An instrumentation assembly configured to measure properties of an engine exhaust stream is disclosed in this paper. The instrumentation assembly may include an outer support ring that extends around a central axis, an inner support ring arranged radially inward of the outer support ring around the central axis, and a plurality of instrumentation rake assemblies. The plurality of instrumentation rake assemblies extends from the outer support ring to the inner support ring across an annular passageway defined between the outer support ring and the inner support ring configured to carry the engine exhaust stream.