Mast bumping is something that can occur with some types of helicopters. Here's exactly what it is, what causes it, and how ...

Mast bumping is a critical and often fatal phenomenon in helicopters, particularly those with two-bladed main rotors like Robinson and certain Bell models, occurring when the main rotor is "unloaded" ...

An interim report into the fatal crash of a Robinson R44 helicopter in Northland in October has found it is "very unlikely" ...