Definition
(Propeller) These are generally not known. Analytical estimating techniques used by Landing Products to quantify torsional acceleration loads suggest that they can become dominant when pre-ignition or detonation occurs. These observations are supported by test experience with very high-performance engines running at elevated temperatures. Such conditions cause high torsional loads (about the engine shaft) which create high bending stresses, adding to those from centrifugal force and lift/drag effects. These loads depend on unique conditions for specific engines, especially those "hopped up" for racing, where lean mixtures lead to high cylinder temperatures and pre-ignition/detonation.