concern here is the cavity 38 that is located adjacent the aft wall 26 fig2 and 3 illustrate the close proximity of the cavity 38 to the aft shank wall 26 with a relatively thin ligament 48 therebetween fig3 also illustrates the manner in which adjacent buckets 10 and 110 are closely aligned when mounted on a turbine wheel with respective corner edges 40 42 of bucket 10 closely aligned with corner edges 140 142 of bucket 110 the space between side surfaces 44 and 144 may be on the order of about 0 040 inch and as mentioned above seal pins not shown are typically located within this space to prevent leakage between the adjacent buckets specifically there are two seal pins one oriented horizontally as mentioned above and the other oriented radially mating between radial surfaces adjacent to edges 42 and 142 of fig3 fig4 is similar to fig3 but also shows the airfoil portions 18 118 of the respective buckets 10 110 of note in this figure is the extent of overhang of the trailing edge 32 relative to the aft shank wall 26 it will be appreciated that simply extending the aft wall to increase the width of ligament 48 between cavity 38 and the aft shank wall 26 would impair the ability to have an acceptable.