What type of bearing is commonly used for crankshaft main bearings in radial engines?

Crankshaft main bearings in radial engines typically utilize plain bearings. Plain bearings, sometimes referred to as bushings or sleeve bearings, consist of two flat surfaces sliding against each other and can handle the significant radial loads seen in engine operations. They provide a smooth surface for the crankshaft to rotate while accommodating the high forces and torque produced during engine operation.

In a radial engine, the design and function necessitate bearings that can handle both the loads and the unique stress distributions from the crankshaft's rotation. Plain bearings often excel in these areas because they can absorb shocks better than ball or roller bearings, which are generally suited for applications with different loading conditions.

Understanding the characteristics of plain bearings helps highlight their effectiveness in radial engines, making them the preferred choice for crankshaft support where high durability and resistance to wear are essential.