Abstract: A total temperature probe comprising a hollow elongate shroud defined by a shroud wall that envelops a first cavity. The shroud wall is comprised of an inner skin and an outer skin which enclose a second cavity therebetween. A temperature sensor mounted in the first cavity. In use, fluid flow is received into the first cavity, passes through at least one aperture in the inner skin into the second cavity and then passes out of the shroud through at least one aperture in the outer skin. Beneficially, heat conduction across the inner skin is minimal.

Abstract: A method to determine shaft stiffness of a rotating shaft, the shaft coupling a turbine to drive the rotation and a load to be driven by the rotation. For a given operational temperature and rotational speed of the shaft, the method including steps to determine polar moments of inertia of the load and the turbine. Determine natural torsional vibration frequency of the shaft. Determine the shaft stiffness by calculation using the inertias and vibration frequency.

Abstract: A total temperature probe comprising a hollow elongate shroud defined by a shroud wall that envelops a first cavity. The shroud wall is comprised of an inner skin and an outer skin which enclose a second cavity therebetween. A temperature sensor mounted in the first cavity. In use, fluid flow is received into the first cavity, passes through at least one aperture in the inner skin into the second cavity and thence passes out of the shroud through at least one aperture in the outer skin. Beneficially, heat conduction across the inner skin is minimal.