Airframe Needle and Roller Bearings: Toughness at 33,000 Feet
As part of our Bearings 101 series of informational articles, we’re highlighting types of bearings or bearing components. Next on the agenda are airframe control needle and roller bearings.
Regardless of the application, you always want a bearing to be sturdy and reliable. But when it comes to components for aircraft, the margin for error is almost nonexistent. Passengers, air freight customers, and pilots need to trust every piece of the plane or helicopter they use. For a Boeing 747, that’s six million components, many of which are airframe control needle and roller bearings.
Although flying is one of the fastest ways to travel, airframe control bearings generally spin at medium or low RPMs. The greatest demand on needle and roller bearings in aircraft is load. A 747 can weigh up to 378 tons at maximum takeoff weight. Roller bearings in a plane’s landing gear bear its full weight across just a few wheels, so they need to be tough! Despite the high loads these bearings must carry, they must also be light enough to ease takeoff and conserve fuel. Finally, they need to function well at the frigid temperatures of cruising altitude.
There are two main types of bearings in aircraft.
- Aircraft roller bearings typically have a cylindrical or tapered shape. They reduce friction in places like jet engine shafts and gear boxes, landing wheels, and helicopter transmissions.
- Aircraft needle bearings are roller bearings with long, skinny rollers. Their design makes them resistant to high, vibrating loads. They are mostly found in wing slat and flap carriages, but also show up in door mechanisms and support struts for landing gear.
For help selecting aircraft bearings, advice about your specific design requirements, or to order bearings, contact one of our sales engineers.
Have you seen our other Bearings 101 articles? Here are our pieces on thin section bearings, roller bearings, Thinex and torque tube bearings, machine tool spindle bearings, deep groove bearings, a comparison of bushings to bearings, and our bearing glossary.
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