Polar residues of TMD2 influence ionic permeability of recombinant ATP - gated P2X2 receptors

An aircraft engine installation is disclosed wherein a gas turbine engine is supported within the interior of a tubular cowling that is affixed to the aircraft and all other components of the engine installation such as an air inlet and exhaust system structurally depend from the cowling rather than being mounted to the gas turbine engine. To permit access to the engine for inspection, repair or removal. the lower portion of the cowling is linked to a stationary upper portion of the cowling by a set of jackscrew assemblies spaced apart along each axial boundary of the upper and lower cowling units. The jackscrew assemblies are operable to lower the lower cowling unit to a position at which integral locks, included in one set of the jackscrews, can be released to permit the lower cowling unit to be swung open about integral hinges that are included in the second set of jackscrews. A powered actuator system, mounted within the upper cowling unit, is operable to swing the lower cowling unit about the hinges to open or close the cowling and can also be utilized to raise and lower the gas turbine engine between the upper cowling unit and ground level during an engine change operation. To securely fasten the upper and lower cowling units together whenever the cowling is closed, interlock assemblies are included along each of the mating boundaries of the two cowling units. In one disclosed arrangement, the interlock assemblies of each individual pair of boundaries are operated in unison by a geared drive system and both sets of jackscrews are operated in unison by a second geared drive system. In an alternative arrangement, a drive system is included which can be selectively operatied to activate either the interlock assemblies or both sets of jackscrews. To provide a visual indication that the lower cowling unit is not securely latched to the upper cowling unit, warning flags are arranged to project from the exterior surface of the cowling unless the interlocks are in a fully closed condition.