A gas turbine engine comprising: a compressor (44, 52); a combustor fluidly connected to the compressor (44, 52); a turbine (46, 54) fluidly connected to the combustor; at least one instrumentation egress incorporated in a compartment of said compressor (44, 52), combustor and turbine (46, 54); and an instrumentation adaptor incorporated in said at least one instrumentation egress, the instrumentation adaptor comprising: a seat; characterized in that the instrumentation adapter further comprises a seal contacting a surface of the seat and being constructed of a crushing seal material; a follower contacting said seal opposite said seat; a compressive component contacting said follower opposite said seal and including an exterior facing interface feature, wherein the compressive component is interfaced with an interior surface feature of the instrumentation egress, the seal is maintained in a compressed state via said compressive component, and a cooling tube is connected to said instrumentation egress, the cooling tube including a lead wire passage passing through the cooling tube for receiving one or more instrumentation lead wires; and a cooling fluid source, wherein an injection means is configured to inject cooling fluid from the cooling fluid source into an interior of the cooling tube, or passages in a wall of the cooling tube are configured to circulate cooling fluid received from the cooling fluid source. a compressor (44, 52); a combustor fluidly connected to the compressor (44, 52); a turbine (46, 54) fluidly connected to the combustor; at least one instrumentation egress incorporated in a compartment of said compressor (44, 52), combustor and turbine (46, 54); and an instrumentation adaptor incorporated in said at least one instrumentation egress, the instrumentation adaptor comprising: a seat; characterized in that the instrumentation adapter further comprises a seal contacting a surface of the seat and being constructed of a crushing seal material; a follower contacting said seal opposite said seat; a compressive component contacting said follower opposite said seal and including an exterior facing interface feature, wherein the compressive component is interfaced with an interior surface feature of the instrumentation egress, the seal is maintained in a compressed state via said compressive component, and a cooling tube is connected to said instrumentation egress, the cooling tube including a lead wire passage passing through the cooling tube for receiving one or more instrumentation lead wires; and a cooling fluid source, wherein an injection means is configured to inject cooling fluid from the cooling fluid source into an interior of the cooling tube, or passages in a wall of the cooling tube are configured to circulate cooling fluid received from the cooling fluid source. a seat; characterized in that the instrumentation adapter further comprises a seal contacting a surface of the seat and being constructed of a crushing seal material; a follower contacting said seal opposite said seat; a compressive component contacting said follower opposite said seal and including an exterior facing interface feature, wherein the compressive component is interfaced with an interior surface feature of the instrumentation egress, the seal is maintained in a compressed state via said compressive component, and a cooling tube is connected to said instrumentation egress, the cooling tube including a lead wire passage passing through the cooling tube for receiving one or more instrumentation lead wires; and a cooling fluid source, wherein an injection means is configured to inject cooling fluid from the cooling fluid source into an interior of the cooling tube, or passages in a wall of the cooling tube are configured to circulate cooling fluid received from the cooling fluid source.