As soon as we hear the usual call from the flight deck, 'Cabin crew...prepare for landing', we know that it's part of the preparation for a passenger plane's arrival at its destination and one of the most important stages of any flight. What goes up…must come down (smoothly and securely), yet something we possibly take for granted is the performance and reliability of today’s aviation landing gear technology.
The landing gear is quite a "big deal" in terms of size and cost as it is regarded as a "mechanical marvel" by some aviation experts. For instance, it’s estimated by the world’s top airline manufacturers to signify around 20% of the total aircraft maintenance and around 7% of the total weight of the aircraft. In another example, the maximum take-off weight of an Airbus A320 (one of the biggest selling aircrafts today with over 16,000 flights) is approximately 83,000 kg (183,000 lbs.), of which around 5500 kg (12125 lbs.) is the weight of the landing gear.
The landing gear is typically manufactured by speciality suppliers to the aviation industry, who then supply to prominent large manufacturers. This is because the landing gear and shock absorption are recognized as separate fields of science when compared to other aspects of aviation technology.
Specialist bearings are an essential component of innovative landing gear systems, particularly with applications involving landing gear struts and actuators. Precision bearing specialists, CARTER MANUFACTURING LTD. are approved aerospace bearing suppliers to industry-leading landing gear manufacturers. With their key focus being high quality and customer satisfaction, they have been accredited to ISO9001 incorporating the requirements of AS9120 with flow down from AS9100. As required, their bearings also comprise AS9120 Aerospace First Article inspection reports for tracking of all raw materials and specific procedures along with full dimensional analysis.
One of the most substantial issues with landing gear components, while installing or maintaining them, is their size and the risks connected with transferring them between departments.
Carter offer specialised and customised aerospace portable bearing tools to ease pressures, such as clearance constraints and anti-rotation features that have been proved through decades of expertise and thousands of successful projects. The safe removal, installation, and testing of bearings are also enabled by using a portable set of tooling, without moving the component.
Most landing gear systems have the bearings positioned at the end of a very long and heavy tube with restricted access, which necessitates the development of unique fixtures to guarantee the component is square and fastened to the hydraulic press or vertical milling machine. This problem can easily be solved by using portable tools. For instance, a staking force for a 4" OD bearing would be approximately 50,000 lbs., while the swaging force for portable tools is so low that it may simply be applied by hand, with a wrench.
Carter’s swaging tools are precision-engineered to fit specific landing gear bearings, lowering operational risks and costs by reducing the likelihood of damaging expensive bearings and housings. In case a particular application requires a different approach or the customer doesn’t wish to use portable tools, the drill press style swaging tools are a much better alternative than the anvil staking tools. This is because the required swaging force is just a fraction of the overall staking force and will radically improve the quality of the swage.
Carter Manufacturing Ltd. also support projects by validating theoretical bearing performance through their proprietary bearing application software. They also provide comprehensive reports to educate their customers and validate mission critical decisions.