黑匣子的秘密：空難的真相記錄者

On the minds of many these days is the mystery of Malaysia Airlines lost flight MH370， a Boeing 777 that disappeared on March 8th. How does a plane just disappear into thin air？ Recovering the flight data recorder （FDR）， otherwise known as the flight’s black box （even though it is really orange）， might be the only way to solve the plane’s mysterious disappearance. This got me wondering： just how does a black box containing 1）electronic circuit boards remain intact during a 2）catastrophic airplane crash？ The truth is that the electronics are likely destroyed， but the recorded data is recoverable.

In fact， there are two data recording devices on-board an airplane： the cockpit voice recorder（CVR） that records dialogue in the cockpit such as communications between the pilots with air traffic control， and the FDR that records hundreds of different 3）parameters about the airplane while in flight. Both devices are located in the tail of the plane to increase the chances of survival following a crash. Although earlier black boxes were in fact painted black， they are now painted bright orange to make them easier to locate in a plane’s wreckage.

A solid state flight data recorder （SSFDR） can store up to 25 hours of flight data. The main 4）components of an SSFDR are an interface and controller board （ICB）， power supply， crash survivable memory unit （CSMU） and an optional under water locator beacon （ULB）. The ICB is a single circuit board that controls the SSFDR and provides data processing capabilities. It enables front-end data conditioning， recording， and monitoring and ensures that up to 700 different parameters associated with an airplane’s operating conditions are recorded by the CSMU.

The CSMU of the FDR is often the only device that survives a plane crash and holds the secrets of what went wrong. The CSMU is designed to be resistant to shock， 5）temperature extremes， and pressure according to the 6）EUROCAE ED-112 standard for Minimum Operational Performance Specifications for Crash Protected Airborne Recorder Systems. Even so， if investigators cannot find the FDR， it is of little use.

The ULB will send out a ping signal for at least 30 days that can be detected from up to two miles away. However， there have been several instances where the flight data recorders were never recovered， such as the ones from the Boeing 767s that hit the World Trade Center in New York on 9/11. This leaves many people wondering why， given all of our technological advancements， flight data is not uploaded in real-time.

In fact， all airplanes do have an Aircraft Communications Addressing and Reporting System （ACARS） that sends critical information about the airplane to the ground in real-time. However， only basic information is sent such as whether or not the doors are closed and the plane’s altitude and location. Plus， ACARS data is typically only sent during events such as takeoff and landing and not continuously during the entire flight. The amount of data recorded by the FDR during the entire flight that would need to be uploaded in real-time would be immense. While I think we have the technology required to support the necessary 7）bandwidth and storage capacity， the real question is at what expense？

It is well known that traveling by plane is far safer than driving in a car. According to the National Safety Council （NSC）， the lives lost on US roadways each year 8）are equivalent to the lives that would be lost from a 100-passenger jet crashing every day of the year. Is the extra expense of having real-time data transferred from a plane in flight really worth it？ I am sure that if we asked that question to those waiting to find out the fate of their loved ones on Malaysia Airlines flight MH370， they would say that it is.

Unfortunate events such as these are prompting people to rethink airplane communications and tracking. For example， a Canadian company named Flyht has developed a portable satellite communications device， based on a global positioning system （GPS）， to monitor and stream critical data in realtime from anywhere in the world. Makes sense to me since GPS signals are already found in many devices that we use everyday such as our cell phones and cars. Do you think that with continued improvements to GPS systems， they will finally devise a viable alternative to the infamous black box？ Only time will tell.

馬來西亞航空公司失聯的MH370航班——在3月8日失蹤的一架波音777飛機，在這段時日里成為許多人心中的疑團。一架飛機怎會就這么在空中消失了？尋回飛行數據記錄儀——也就是大家所熟知的飛機黑匣子（盡管其實它是橙色的），或許會是解開這個謎題的唯一辦法。這讓我不禁產生疑問：一個裝有電子線路板的黑匣子究竟如何能在毀滅性的墜機情況中保持完好無損呢？真相是：電子部件很可能會被毀壞，但記錄的數據卻可以被恢復。

其實，飛機上裝有兩個數據記錄裝置：一個是駕駛艙話音記錄儀，用來記錄駕駛艙里的對話，如飛機師與空中交通管制站之間的通信，而另一個就是飛行數據記錄儀，用來記錄飛機在飛行中數以百計的不同參數。兩個儀器都安裝在飛機的尾部以提高在飛機墜毀時被完整保留下來的幾率。盡管早期的黑匣子的確是被漆成黑色的，但現在被漆成了鮮艷的橙色，目的是使其在飛機殘骸中更容易被發現。

一個固態飛行數據記錄儀能夠記錄25個小時的飛行數據。其主要的部件包括有：一個接口與控制板、供電電源、耐沖擊記憶單元，以及可選配的水下定位信標。接口與控制板是一個單一電路板，負責控制固態飛行數據記錄儀以及提供數據處理功能。它能夠進行前端數據的處理、記錄和監控，并確保多達700項與飛機運行狀況有關的不同數據被記錄到耐沖擊記憶單元上。

飛行記錄儀中的耐沖擊記憶單元通常會是飛機墜毀事故中唯一幸存的裝置，而且它保存著事故原因的秘密真相。……