogen-treated steel qualities.