Solving the age-long problem of tool stability when drilling in deep cavities alongside tall shoulders, and past bulky fixtures, Kennametal has the answer. Reaching deep inside a workpiece to drill holes can be a real bear. You´ve tried taper length and aircraft drills, but even those made of solid carbide are apt to wander when hanging out of the chuck unsupported. Maybe you´ve combatted the problem with special extended-reach drill holders, although these are not only expensive, but limited to specific fixed lengths.