Abstract: A gas turbine engine includes a plurality of annular discs arranged in an axial stack and defining axial passage, with at least one of the annular discs having an annular engagement member. A tie rod extends through the axial passage and secures the axial discs in the axial stack. The tie rod includes an annular collar defining an annular groove therein. The annular engagement member is received in the annular groove of the tie rod.

Abstract: A method and system for validating presence of a communication device in a confined area using a wireless local area network (WLAN) includes sending a first handshake message including a generated first key over a second network connection different from the WLAN connection by a device. A next step includes generating a second key to be returned to the device in a second handshake message over the same connection. A next step includes sending a WLAN probe request that has been modified to include the second key via the WLAN. A next step includes validating whether the device is present within the confined area using a second communication network; whereafter allowing communication access over the second network using both the first and second keys if the device is validated as being present within the confined area, and taking appropriate action if the device is not validated as being present within the confined area.

Abstract: A method and system for validating presence of a communication device in a confined area using a wireless local area network (WLAN) includes sending a first handshake message including a generated first key over a second network connection different from the WLAN connection by a device. A next step includes generating a second key to be returned to the device in a second handshake message over the same connection. A next step includes sending a WLAN probe request that has been modified to include the second key via the WLAN. A next step includes validating whether the device is present within the confined area using a second communication network; whereafter allowing communication access over the second network using both the first and second keys if the device is validated as being present within the confined area, and taking appropriate action if the device is not validated as being present within the confined area.