Abstract: A gas turbine engine rotor assembly, comprising: a shaft about an axis having an outer surface radially outward and a groove radially into the outer surface; a disc surrounding the shaft rotatable with the shaft about the axis, the disc having an inner surface extending axially defining an inner diameter, having a disc profile around the groove and axially away from and radially inwardly of the inner diameter, the shaft and the disc defining a gap circumscribed outwardly by the inner diameter and inwardly by the outer surface; and a seal including a split ring fitted into the groove and rotatable with the shaft about the axis, the ring having a ring profile complementary to the disc profile, the ring resiliently expandable radially in the gap to the inner diameter, the disc profile cooperable with the ring profile to axially load the shaft via the ring expanded across the gap.

Abstract: A gas turbine engine rotor assembly, comprising: a shaft about an axis having an outer surface radially outward and a groove radially into the outer surface; a disc surrounding the shaft rotatable with the shaft about the axis, the disc having an inner surface extending axially defining an inner diameter, having a disc profile around the groove and axially away from and radially inwardly of the inner diameter, the shaft and the disc defining a gap circumscribed outwardly by the inner diameter and inwardly by the outer surface; and a seal including a split ring fitted into the groove and rotatable with the shaft about the axis, the ring having a ring profile complementary to the disc profile, the ring resiliently expandable radially in the gap to the inner diameter, the disc profile cooperable with the ring profile to axially load the shaft via the ring expanded across the gap.

Abstract: There is described a shaft shear event detection method. The method comprises storing in memory a shaft oscillation signature determined as a function of known characteristics of the shaft and associated with a shaft shear event; monitoring a rotational speed of the shaft; detecting from the rotational speed an oscillation wave superimposed on the rotational speed by detecting a first period below a lower threshold and a second period above an upper threshold, and detecting a rate of occurrence of the first period and the second period, the oscillation wave having a wave modulation frequency corresponding to the rate of occurrence and a wave modulation amplitude; comparing the oscillation signature to the oscillation wave; and detecting the shaft shear event when the oscillation wave corresponds to the oscillation signature.

Abstract: There is described a shaft shear event detection method. The method comprises storing in memory a shaft oscillation signature determined as a function of known characteristics of the shaft and associated with a shaft shear event; monitoring a rotational speed of the shaft; detecting from the rotational speed an oscillation wave superimposed on the rotational speed by detecting a first period below a lower threshold and a second period above an upper threshold, and detecting a rate of occurrence of the first period and the second period, the oscillation wave having a wave modulation frequency corresponding to the rate of occurrence and a wave modulation amplitude; comparing the oscillation signature to the oscillation wave; and detecting the shaft shear event when the oscillation wave corresponds to the oscillation signature.

Abstract: There is described a shaft shear event detection method. The method comprises storing in memory a shaft oscillation signature determined as a function of known characteristics of the shaft and associated with a shaft shear event; monitoring a rotational speed of the shaft; detecting from the rotational speed an oscillation wave superimposed on the rotational speed, the oscillation wave having a wave modulation frequency and a wave modulation amplitude; comparing the oscillation signature to the oscillation wave; and detecting the shaft shear event when the oscillation wave corresponds to the oscillation signature.

Abstract: A method of balancing a spool of a gas turbine engine, the spool including a forward rotor assembly and an aft rotor assembly separated by a spacer, the method comprising: balancing the forward rotor assembly and the aft rotor assembly independently from one another using conventional balancing techniques; and mathematically modeling the spool; applying a modeled axial load to the modeled spool to determine a trim weight which would balance the spool when subjected to the modeled axial load; and physically placing the trim weight to one of the forward rotor assembly and the aft rotor assembly.

Abstract: There is described a shaft shear event detection method. The method comprises storing in memory a shaft oscillation signature determined as a function of known characteristics of the shaft and associated with a shaft shear event; monitoring a rotational speed of the shaft; detecting from the rotational speed an oscillation wave superimposed on the rotational speed, the oscillation wave having a wave modulation frequency and a wave modulation amplitude; comparing the oscillation signature to the oscillation wave; and detecting the shaft shear event when the oscillation wave corresponds to the oscillation signature.

Abstract: A cam-type apparatus is included in a support link between outer and inner cases of gas turbine engines for centering the cases one to another. The cam-type apparatus is lockable to allow locking an adjusted position of the cam-type apparatus.

Abstract: A cam-type apparatus is included in a support link between outer and inner cases of gas turbine engines for centering the cases one to another. The cam-type apparatus is lockable to allow locking an adjusted position of the cam-type apparatus.

Abstract: A method of balancing a spool of a gas turbine engine, the spool including a forward rotor assembly and an aft rotor assembly separated by a spacer, the method comprising: balancing the forward rotor assembly and the aft rotor assembly independently from one another using conventional balancing techniques; and mathematically modeling the spool; applying a modeled axial load to the modeled spool to determine a trim weight which would balance the spool when subjected to the modeled axial load; and physically placing the trim weight to one of the forward rotor assembly and the aft rotor assembly.

Abstract: A gas turbine engine has a rear mounting structure incorporating a mounting apparatus attached to a bypass duct wall with a link device of six rods for transferring core portion related inertia-induced loads, from an inner case of the core portion in a short circuit across an annular bypass air passage to the bypass duct wall.

Abstract: A cam-type apparatus is included in a support link between outer and inner cases of gas turbine engines for centering the cases one to another. The cam-type apparatus is lockable to allow locking an adjusted position of the cam-type apparatus.

Abstract: A gas turbine engine has a rear mounting assembly incorporating a mounting apparatus attached to a bypass duct wall with a link device for transferring core portion related inertia-induced loads, from an MTF of the core portion in a short circuit across an annular bypass air passage to the bypass duct wall.

Abstract: A containment system for containing fragments of a burst rotor including first and second means for frangibly connecting a containment element to first and second walls, the first and second means rupturing upon being subjected to a load mainly produced by a translational motion of at least one fragment impacting the element.

Abstract: A gas turbine engine has a rear mounting structure incorporating a mounting apparatus attached to a bypass duct wall with a link device of six rods for transferring core portion related inertia-induced loads, from an inner case of the core portion in a short circuit across an annular bypass air passage to the bypass duct wall.

Abstract: A containment system for containing fragments of a burst rotor including first and second means for frangibly connecting a containment element to first and second walls, the first and second means rupturing upon being subjected to a load mainly produced by a translational motion of at least one fragment impacting the element.

Abstract: A containment system for containing fragments of a burst rotor including first and second means for frangibly connecting a containment element to first and second walls, the first and second means rupturing upon being subjected to a load mainly produced by a translational motion of at least one fragment impacting the element.

Abstract: A cam-type apparatus is included in a support link between outer and inner cases of gas turbine engines for centering the cases one to another. The cam-type apparatus is lockable to allow locking an adjusted position of the cam-type apparatus.

Abstract: A gas turbine engine has a rear mounting assembly incorporating a mounting apparatus attached to a bypass duct wall with a link device for transferring core portion related inertia-induced loads, from an MTF of the core portion in a short circuit across an annular bypass air passage to the bypass duct wall.