英语翻译the boeing 747 marked the beginning of a new era in air

英语翻译
the boeing 747 marked the beginning of a new era in air transport,the jumbo-age.the jumbo carries about three times as many passengers.as a boeing 707 and its cargo capacity is three times the capacity of the 707 s.the first air china jumbo went into service in april l987 and there are about ten of these wide-body jets with the flying crane symbol on their fins.air china has replaced the older 747 s with the latest models which need less fuel and have increased engine power.
the four huge engines consume about 14500 liters of kerosene per hour.the air intake of the engines has a diameter of 2.19 meters.to mention a couple of other facts,the artificial horizon shows the pilot the aircraft s position in flight at any time.this is particularly important when visibility is low due to clouds or haze.the aircraft s weather radar equipment tells the pilot whether the clouds ahead are harmless or whether they hide possible turbulence.
there are three different versions of the 747.they all have a wing-span of 59.64 meters and a length of 70.51 meters.the take-off weights,however,vary from 333 to 362 metric tons.the air china passenger versions have room for up to 361 people to be carried over a maximum distance of 9800 kilometers.the combi-version,the 747 sl,has 249 seats and an additional freight compartment for six freight pallets aft of the passenger cabin.a special side cargo door allows quick and easy access to this cargo compartment.all jumbos provide further stowage for freight in their bellies underneath the cabin.
the giant air freighter,which is loaded from the front by means of a hinged nose which moves upwards,and a side cargo door in the rear,was operated by air china in 1983.this jumbo freighter can carry about 100 metric tons of freight.the weight,which can be up to 362 metric tons,is supported by four main landing gears with four wheels each and a nose gear with two wheels.this means that each set of wheels puts less weight on the runway than those of a 707.which has half the total weight of the jumbo.

波音747的出现标志着空中运输业的新纪元的开始——这就是大型飞机时代.
大型飞机能搭乘3倍于波音707客机的乘客,同时它的货运装载能力也是707的3倍.
1987年4月,首批在中国国航投入使用的是大约十架这种尾翼上有飞鹤标志的宽体喷气式客机,国航已经用最新的型号替换了较早的747机型,这些新机型油耗更低,发动机的功率更大.
4个巨大的引擎每小时消耗航空燃油14500升,引擎的进气口直径达到了2.19米.值得一提其他特点包括,虚拟地平线系统可以在飞行中全时向飞行员提供飞机的位置信息,这在由于云层或雾造成的能见度降低时显得尤为重要；飞机的气象雷达能告知飞行员云层到底是无害的还是隐藏着气流扰动.
一共有三个型号的747型飞机,它们的翼展都达到了59.64米,长度为70.51米.最大起飞重量从333吨到362吨.国航选用客机型号拥有最大可容纳361座的空间,最大航程为9800公里.混合型的747sl型客机,则有249个座位和一个位于客舱后部的内置6个货盘的货舱,一个位于机身侧面的货舱门能快速方便地装卸货物.所有机型都提供了一个位于机身腹部的更大的货舱.
1983年开始投入国航运营的这种巨型运输机,通过机头上一个用铰链链接,向上开启的舱门,和位于机身后部的一个舱门装载货物.这些巨型运输机可以装载大约100吨的货物,它们的最大起飞重量达到362吨,这些重量全部支撑在4个分别拥有4个轮胎的主起落装置和一个位于机头的2轮起落装置上,这意味着分担在每个轮胎上的重量比波音707还要轻,而707的总重量还不到747的一半.