The crash occurred over the Potomac River near Reagan National Airport, killing 67 people.

墜機發生在雷根國家機場附近的波托馬克河上空，造成 67 人死亡。

It's one of the most restricted airspaces in the country, but this particular area has long-worried pilots like retired Army officer Darrell Feller.

這裡是全國限制最多的空域之一，但這個特殊區域卻讓像退休陸軍軍官達雷爾-費勒（Darrell Feller）這樣的飛行員擔心了很久。

That's probably the most dangerous spot on all those routes in D.C.

這可能是華盛頓特區所有這些路線上最危險的地方。

So here's everything we know about why that area is so precarious.

下面是我們所知道的關於該地區為何如此岌岌可危的一切。

The 33-mile radius around Washington, D.C. is considered a special flight rules area.

華盛頓特區周圍半徑 33 英里的區域被視為特殊飛行規則區域。

Pilots have to have advanced clearance from the FAA to fly here, and aircraft must have altitude-encoding transponders, among other things.

飛行員必須事先獲得美國聯邦航空局的許可才能在這裡飛行，飛機必須安裝高度編碼轉發器等。

Within that, there's a 17-mile flight-restricted zone around Reagan Airport, with even stricter rules.

在這一範圍內，雷根機場周圍有一個 17 英里的飛行禁區，規定更為嚴格。

And then there are prohibited areas around the White House, National Mall, and the Vice President's residence.

此外，白宮、國家廣場和副總統官邸周圍也有禁區。

But even with the restrictions, it's still one of the most congested airspaces in the country, with civilian, military, police, and other government aircraft constantly operating.

但即使有了這些限制，這裡仍然是全國最擁擠的空域之一，民用、軍用、警用和其他政府飛機不斷在此運行。

To help manage this, D.C. has designated helicopter corridors, as well as altitude restrictions, to keep everyone safe.

為幫助管理這一問題，華盛頓特區指定了直升機通道，並對飛行高度進行了限制，以確保所有人的安全。

So what happened during the crash?

墜機時發生了什麼？

Flight data shows the Black Hawk helicopter flying south down a helicopter corridor over the Potomac River.

飛行數據顯示，黑鷹直升機沿著波托馬克河上空的直升機走廊向南飛行。

Military officials say the pilots were experienced and were conducting an annual night training mission known as a checkride.

軍方官員說，這些飛行員經驗豐富，當時正在執行年度夜間訓練任務，也就是所謂的檢閱。

Meanwhile, American Airlines Flight 5342 was traveling north toward Reagan National.

與此同時，美國航空公司 5342 號班機正向北飛往裡根國家機場。

It was originally supposed to land on Runway 1, with a flight path that goes up the river.

它原本應該降落在 1 號跑道上，飛行路線沿河而上。

But at approximately 8.42 p.m., minutes before landing, the jet was told to use a different, shorter runway.

但在晚上 8 點 42 分左右，也就是著陸前幾分鐘，飛機被告知使用另一條更短的跑道。

Runway changes aren't unusual, but it meant the plane had to bow right before turning sharply left and cutting across the helicopter corridor, a move that pilots say makes the jet hard for helicopters to see, especially at a low altitude.

跑道變化並不罕見，但這意味著飛機必須先向右急轉，然後再向左急轉，穿過直升機通道，飛行員們說，這一動作會讓直升機難以看到噴氣式飛機，尤其是在低空。

And you can't see them if they're moving toward you, away from you, or you can't see them at all.

如果它們朝你走來、離你而去，你就看不到它們，或者你根本看不到它們。

There are also questions about staffing of air traffic control that night and whether more people should have been working.

還有人質疑當晚空中交通管制的人員配備，以及是否應該有更多的人在工作。

Another potential problem was altitude.

另一個潛在問題是海拔高度。

Helicopters are supposed to fly below 200 feet in this part of the corridor.

直升機在這段走廊的飛行高度應低於 200 英尺。

But flight data shows the helicopter may have risen above 300 feet as the airplane was descending from 400 feet.

但飛行數據顯示，當飛機從 400 英尺高度下降時，直升機可能已上升到 300 英尺以上。

Officials say data from the aircraft's recording device still needs to be investigated to confirm.

官方稱，飛機記錄裝置的數據仍需調查確認。

But Feller says even if altitude was a factor, something else likely went wrong before that.

但費勒說，即使海拔高度是一個因素，在此之前也可能出了其他問題。

A professional Army aviator is not going to fly within 100 feet of a passenger jet.

一名專業的陸軍飛行員是不會在距離客機 100 英尺的範圍內飛行的。

He's just not going to do that.

他不會那麼做的。

I would suspect that he didn't see the jet.

我懷疑他沒有看到飛機。

During a press briefing, Defense Secretary Pete Hegseth said this.

在新聞發佈會上，國防部長 Pete Hegseth 這樣說道。

There was some sort of an elevation issue that we have immediately begun investigating at the DOD and Army level.

我們已立即開始在國防部和陸軍一級調查某種升降問題。

Army CID is on the ground investigating.

陸軍刑事調查局正在當地進行調查。

Top-tier aviation assets inside the DOD are investigating, sir, to get to the bottom of it so that it does not happen again because it's absolutely unacceptable.

國防部內部的頂級航空資產正在進行調查，先生，以查明真相，使其不再發生，因為這是絕對不能接受的。

After the crash, the FAA announced it would restrict helicopter traffic in the area where the Black Hawk was traveling.

墜機事件發生後，美國聯邦航空局宣佈將限制 "黑鷹 "飛行區域的直升機交通。

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欲瞭解更多聯合國視頻，請訪問 www.un.org