马航客机失联一个月，搜救工作仍在继续。目前的最新进展是，澳大利亚搜索船“海洋之盾”号在MH370疑似失事海域连续两次发现了符合黑匣子频率的脉冲信号，分别持续了140分钟和13分钟。联合协调中心总协调人安格斯•休斯顿认为，这是到目前为止搜索行动取得的最大进展，但确认信号与MH 370的关联性仍需时间。

飞机上的黑匣子到底是什么样的仪器，它都有哪些功能，我们一起来了解一下。

Black boxes - which are actually orange - are a group of data collection devices mounted in the tail of an aircraft.

黑匣子其实是橙色的，它是安装在飞机尾部的一组数据收集设备。

Under internationally agreed regulations, commercial aircraft must carry the equipment to record the performance and the condition of the aircraft in flight.

根据国际通行规定，商用飞机必须携带黑匣子来记录飞机在飞行过程中的性能和状况。

The recorders are housed in immensely strong materials, such as titanium, and insulated to withstand a crash impact many times the force of gravity, temperatures of more than 1,000 deg C for up to 30 minutes and the immense pressure of lying on the seabed.

这些记录仪都被装在钛等高强度的材料内，可以承受多倍重力强度的撞击，能在1000摄氏度以上的高温中耐受30分钟，还能承受沉入海底时的水下压力。

One manufacturing test for data recorders involves firing them from a cannon into a wall to simulate an aircraft suffering a catastrophic crash landing while traveling at hundreds of miles an hour.

生产这些数据记录仪时的测试之一就是用大炮将它们射向一面墙，来模拟飞机在以数百英里的时速飞行的情况下遭遇毁灭性坠毁着陆时的情景。

The recording material is itself insulated against accidental deletion and the corrosive effects of sea water.

记录仪本身的材料可以防止任何意外删除及海水腐蚀。

Modern black boxes record up to 300 factors of flight including:

现代黑匣子可以记录多达300中飞行数据，包括：

Airspeed and altitude

飞行速度和高度

Heading and vertical acceleration

航向及垂直加速度

Aircraft pitch

飞机俯仰

Cockpit conversations

驾驶舱对话

Radio communications

无线电通话

The safety precautions are designed to ensure, theoretically, that accident investigators will be able to recover the recorders, compile a full picture of an aircraft's last moments from the recordings and then accurately explain what went wrong.

理论上来说，这些安全防范措施是为了确保事故调查人员能找到这些记录仪，通过所有记录的内容了解到飞机在出事前最后时刻的整体状况，以便准确解释事故原因。