Abstract: Methods and systems for aircraft engine trend monitoring include periodically recording the outputs of engine-condition sensors and analyzing the results to examine piston-engine performance trends and predict the need for engine maintenance. Various analyses can be performed, separately or in parallel, including comparing the current parameter values with values recorded for that parameter in previous instances of similar operating conditions; comparing parameter values to predetermined nominal ranges; and detecting parameter values that exhibit trends over time that if followed would result in out-of-bound readings. Sensed parameter values can also be used to detect when recommended engine operating conditions are being exceeded.

Abstract: A lubrication system for an overriding starter clutch assembly includes an axial input passage through the clutch shaft to radial passages supplying the oil to the inlet of the clutch working unit. A centrifugal pump created by vanes in the clutch housing end face pulls the lubricating oil axially through the clutch.

Abstract: An improved cooling system for an internal combustion aircraft engine having horizontally opposed cylinders. The cooling system comprises a coolant design which delivers and removes coolant in a parallel circuit. The coolant flows from a common main coolant inlet line which branches into two secondary inlet lines. Each secondary inlet line has fitted thereto a number of cylinder inlet lines which branch off from the secondary inlet line to each deliver coolant to their respective cylinder. The heated coolant is removed via cylinder coolant outlet lines fitted to each cylinder. The cylinder outlet lines fluidly interconnect one of two secondary outlet lines. The secondary outlet lines combine into one main outlet line for delivery to a ram air cooled heat exchanger to begin the process again. To further assist in cooling, coolant enters the head portion of the cylinder and exits from the intermediate portion, thereby directing the coolest fluid first to the hottest portion of the cylinder.

Abstract: An exhaust manifold for multi-cylinder, opposed piston engines includes a collector, a plurality of conduits, each connecting an exhaust port from a cylinder to the collector and each conduit includes a thermal expansion joint to permit differential thermal expansion between the engine body and the substantially hotter exhaust conduit and thus to avoid undesirable stresses in the conduits. Preferably, the expansion joint is formed by overlapping portions of conduit sections which include axial as well as radial clearances therebetween for thermal expansion. In the event that the engine is to be turbocharged, the manifold can be covered with a thermal blanket to prevent heat losses from the exhaust system. In such a case, the expansion joint includes a resilient seal member between the overlapping conduit portions which seals the conduit sections to each other despite substantially similar thermal growth in each of the insulated blanketed conduit sections.

Abstract: The present invention provides an improved cooling system for a reciprocating piston engine. The engine is of the type having at least one cylinder and a piston movable between a top dead and bottom dead center. The cooling system comprises a housing or coolant jacket which encircles the outer end of the cylinder and extends towards the inner end of the cylinder. The coolant jacket, however, terminates short of the inner end of the piston when the piston is at its top dead position. A fluid passageway is formed through the housing and has both an inlet and outlet. Liquid coolant is supplied under pressure to the inlet port on the housing. The coolant flows through the lower section of the water jacket surrounding the piston area thus achieving uniform adequate cooling of both the combustion chamber and piston.