TOUGH AS HERCULES

TOUGH AS HERCULES

Landing gears to an aircraft are what claws are to an eagle. They are the only parts that support the entire aircraft when it takes off or lands.

起落架——撐起機身的大力士

人們常常羨慕雄鷹翱翔長空的灑脫，卻忽略了它們行走在陸地上的姿態。若拿振翅高飛的雄鷹比喻飛機，那么起落架便是那剛健有力的雙足。它是唯一一種支撐整架飛機的部件，因此是飛機不可或缺的一部份；沒有它，飛機便不能在地面移動。

Text and translation by Jean Lin Photos by Zeng Jian

Why do planes have feet?

1. To assist an aircraft in standing and parking, 2. To make an aircraft taxi when it takes off or lands 3. To withstand the gravitational forces when an aircraft lands and to shorten the stopping distance by the way of brake pads. Take the A380 or B747 for example, the four main landing gears need to bear the weight of 560 tons when the aircraft is still parked. The weight will sharply increase to 1000 tons when the plane taxis or accelerates forcefully.

飛機為什么要長腳？

1.支撐停放狀態的飛機；

2.起飛時的滑行；

3.著陸時承擔重力加速度，同時利用輪軸里的剎車片縮短滑跑距離。以380或者747為例，飛機靜止時，機身上的四個主起落架需要承受560頓的重量，而飛機加速滑行時，承受的重力則增至1000噸。

How Tough are They?

Take the A380 as an example, the mirror surface of the shock absorber is sprayed with liquid material under a temperature of about two thousand degrees, which greatly improves the hardness of the shock absorber. Meanwhile, the tyres are very special because they can endure temperatures below -40 degrees Celsius or above 71 degrees Celsius.

起落架的材質有多牛？

南航目前最大的客機A380的實用輪胎的載荷達了到每個能承受七萬磅之重的強度。這種輪胎的材質極為特殊，能夠承受-40℃以下和71℃以上的苛刻條件，其爆破壓力高于額定內壓4倍以上。

Two-axle, Four-wheel Main Gear of Boeing 787 Aircraft

波音787雙軸四輪主起落架

Landing gears help allocate average weight to each wheel. This greatly disperses the impact force generated by the contact between the wheels and the runway when the aircraft takes off and lands.

日趨完美的起落架結構及分布形態，不僅可將結構重量平均分配到每個輪子上，還可以分散飛機起飛降落時輪子與地面接觸時造成的沖擊力，同時也降低了對跑道的要求。

Most advanced aircraft nowadays adopt a “fly-by-wire system” and “avionics integrated system” to operate landing gears. These systems are more accurate and more efflcient.

目前起落架控制系統方面已經采用了電傳操縱技術和起落架電子綜合控制技術，通過計算機控制整個起落架的收放，從控制的角度而言，它更精確，效率更高，故障率更低，位置也更準確。

Wheel機輪

The airplane is equipped with wheels for taxiing on the runway. All wheels are installed with tubeless tyres, with good toughness and high durability. They help to absorb heat from impact or friction. Each wheel will bear up to 70,000 tons of load when the aircraft lands. They will also produce the necessary braking force to effectively stop the aircraft.