1
00:00:03,241 --> 00:00:07,413
639 pieces of wreckage
are recovered from the scene.
2
00:00:09,000 --> 00:00:11,206
Six hundred
and thirty-nine pieces
3
00:00:11,310 --> 00:00:15,103
that only deepen the mystery
of a deadly plane crash.
4
00:00:15,206 --> 00:00:17,931
All right,
a little bit more
to the right. There!
5
00:00:18,034 --> 00:00:23,965
But when investigators
bring up the 648th piece
of China Airlines Flight 611,
6
00:00:24,068 --> 00:00:25,965
they get their answer.
7
00:00:26,068 --> 00:00:29,137
There was definitely
a eureka moment on the dock.
8
00:00:29,241 --> 00:00:32,310
It would
be scrutinized more closely
than any other piece of debris.
9
00:00:34,137 --> 00:00:36,206
On this single piece
of wreckage,
10
00:00:36,310 --> 00:00:39,586
investigators would find
the one clue
that would tell them
11
00:00:39,689 --> 00:00:45,344
why a modern jetliner
with 225 people on board
shattered in mid-air.
12
00:00:56,586 --> 00:00:58,068
Mayday! Mayday!
13
00:01:22,655 --> 00:01:23,517
Thirty feet.
14
00:01:25,137 --> 00:01:26,379
Speed is low, sir, watch it.
15
00:01:28,655 --> 00:01:30,344
Did you feel that?
16
00:01:55,689 --> 00:01:57,931
May the 25th, 2002.
17
00:02:04,965 --> 00:02:07,034
Gears up.
18
00:02:07,137 --> 00:02:11,862
A China Airlines 747
lifts off from Taiwan's capital,
Taipei.
19
00:02:14,241 --> 00:02:20,000
Taipei approach,
Dynasty 611 airborne
passing 1,600.
20
00:02:20,103 --> 00:02:23,034
Dynasty 611,
Taipei approach radar
21
00:02:23,137 --> 00:02:26,103
contact climb
and maintain
flight level 260.
22
00:02:28,034 --> 00:02:30,517
Two, six, zero.
Dynasty 611.
23
00:02:31,655 --> 00:02:33,586
Autopilot B, engage.
24
00:02:38,103 --> 00:02:40,724
China Airlines
is Taiwan's national airline.
25
00:02:42,344 --> 00:02:46,034
There are 225 people on board
Flight 611.
26
00:02:46,931 --> 00:02:49,103
Today's flight is a short one.
27
00:02:49,206 --> 00:02:52,620
One hour and 40 minutes
across the Taiwan Strait
to Hong Kong.
28
00:02:56,482 --> 00:02:59,241
This route is one of the most
widely-traveled on the planet.
29
00:03:00,724 --> 00:03:02,172
It makes so much money,
30
00:03:02,275 --> 00:03:04,965
it's called The Golden Route.
31
00:03:05,068 --> 00:03:06,931
Ladies and gentlemen,
the fasten seatbelt sign
32
00:03:07,034 --> 00:03:08,275
has been turned off.
33
00:03:08,379 --> 00:03:10,275
For your safety,
we do recommend
that you keep
34
00:03:10,379 --> 00:03:12,655
your seatbelt fastened
at all times while seated.
35
00:03:19,793 --> 00:03:21,482
Minutes after taking off,
36
00:03:21,586 --> 00:03:25,000
Flight 611 climbed steadily
above the Taiwan Strait.
37
00:03:28,310 --> 00:03:30,655
The plane's autopilot
controls the ascent.
38
00:03:34,827 --> 00:03:37,172
And, then, 20 minutes
after taking off,
39
00:03:38,413 --> 00:03:41,793
at an altitude
of almost 35,000 feet...
40
00:03:49,172 --> 00:03:53,275
At Taipei Area Control,
the flight vanishes from radar.
41
00:03:53,379 --> 00:03:57,724
Dynasty 611, Taipei.
Dynasty 611, Taipei.
42
00:03:59,448 --> 00:04:01,068
I've got a plane off radar.
43
00:04:01,172 --> 00:04:03,586
China Airlines 611.
44
00:04:03,689 --> 00:04:07,827
It's last known
return was East 119
decimal 67,
45
00:04:07,931 --> 00:04:09,862
North 23,
decimal 98.
46
00:04:13,448 --> 00:04:17,206
Taiwanese authorities
quickly launch one of
the largest rescue missions
47
00:04:17,310 --> 00:04:19,172
in that country's
aviation history.
48
00:04:35,655 --> 00:04:38,241
I gave
a clear order that the priority
49
00:04:38,344 --> 00:04:41,241
would be searching
for whoever was still alive.
50
00:04:41,344 --> 00:04:45,103
Then bodies, and then,
only then, wreckage.
51
00:04:49,724 --> 00:04:51,689
More than
1,000 people take part.
52
00:04:53,965 --> 00:04:58,172
Fishing boats, the Coast Guard,
and Taiwan's military
race out to sea.
53
00:05:00,724 --> 00:05:04,310
Flight 611 was 55 kilometers
from the Taiwanese shore,
54
00:05:04,413 --> 00:05:06,965
just north of the Penghu Islands
when it disappeared.
55
00:05:13,068 --> 00:05:16,034
Rescuers find debris
floating in the Taiwan Strait.
56
00:05:17,517 --> 00:05:20,379
The first thing
we saw
57
00:05:20,482 --> 00:05:22,068
was a great amount
of wreckage,
58
00:05:22,172 --> 00:05:26,379
including landing gear wheels,
napkins, knives, and forks.
59
00:05:29,586 --> 00:05:33,827
Wreckage from the plane
is spread far and wide.
60
00:05:33,931 --> 00:05:38,724
Some items are found on land
more than 100 kilometers
away in central Taiwan.
61
00:05:41,172 --> 00:05:45,379
As the rescue effort continues,
Taiwan's Aviation Safety Council
62
00:05:45,482 --> 00:05:49,241
begins its investigation
into the crash
of the 22-year-old plane.
63
00:05:49,344 --> 00:05:54,965
747-200,
delivered August 2nd, 1979.
64
00:05:55,068 --> 00:05:57,793
Kay Yong
is the managing director
of the ASC.
65
00:05:58,896 --> 00:06:00,862
He'll be leading
the investigation.
66
00:06:00,965 --> 00:06:05,103
We're setting up
a command post
on Penghu Island. Let's go.
67
00:06:07,310 --> 00:06:11,586
China Airlines have had
a very, very poor
safety record.
68
00:06:11,689 --> 00:06:16,344
As a matter of fact,
it was considered
one of the worst in the world.
69
00:06:18,275 --> 00:06:21,103
Typically, it had, like,
one major accident
every four years.
70
00:06:23,137 --> 00:06:27,862
This particular investigation
was, by far,
the most difficult one.
71
00:06:27,965 --> 00:06:31,862
And one of the reasons why
was it's...
it's in the ocean floor.
72
00:06:35,413 --> 00:06:37,931
The search
for survivors goes on
around the clock.
73
00:06:46,758 --> 00:06:49,344
There were 225 people
on the airplane.
74
00:06:54,206 --> 00:06:55,482
Nobody is found alive.
75
00:07:06,931 --> 00:07:10,758
The bodies are taken
to the Penghu Islands
to be identified and examined.
76
00:07:22,275 --> 00:07:25,758
Since the accident involved
an American-made plane,
77
00:07:25,862 --> 00:07:28,793
the NTSB
joins the investigation.
78
00:07:28,896 --> 00:07:31,655
A team of investigators
is dispatched to Taiwan,
79
00:07:34,413 --> 00:07:37,413
They'll be led by John DeLisi
in Washington.
80
00:07:37,517 --> 00:07:40,758
We have a very good
working relationship
with the ASC,
81
00:07:40,862 --> 00:07:43,862
The Aviation Safety Council,
of Taiwan.
82
00:07:43,965 --> 00:07:46,551
So we knew that
they would ask for
83
00:07:46,655 --> 00:07:49,724
and welcome our assistance
in the investigation.
84
00:07:52,965 --> 00:07:54,206
Wreckage that's found floating
85
00:07:54,310 --> 00:07:56,172
is also brought
to the Penghu Islands.
86
00:07:58,689 --> 00:08:02,862
Investigators need to know
how one of the world's
most successful planes,
87
00:08:02,965 --> 00:08:06,620
on one of the world's
most-traveled routes,
simply fell out of the sky.
88
00:08:08,896 --> 00:08:12,896
Well, Boeing 747
is the world's most popular
jumbo jet,
89
00:08:13,000 --> 00:08:19,724
and it's flown
millions of people,
probably billions of miles.
90
00:08:19,827 --> 00:08:21,965
So it...
We were very concerned.
91
00:08:25,379 --> 00:08:28,448
Good morning. I'm anxious
to see what you have.
92
00:08:28,551 --> 00:08:30,758
Sophisticated ground based-radar
93
00:08:30,862 --> 00:08:34,655
tracked Flight 611
throughout its short journey.
94
00:08:34,758 --> 00:08:38,275
It should provide investigators
with a much clearer picture
of the flight
95
00:08:38,379 --> 00:08:41,103
than the radar
at Air Traffic Control.
96
00:08:41,206 --> 00:08:44,827
Kay Yong gets the first
major clue in this case.
97
00:08:44,931 --> 00:08:49,448
The radar tracked the plane
as it climbed on course
to 35,000 feet.
98
00:08:49,551 --> 00:08:52,758
Then, suddenly,
Flight 611's signals
split apart.
99
00:08:53,689 --> 00:08:55,034
The break up
is quite graphic.
100
00:08:56,551 --> 00:08:59,586
Right when the event happened,
it appeared as if there were
101
00:08:59,689 --> 00:09:05,172
three or four sizable pieces
of wreckage that were getting
radar returns
102
00:09:05,275 --> 00:09:09,586
that then began to drift
and scatter as they fell
to the earth.
103
00:09:09,689 --> 00:09:13,310
So that told us
that the airplane
broke up in flight.
104
00:09:18,551 --> 00:09:20,655
Investigators now
must turn their attention
105
00:09:20,758 --> 00:09:22,689
to finding out what caused
that breakup.
106
00:09:24,103 --> 00:09:26,034
There's all kinds
of theories about,
107
00:09:26,137 --> 00:09:29,275
you know,
what seems to be happening
on that particular aircraft.
108
00:09:29,379 --> 00:09:31,310
We knew that something
massive had happened,
109
00:09:32,344 --> 00:09:35,965
happened suddenly
without warning.
110
00:09:36,068 --> 00:09:39,724
It doesn't take long
for the media to consider
a sinister possibility,
111
00:09:41,379 --> 00:09:43,586
that Flight 611 was shot down.
112
00:09:48,379 --> 00:09:52,034
- China and Taiwan
have a combative relationship.
-
113
00:09:53,517 --> 00:09:56,413
China has fired missiles
towards Taiwan in the past.
114
00:09:58,206 --> 00:10:01,931
There's suspicion in the media
that China shot down
Flight 611.
115
00:10:03,689 --> 00:10:06,896
There were a lot of theories
about, you know, the...
116
00:10:07,000 --> 00:10:11,172
It was shooting down
by enemy fire.
117
00:10:11,275 --> 00:10:14,413
Only eight months earlier,
a Siberia Airlines flight
118
00:10:14,517 --> 00:10:19,551
with 78 people on board
was shot down
over the Black Sea.
119
00:10:19,655 --> 00:10:24,172
It was accidentally hit
by a missile fired from Ukraine
during a training exercise.
120
00:10:28,068 --> 00:10:30,862
On the day
of the China Airlines crash,
121
00:10:30,965 --> 00:10:34,275
China was conducting
military exercises
in the Taiwan Strait.
122
00:10:36,206 --> 00:10:40,655
But officials there insist
no missile was launched
towards Flight 611.
123
00:10:43,965 --> 00:10:45,758
None of the wreckage
recovered so far
124
00:10:45,862 --> 00:10:49,827
has any of the telltale signs
of being hit.
125
00:10:49,931 --> 00:10:55,482
And there's no evidence on radar
that there was ever a missile
heading for Flight 611.
126
00:10:55,586 --> 00:10:57,137
Once the evidence
began to come in,
127
00:10:57,241 --> 00:10:59,827
it very quickly ruled out
a missile,
128
00:10:59,931 --> 00:11:02,586
much the same way
that it ruled out
it being a mid-air collision.
129
00:11:02,689 --> 00:11:06,448
There were no other objects
in the air near the airplane.
130
00:11:08,310 --> 00:11:11,034
Few things
would cause a plane
to break up in mid-air.
131
00:11:12,689 --> 00:11:14,517
One of the big ones
is a bomb.
132
00:11:16,862 --> 00:11:19,275
Medical examiners
check the bodies
that have been recovered
133
00:11:19,379 --> 00:11:20,931
for burn marks
and shrapnel.
134
00:11:23,241 --> 00:11:24,793
They find none.
135
00:11:29,241 --> 00:11:33,379
The plane's metal skin
would be torn and curled
in a very particular way
136
00:11:33,482 --> 00:11:35,413
if there had been
a bomb on board.
137
00:11:35,517 --> 00:11:38,724
Investigators find
no such damage
on any of the pieces.
138
00:11:40,689 --> 00:11:43,724
But to rule out a bomb,
they'll have to find
more wreckage.
139
00:11:45,689 --> 00:11:49,448
I think that'll be it
for floating wreckage.
140
00:11:49,551 --> 00:11:52,862
The team from the NTSB
arrives in Taiwan.
141
00:11:52,965 --> 00:11:55,620
Good morning.
I'm Clint Crookshanks
from the NTSB.
142
00:11:55,724 --> 00:11:59,689
Good to see you, gentlemen.
I'm afraid we still
don't have much.
143
00:11:59,793 --> 00:12:04,344
Clint Crookshanks
is a structural engineer
who knows the 747 intimately.
144
00:12:05,551 --> 00:12:07,137
I didn't have
any preconceived notions.
145
00:12:07,241 --> 00:12:11,586
This was
my first major accident
working for the NTSB.
146
00:12:11,689 --> 00:12:14,482
We are not getting much
from the floating debris.
147
00:12:14,586 --> 00:12:17,344
In flight break-up,
that's all we know.
148
00:12:20,724 --> 00:12:25,275
Taiwan's Civil
Aeronautics Authority
doesn't take any chances.
149
00:12:25,379 --> 00:12:30,655
They ground all
of China Airlines'
747-200 series planes
150
00:12:30,758 --> 00:12:33,724
until they can be inspected
for mechanical flaws.
151
00:12:36,413 --> 00:12:40,724
This puts added pressure
on investigators
to find out what happened.
152
00:12:40,827 --> 00:12:42,379
Thank you for bringing these.
153
00:12:44,068 --> 00:12:47,724
To the NTSB,
this accident seems
to have a lot in common
154
00:12:47,827 --> 00:12:50,206
with one of the world's
most-studied plane crashes.
155
00:12:53,241 --> 00:12:56,896
That of TWA Flight 800
six years earlier.
156
00:12:59,758 --> 00:13:03,551
Like the China Airlines flight,
it broke into pieces
while still climbing.
157
00:13:06,103 --> 00:13:07,965
That plane crashed
into the Atlantic
158
00:13:08,068 --> 00:13:11,344
shortly after taking off
from New York.
159
00:13:11,448 --> 00:13:15,896
TWA Flight 800
was the biggest investigation
the NTSB has ever done.
160
00:13:16,000 --> 00:13:17,275
Lasted about four years.
161
00:13:19,517 --> 00:13:23,793
The painstaking
investigation uncovered
a design flaw with the 747.
162
00:13:25,206 --> 00:13:27,482
Wiring near one of the plane's
fuel tanks
163
00:13:27,586 --> 00:13:30,137
could spark and ignite the fuel
in the tank.
164
00:13:30,241 --> 00:13:32,000
Investigators conclude
165
00:13:32,103 --> 00:13:34,758
that's what likely
caused the crash.
166
00:13:34,862 --> 00:13:38,344
Investigators are struck
by similarities
between the two flights.
167
00:13:39,482 --> 00:13:42,344
Both were 747s.
168
00:13:42,448 --> 00:13:45,344
Both disintegrated
without warning
while still climbing.
169
00:13:47,172 --> 00:13:49,379
Both flights took off
in very hot weather.
170
00:13:51,862 --> 00:13:54,689
The heat may have caused
Flight 800 to explode.
171
00:13:56,758 --> 00:14:00,620
That plane sat on the tarmac
with its air-conditioning
running.
172
00:14:00,724 --> 00:14:05,103
Investigators believe hot air
from the air conditioner
overheated the plane's fuel.
173
00:14:09,034 --> 00:14:13,275
The early evidence is pointing
to a repeat of TWA Flight 800.
174
00:14:17,068 --> 00:14:19,000
So it looks really
very, very similar.
175
00:14:19,103 --> 00:14:23,275
So, therefore, the...
our immediate focus
176
00:14:23,379 --> 00:14:25,379
was, essentially,
the central fuel tank.
177
00:14:30,413 --> 00:14:33,413
Three weeks
after the crash,
the Jan Steen,
178
00:14:33,517 --> 00:14:37,689
a sophisticated salvage vessel,
arrives in the Taiwan Strait.
179
00:14:37,793 --> 00:14:41,103
It's equipped with divers,
a diving chamber,
180
00:14:41,206 --> 00:14:45,862
and a remote-operated submarine
complete with sonar
and video cameras.
181
00:14:45,965 --> 00:14:49,758
The NTSB were tasked with
manning the recovery vessel
182
00:14:49,862 --> 00:14:52,689
and watching video screens
from the ROV.
183
00:14:56,103 --> 00:14:57,724
Using sonar,
184
00:14:57,827 --> 00:15:01,413
investigators have located
the wreckage of Flight 611
deep underwater.
185
00:15:05,000 --> 00:15:05,827
All right,
to the right a bit.
186
00:15:08,275 --> 00:15:12,551
Clint Crookshanks
knows all the pieces
that make up a 747.
187
00:15:12,655 --> 00:15:15,724
But he's never seen them
like this.
188
00:15:15,827 --> 00:15:19,793
It was really quite a shock
when I first saw pieces
on the floor of the ocean.
189
00:15:21,379 --> 00:15:24,000
With only the lighting
of the ROV to guide you,
190
00:15:24,103 --> 00:15:27,206
you would notice something
that looked like
an airplane part.
191
00:15:27,310 --> 00:15:31,172
The ROV would then circle around
the part, looking at it
from all angles.
192
00:15:32,862 --> 00:15:35,068
Crookshanks' job
is to help the Taiwanese
193
00:15:35,172 --> 00:15:38,172
identify specific airplane parts
among the wreckage.
194
00:15:39,206 --> 00:15:42,275
I think it takes
a different kind of mind
195
00:15:42,379 --> 00:15:44,344
to be able to look
at a mangled part
196
00:15:44,448 --> 00:15:46,551
and kind of straighten it out
in your head
197
00:15:46,655 --> 00:15:48,965
to really determine
where it comes from
on the airplane.
198
00:15:50,655 --> 00:15:51,965
All right, a little bit more
to the right.
199
00:15:52,827 --> 00:15:54,103
All right, go back.
200
00:15:56,793 --> 00:15:59,620
There! Okay, that's definitely
a piece of wing. Let's mark it.
201
00:16:01,034 --> 00:16:02,655
Once a piece
is identified,
202
00:16:02,758 --> 00:16:04,931
its GPS coordinates
get recorded.
203
00:16:06,758 --> 00:16:08,965
The GPS mapping
tells investigators
204
00:16:09,068 --> 00:16:14,068
that the debris is spread out
over 325 square kilometers.
205
00:16:14,172 --> 00:16:17,137
It will be difficult
to track down
specific pieces of the plane.
206
00:16:19,482 --> 00:16:22,586
Twenty-five days
after the crash
of Flight 611,
207
00:16:22,689 --> 00:16:26,275
the plane's two black boxes
have been found.
208
00:16:26,379 --> 00:16:29,448
One contains voice recordings
of conversations in the cockpit.
209
00:16:31,137 --> 00:16:33,827
The other, data from
the plane's flight computer.
210
00:16:36,068 --> 00:16:38,793
Either could hold the clues
that will reveal what happened
211
00:16:38,896 --> 00:16:40,379
during the final minutes
of the flight.
212
00:16:42,931 --> 00:16:46,344
If the answer is on the tape,
investigators may not have to
bring up
213
00:16:46,448 --> 00:16:48,241
more wreckage
to the surface.
214
00:16:50,413 --> 00:16:51,655
The data is critical.
215
00:16:55,000 --> 00:16:57,241
Everybody ready?
216
00:16:57,344 --> 00:17:00,172
Investigators begin
with the plane's cockpit
voice recorder.
217
00:17:03,379 --> 00:17:05,655
They hope that the pilots
will have said something
to each other
218
00:17:05,758 --> 00:17:07,275
about an emergency on board.
219
00:17:09,241 --> 00:17:11,482
Welcome aboard China Airlines.
220
00:17:11,586 --> 00:17:14,724
The recording begins
about 10 minutes
before the plane took off.
221
00:17:18,793 --> 00:17:22,034
- Twenty.
- Preparations
for the flight sound normal.
222
00:17:22,137 --> 00:17:27,172
- Okay, after start checklist.
- After start, anti-ice.
223
00:17:27,275 --> 00:17:28,862
The crew
checks all their systems
224
00:17:28,965 --> 00:17:30,758
and runs through
standard checklists.
225
00:17:31,379 --> 00:17:33,172
Off. Off.
226
00:17:33,275 --> 00:17:35,655
It was a very,
very experienced crew.
227
00:17:35,758 --> 00:17:39,689
Both the captain and the fli...
and the first officers
were quite seasoned.
228
00:17:41,172 --> 00:17:44,413
Dynasty 611, runway 06,
229
00:17:44,517 --> 00:17:47,586
wind 050
at nine are cleared
for take-off.
230
00:17:49,724 --> 00:17:51,586
Cleared for takeoff.
Dynasty 611.
231
00:17:52,827 --> 00:17:54,172
Take off.
232
00:17:59,068 --> 00:18:00,586
- 80.
- Check.
233
00:18:01,655 --> 00:18:02,620
Vee one.
234
00:18:05,551 --> 00:18:06,448
Rotate.
235
00:18:14,379 --> 00:18:17,448
- CO-PILOT: [ON RADIO] Flap five.
One-one green.
236
00:18:18,206 --> 00:18:20,034
CO-PILOT: Okay, flap up.
237
00:18:20,137 --> 00:18:23,931
Investigators listen
to more than conversations.
238
00:18:24,034 --> 00:18:28,275
They also want to hear
if the plane itself
was making any unusual sounds.
239
00:18:28,379 --> 00:18:33,103
Noises on the cockpit
voice recorder can either
be audible spoken words
240
00:18:33,206 --> 00:18:35,448
that are recorded
by a microphone,
241
00:18:35,551 --> 00:18:40,344
or they can be
structural discrepancies
that are picked up
242
00:18:40,448 --> 00:18:41,413
by the microphone.
243
00:18:43,379 --> 00:18:46,482
If anything, though,
this cockpit is unusually quiet.
244
00:18:46,586 --> 00:18:50,689
Uni Air 608,
reduce speed...
245
00:18:50,793 --> 00:18:52,413
The captain
seems relaxed.
246
00:18:55,448 --> 00:18:57,620
The microphones
pick up the sound
of controllers
247
00:18:57,724 --> 00:18:59,275
talking to other planes.
248
00:18:59,379 --> 00:19:04,137
Trans Asia 536
fly heading 050.
249
00:19:05,862 --> 00:19:09,206
In the moments
before the disaster,
nothing seems wrong.
250
00:19:10,517 --> 00:19:12,344
There are no unusual sounds.
251
00:19:12,448 --> 00:19:16,413
Now descend
and maintain 250.
252
00:19:16,517 --> 00:19:20,034
The final words
spoken in the cockpit
are from Captain Yi Ching-Fung.
253
00:19:20,862 --> 00:19:22,275
Two thousand.
254
00:19:22,379 --> 00:19:24,689
He calls out
the distance
to their cruising altitude.
255
00:19:25,827 --> 00:19:27,793
That's followed
by the sound of a chime...
256
00:19:29,310 --> 00:19:32,344
...alerting the crew
that they are
nearing 35,000 feet.
257
00:19:35,206 --> 00:19:39,068
And then the cockpit microphone
picks up the sound of the plane
breaking apart.
258
00:19:42,206 --> 00:19:45,689
Half a second later,
the recording stops.
259
00:19:45,793 --> 00:19:49,137
The cockpit voice recorder
indicated that the...
260
00:19:49,241 --> 00:19:53,103
the conversation
of the cockpit crew
were totally normal,
261
00:19:53,206 --> 00:19:55,517
and all of a sudden, just...
just dying.
262
00:19:55,620 --> 00:19:57,379
The recorders told us
that something happened,
263
00:19:57,482 --> 00:20:00,862
but it wasn't enough to tell us
exactly what it was yet.
264
00:20:00,965 --> 00:20:06,172
Many things had been ruled out
by then, but we didn't have
the golden nugget.
265
00:20:06,275 --> 00:20:08,103
We didn't have
the real piece of evidence
266
00:20:08,206 --> 00:20:11,965
that told us what initiated
the breakup of the 747.
267
00:20:13,551 --> 00:20:16,137
After the disappointment
of the voice recorder,
268
00:20:16,241 --> 00:20:19,551
studying the wreckage
becomes the only option
for investigators.
269
00:20:24,000 --> 00:20:26,103
They focus their efforts
on items that can either
270
00:20:26,206 --> 00:20:29,379
prove or disprove
the link to TWA Flight 800.
271
00:20:32,896 --> 00:20:37,620
So we play a lot of focus
on the wreckage observation,
272
00:20:37,724 --> 00:20:40,344
examination of the center
fuel tank.
273
00:20:40,448 --> 00:20:43,103
On July the 12th,
48 days after the crash...
274
00:20:43,965 --> 00:20:45,517
Okay, whoa, whoa.
275
00:20:45,620 --> 00:20:48,000
Little to the left, please.
276
00:20:48,103 --> 00:20:49,310
Success.
277
00:20:50,379 --> 00:20:52,379
All right.
278
00:20:52,482 --> 00:20:55,206
That's definitely
the central fuel tank.
279
00:20:55,310 --> 00:20:57,275
Okay, let's mark that.
Let's bring that up.
280
00:21:05,172 --> 00:21:08,172
The tank joins
the sea of wreckage
piling up at the pier.
281
00:21:10,551 --> 00:21:14,000
Investigators study it closely
for any evidence
that it exploded.
282
00:21:15,931 --> 00:21:19,758
If it did explode
like the TWA tank,
it would be curled and twisted.
283
00:21:23,310 --> 00:21:25,586
And the metal
would be bent outwards.
284
00:21:28,896 --> 00:21:30,413
But this fuel tank
is different.
285
00:21:31,862 --> 00:21:35,931
And we found
the central field tank
was relatively intact.
286
00:21:37,344 --> 00:21:39,586
And it's crumpled inwards.
287
00:21:39,689 --> 00:21:43,586
Unlike the tank
from the TWA flight,
there's no soot.
288
00:21:43,689 --> 00:21:46,241
There would be
if the jet fuel inside
had ignited.
289
00:21:48,172 --> 00:21:50,206
So, at that time,
we pretty much ruled out
290
00:21:50,310 --> 00:21:52,137
it was the cause
of the center fuel tank.
291
00:21:54,931 --> 00:21:58,206
The wreckage
recovered so far
has also forced investigators
292
00:21:58,310 --> 00:22:00,206
to abandon another theory,
293
00:22:00,310 --> 00:22:02,275
that a bomb brought down
the plane.
294
00:22:04,517 --> 00:22:07,620
None of the wreckage
showed any evidence
of sooting,
295
00:22:07,724 --> 00:22:10,758
any kind of explosive damage.
296
00:22:10,862 --> 00:22:15,689
The China Airlines
crash was neither a repeat
of TWA Flight 800,
297
00:22:15,793 --> 00:22:18,137
nor a deliberate bombing.
298
00:22:18,241 --> 00:22:20,068
Investigators are running
out of leads.
299
00:22:23,103 --> 00:22:25,827
As more wreckage
is identified and recovered,
300
00:22:25,931 --> 00:22:28,000
investigators find
an intriguing clue.
301
00:22:30,000 --> 00:22:34,241
It's discovered
when they examine a series
of small vents from Flight 611.
302
00:22:39,137 --> 00:22:43,551
All commercial jetliners
have dozens of these vents
near the floor.
303
00:22:43,655 --> 00:22:45,482
They're essentially
pressure release valves.
304
00:22:46,862 --> 00:22:49,310
They're called dado panels,
305
00:22:49,413 --> 00:22:51,620
and there's only one reason
for them to open.
306
00:22:53,000 --> 00:22:55,206
If the cargo area
underneath the passengers
307
00:22:55,310 --> 00:22:58,517
were to suddenly decompress,
the pressurized air above
308
00:22:58,620 --> 00:23:00,482
would exert so much force
on the floor
309
00:23:00,586 --> 00:23:04,172
that it could collapse
and damage
vital fight controls.
310
00:23:04,275 --> 00:23:08,793
That's precisely what happened
to a Turkish Airlines flight
in 1974.
311
00:23:11,689 --> 00:23:15,310
The pilots couldn't
control their plane
after their cargo door blew out.
312
00:23:21,655 --> 00:23:23,206
We've lost it!
313
00:23:23,310 --> 00:23:25,689
If the floor
on that flight
hadn't collapsed,
314
00:23:25,793 --> 00:23:28,655
the pilots may have been
able to save the plane.
315
00:23:35,413 --> 00:23:38,172
After that accident,
the NTSB recommended
316
00:23:38,275 --> 00:23:41,172
that manufacturers
install many more relief vents
317
00:23:41,275 --> 00:23:43,827
between a passenger plane's
upper and lower levels.
318
00:23:45,551 --> 00:23:48,000
If there is decompression
in the cargo area,
319
00:23:48,103 --> 00:23:50,034
the dado panels
open automatically
320
00:23:50,137 --> 00:23:51,689
and release the pressure
on the floor.
321
00:23:54,413 --> 00:23:57,482
There were 65 dado panels
on the China Airlines flight.
322
00:23:58,793 --> 00:24:00,655
Nineteen of them
were recovered
from the ocean.
323
00:24:01,965 --> 00:24:04,172
Four recovered panels
were in the open position.
324
00:24:06,034 --> 00:24:08,000
It tells investigators
that there must have been
325
00:24:08,103 --> 00:24:10,413
a sudden loss of pressure
beneath the passenger cabin.
326
00:24:12,068 --> 00:24:13,724
But it doesn't tell them
what caused it.
327
00:24:17,344 --> 00:24:19,689
The dado panels
lead investigators closer
328
00:24:19,793 --> 00:24:22,344
to solving the mystery
of this crash.
329
00:24:22,448 --> 00:24:26,275
But it's just a small piece
of a much bigger puzzle.
330
00:24:26,379 --> 00:24:29,310
There are hundreds of pieces
of wreckage to be examined
for clues.
331
00:24:30,793 --> 00:24:33,344
Kay Yong now wonders
if a few of those pieces
332
00:24:33,448 --> 00:24:36,689
might be able to tell him
where the decompression
originated.
333
00:24:36,793 --> 00:24:40,482
I've been reading about
the trajectory analysis
you did on Flight 800.
334
00:24:41,482 --> 00:24:43,448
I'd like to try it.
335
00:24:43,551 --> 00:24:46,137
Ballistic trajectory analysis
is a technique
336
00:24:46,241 --> 00:24:51,103
that US investigators used
to figure out how TWA Flight 800
disintegrated.
337
00:24:53,758 --> 00:24:56,379
It's impossible to do
without specialized computers.
338
00:24:58,586 --> 00:25:02,000
We figured that,
because it disintegrated
in the mid-air,
339
00:25:02,103 --> 00:25:04,896
the ballistic analysis
from which they,
340
00:25:05,000 --> 00:25:11,000
NTSB, did in TWA 800
could be very, very useful
to us,
341
00:25:11,103 --> 00:25:15,413
to help us to analyze
the trajectory
of the flying debris.
342
00:25:15,517 --> 00:25:18,620
The analysis
is based on a simple fact.
343
00:25:18,724 --> 00:25:23,137
The pieces that came off
the plane first would be
the first to hit the water.
344
00:25:23,241 --> 00:25:26,448
If investigators can figure out
which pieces those were,
345
00:25:26,551 --> 00:25:27,931
they'll know
where the trouble began.
346
00:25:30,172 --> 00:25:32,724
Radar that had been tracking
the plane as it climbed
347
00:25:32,827 --> 00:25:35,620
also ended up tracking pieces
of debris as they fell.
348
00:25:38,344 --> 00:25:41,000
The salvage workers
have recorded
the precise location
349
00:25:41,103 --> 00:25:42,724
of those same pieces
of wreckage.
350
00:25:44,517 --> 00:25:48,862
Their logs could match
a specific piece
to its radar track.
351
00:25:48,965 --> 00:25:53,034
Investigators know
the wind speed
on the day of the crash,
352
00:25:53,137 --> 00:25:56,275
and they can obtain
precise information
about ocean currents.
353
00:25:58,241 --> 00:26:02,655
The last piece of the puzzle
comes from the plane's
flight data recorder.
354
00:26:02,758 --> 00:26:05,931
The plane's altitude, speed,
and direction at the time
of the break-up.
355
00:26:13,103 --> 00:26:14,724
As they're
brought to the dock,
356
00:26:14,827 --> 00:26:18,482
every single piece of wreckage
has been logged and numbered
for identification.
357
00:26:22,068 --> 00:26:23,793
Three-two-seven.
358
00:26:23,896 --> 00:26:27,689
Kay Yong
selects 18 pieces of wreckage
for the computer analysis.
359
00:26:30,206 --> 00:26:32,724
Some from the front,
some from the middle,
360
00:26:32,827 --> 00:26:34,482
and some
from the back of the plane.
361
00:26:35,793 --> 00:26:37,034
One-nine-nine.
362
00:26:39,655 --> 00:26:42,655
Along with
all the other data,
he'll feed information
363
00:26:42,758 --> 00:26:45,724
about each item's weight
and shape into the computer.
364
00:26:48,517 --> 00:26:50,379
Five-two-six.
365
00:26:50,482 --> 00:26:54,517
Based on where
the pieces fell, the computer
should be able to calculate
366
00:26:54,620 --> 00:26:57,689
which of those 18 pieces
was the first
to come off the plane.
367
00:26:59,931 --> 00:27:03,310
Can we see when each one
of those items
separated from the aircraft?
368
00:27:08,862 --> 00:27:13,034
All of the data
paints a telling picture
of what happened at 35,000 feet.
369
00:27:15,103 --> 00:27:20,206
Kay Yong gets to see
how Flight 611 broke up
from beginning to end.
370
00:27:21,310 --> 00:27:24,310
The tail came off first.
371
00:27:24,413 --> 00:27:28,103
Along with
the dado panels,
it's a very important clue.
372
00:27:28,206 --> 00:27:34,034
So that pretty much indicating
that something happened
in the back of the aircraft,
373
00:27:34,137 --> 00:27:36,344
rather than something
happened in the forward part.
374
00:27:39,620 --> 00:27:43,172
Investigators are now keen to recover items
from the rear of the plane.
375
00:27:48,862 --> 00:27:52,827
Hundreds of pieces of wreckage
are piling up at the pier
on the Penghu Islands.
376
00:27:54,896 --> 00:27:57,620
The NTSB sends
metallurgist Frank Zakar
377
00:27:57,724 --> 00:27:59,758
to Taiwan to examine
the wreckage.
378
00:28:01,344 --> 00:28:06,896
I was walking along the yard
where the wreckage was placed,
379
00:28:07,000 --> 00:28:10,103
and, at that time,
I walked up to item 640.
380
00:28:11,517 --> 00:28:14,137
I noticed that there were some
peculiar areas of interest
381
00:28:14,241 --> 00:28:16,448
that I wanted
to look at
a little bit further.
382
00:28:18,413 --> 00:28:22,482
With this
battered piece of metal,
investigators have struck gold.
383
00:28:26,206 --> 00:28:27,482
There was definitely
a eureka moment on the dock
384
00:28:28,655 --> 00:28:31,655
that was, hey,
we might have something here.
385
00:28:34,793 --> 00:28:38,551
Hey, it's Frank.
I think we found
your golden nugget.
386
00:28:40,586 --> 00:28:43,689
Item number 640
would give investigators
387
00:28:43,793 --> 00:28:45,931
a revealing glimpse
into the past,
388
00:28:46,034 --> 00:28:50,137
and lead them to conclude
that the crash of Flight 611
389
00:28:50,241 --> 00:28:52,965
actually began
22 years earlier.
390
00:29:00,551 --> 00:29:03,034
Let's get as many pictures
as we can.
391
00:29:03,137 --> 00:29:06,758
The massive piece
of fuselage that has caught
Frank Zakar's attention
392
00:29:06,862 --> 00:29:09,448
is exactly what investigators
have been searching for.
393
00:29:12,379 --> 00:29:16,620
It includes a piece
of the belly, the side wall,
and the rear cargo door.
394
00:29:18,896 --> 00:29:21,034
It's from
the back of the plane,
395
00:29:21,137 --> 00:29:24,241
precisely where the analysis
told them the break-up
had begun.
396
00:29:25,517 --> 00:29:28,034
This piece of wreckage
was highly unusual.
397
00:29:28,137 --> 00:29:30,931
It wasn't what we were seeing
on all the other pieces.
398
00:29:31,034 --> 00:29:33,241
And it immediately
drew our attention,
399
00:29:33,344 --> 00:29:35,172
and drew the focus
of the investigation.
400
00:29:38,068 --> 00:29:40,241
The way
most of the metal is torn
401
00:29:40,344 --> 00:29:42,965
suggests it ripped apart
violently in mid-air.
402
00:29:44,827 --> 00:29:47,586
Aerodynamically,
as an airplane's
moving through the air,
403
00:29:47,689 --> 00:29:49,793
if it's... if it were
to break apart,
404
00:29:49,896 --> 00:29:54,103
just the force
of the incoming air
at over 500 miles per hour
405
00:29:54,206 --> 00:29:57,586
will just break up
perfectly good structure.
406
00:29:57,689 --> 00:29:59,758
That's what we call
an overload fracture.
407
00:29:59,862 --> 00:30:01,758
So most of the pieces
that came up early
408
00:30:01,862 --> 00:30:06,758
were just indicative
of that kind of overload.
409
00:30:06,862 --> 00:30:11,241
When metal breaks
due to overload or overstress,
it comes apart at an angle.
410
00:30:13,034 --> 00:30:16,655
But the fractured edges
of piece number 640
aren't angled,
411
00:30:16,758 --> 00:30:17,724
they're flat.
412
00:30:18,586 --> 00:30:20,137
What do you think?
413
00:30:20,241 --> 00:30:23,413
It's definitely not overstress.
It's metal fatigue.
414
00:30:26,206 --> 00:30:28,896
Fatigue fractures
happen when metal is stressed
415
00:30:29,000 --> 00:30:31,000
repeatedly over time
until it breaks.
416
00:30:32,413 --> 00:30:34,620
It looks very different
from a stress fracture.
417
00:30:36,724 --> 00:30:41,482
Typically,
a metal fatigue crack
will have a flat appearance.
418
00:30:41,586 --> 00:30:43,620
It'll be very smooth.
419
00:30:43,724 --> 00:30:45,103
That's exactly
the kind of crack
420
00:30:45,206 --> 00:30:48,000
that investigators observe
on piece number 640.
421
00:30:49,862 --> 00:30:52,068
That tells them
it didn't break off
the plane suddenly
422
00:30:52,172 --> 00:30:53,344
as it fell from the sky.
423
00:30:54,862 --> 00:30:58,379
This piece separated
from the plane over time.
424
00:30:58,482 --> 00:31:01,965
Had it caused the deaths
of 225 people?
425
00:31:03,448 --> 00:31:05,517
There was much more work
that needed to be done.
426
00:31:05,620 --> 00:31:07,896
A detailed analysis
of the piece
had to be done
427
00:31:08,000 --> 00:31:11,482
in order to see
if this, in fact,
was the smoking gun.
428
00:31:11,586 --> 00:31:14,793
There's something else about
this piece that stands out.
429
00:31:14,896 --> 00:31:16,827
It has a metal patch on it.
430
00:31:16,931 --> 00:31:18,965
It's called a doubler plate.
431
00:31:19,068 --> 00:31:21,310
It's the equivalent of a patch
on a punctured tire.
432
00:31:27,379 --> 00:31:31,379
It's not unusual
to find numerous doubler plates
on older planes like this one.
433
00:31:33,517 --> 00:31:38,206
A doubler plate is like a patch
that you put over fuselage skin.
434
00:31:38,310 --> 00:31:41,758
If there were
to be a tear,
435
00:31:41,862 --> 00:31:45,068
or a blemish,
a crack identified,
436
00:31:45,172 --> 00:31:48,103
you'd want to repair
the fuselage
back to its original strength.
437
00:31:48,206 --> 00:31:50,896
And one way to do that
is to put a doubler plate,
438
00:31:51,000 --> 00:31:55,137
or a patch right over
the existing structure.
439
00:31:55,241 --> 00:31:59,000
At some point,
this section of the 747
had been repaired.
440
00:32:00,655 --> 00:32:05,379
Investigators need to know
why it was fixed
and how that was done.
441
00:32:05,482 --> 00:32:08,482
We're looking for repair
to the aft lower lobe.
442
00:32:08,586 --> 00:32:10,517
Whatever it was, it was big.
443
00:32:12,724 --> 00:32:16,103
Investigators sift through 22 years
of documents.
444
00:32:19,137 --> 00:32:20,655
But the records are sketchy.
445
00:32:23,344 --> 00:32:26,344
Finding details
on one particular repair
could take time.
446
00:32:31,172 --> 00:32:33,586
There's something about
this particular doubler
447
00:32:33,689 --> 00:32:35,724
that catches
Frank Zakar's attention.
448
00:32:37,655 --> 00:32:43,241
The outside of the fuselage
contained longitudinal streaks
449
00:32:43,344 --> 00:32:47,103
that appeared to emanate
from between the doubler plate
and the skin.
450
00:32:49,034 --> 00:32:51,896
Something is leaking
from underneath the metal patch.
451
00:32:55,413 --> 00:33:00,172
Was there a possibility
that the skin had broken, cracked?
452
00:33:00,275 --> 00:33:05,586
And was there any fuel or air
coming out from between
the doubler and the fuselage?
453
00:33:05,689 --> 00:33:08,275
And that warranted
further examination.
454
00:33:09,034 --> 00:33:10,448
Let's cut it from here...
455
00:33:12,793 --> 00:33:14,448
to here.
456
00:33:14,551 --> 00:33:17,000
And send this piece
to Chung-Shan.
457
00:33:17,103 --> 00:33:19,689
In order to see
what's underneath the doubler,
458
00:33:19,793 --> 00:33:22,551
a large section of piece 640
is sent to a lab.
459
00:33:24,137 --> 00:33:27,655
No evidence has been found
of structural
or mechanical problems
460
00:33:27,758 --> 00:33:31,241
with Boeing's
747-200 airplanes.
461
00:33:31,344 --> 00:33:35,413
Taiwanese aviation officials
have no reason to keep
the planes on the ground.
462
00:33:39,517 --> 00:33:44,689
The Chung-Shan Institute
of Science and Technology
is a military research facility.
463
00:33:44,793 --> 00:33:47,344
It's at the forefront
of Taiwan's space program.
464
00:33:53,413 --> 00:33:57,000
This is where investigators
take a section
of piece number 640
465
00:33:57,103 --> 00:33:58,689
for a closer examination.
466
00:34:05,448 --> 00:34:09,448
The NTSB's Frank Zakar
finds a telling clue
on the crack itself.
467
00:34:14,896 --> 00:34:16,206
When I looked
at the fracture surface,
468
00:34:16,310 --> 00:34:21,000
I found
that this one specific area
was covered with aluminum oxide,
469
00:34:21,103 --> 00:34:24,551
pretty much similar
to rust on a car.
470
00:34:24,655 --> 00:34:28,862
Years of exposure
to oxygen changes
the color of metal.
471
00:34:28,965 --> 00:34:32,344
The discoloration
tells investigators
that this particular crack
472
00:34:32,448 --> 00:34:35,724
at the rear of the airplane
has been there
for a very long time.
473
00:34:39,448 --> 00:34:42,413
Then, when the doubler
is finally removed,
474
00:34:42,517 --> 00:34:45,517
investigators get a look
at the aluminum skin underneath.
475
00:34:46,689 --> 00:34:49,517
They're intrigued
by what they see.
476
00:34:49,620 --> 00:34:53,965
When we disassembled
the doubler plate
from the skin,
477
00:34:54,068 --> 00:34:58,517
we noticed that there was
some fairly long gouge marks.
478
00:34:58,620 --> 00:35:02,862
This is beyond
the kind of damage
a doubler is meant to patch.
479
00:35:02,965 --> 00:35:08,413
That was an "aha" moment,
that we... we might have
something here.
480
00:35:08,517 --> 00:35:11,068
The search
of the plane's documents
also pays off.
481
00:35:13,689 --> 00:35:19,000
The records contain
a very short reference
to a mishap 22 years earlier,
482
00:35:20,413 --> 00:35:22,275
when this plane
was only six months old.
483
00:35:23,241 --> 00:35:25,275
Speed is low sir, watch it.
484
00:35:25,379 --> 00:35:27,689
Its tail
scraped the runway
while landing.
485
00:35:29,965 --> 00:35:31,931
- Did you feel that?
- It happens
when a plane
486
00:35:32,034 --> 00:35:34,379
lands or takes off
at too steep an angle.
487
00:35:34,482 --> 00:35:36,551
It's called a tail strike.
488
00:35:36,655 --> 00:35:38,379
Dynasty 009,
Hong Kong tower.
489
00:35:38,482 --> 00:35:41,551
We observed smoke and sparks
from your tail on landing.
490
00:35:41,655 --> 00:35:43,896
Roger, Hong Kong Tower.
We'll have that looked at.
491
00:35:45,689 --> 00:35:48,586
Tail strike, sir.
I better log that.
492
00:35:48,689 --> 00:35:51,896
It is a relatively
common occurrence.
It's not a good thing.
493
00:35:52,000 --> 00:35:56,172
Some airplanes even have
what's called a bumper
in that portion of the fuselage,
494
00:35:56,275 --> 00:35:59,379
so that if the tail
ever does get too close
to the ground,
495
00:35:59,482 --> 00:36:01,689
instead of sacrificing skin
from the fuselage,
496
00:36:01,793 --> 00:36:04,551
you might have
the sacrificial bumper
that will take that wear.
497
00:36:06,275 --> 00:36:09,586
Tail strike damage
is routinely repaired.
498
00:36:09,689 --> 00:36:13,655
Investigators want to know
how China Airlines
went about fixing the plane.
499
00:36:17,758 --> 00:36:20,103
They could only find
a brief mention of the repairs
500
00:36:20,206 --> 00:36:21,310
that were done
in the plane's logbook.
501
00:36:23,965 --> 00:36:25,034
That's all there is?
502
00:36:25,137 --> 00:36:27,206
That's all we could find.
503
00:36:27,310 --> 00:36:30,827
There's not
a lot of detail
in China Airlines' records.
504
00:36:30,931 --> 00:36:36,551
China Airline indicating
they could not find any...
any of those documents.
505
00:36:36,655 --> 00:36:41,413
And when we start
looking for it,
we could not find any.
506
00:36:41,517 --> 00:36:44,655
And then they said
that they probably got lost.
507
00:36:44,758 --> 00:36:48,689
The documents
that do exist show that the day
after the tail strike,
508
00:36:48,793 --> 00:36:51,344
- China Airlines
did a temporary repair.
-
509
00:36:53,068 --> 00:36:56,137
Workers attached
a large aluminum plate
over the damaged area.
510
00:36:58,413 --> 00:37:00,827
What do we know about
the permanent repair?
511
00:37:00,931 --> 00:37:03,931
Doesn't get much better.
512
00:37:04,034 --> 00:37:07,103
A more
permanent repair was to be
carried out within four months.
513
00:37:09,827 --> 00:37:10,827
This is what we've got.
514
00:37:14,758 --> 00:37:15,965
The maintenance
records indicated
515
00:37:16,068 --> 00:37:17,310
that the permanent repair
was done
516
00:37:17,413 --> 00:37:19,862
in accordance
with Boeing recommendations
517
00:37:19,965 --> 00:37:22,586
in their Structural
Repair Manual.
518
00:37:22,689 --> 00:37:25,551
Evidence that we uncovered
indicate that the repair
was not done
519
00:37:25,655 --> 00:37:27,448
per the Boeing
repair manual.
520
00:37:30,655 --> 00:37:32,034
According to the manual,
521
00:37:32,137 --> 00:37:36,620
many of the scratches
on the plane were too deep
to be repaired.
522
00:37:36,724 --> 00:37:40,206
The entire damaged section
should have been cut out
and replaced.
523
00:37:42,275 --> 00:37:44,620
You have to follow
certain procedures,
524
00:37:44,724 --> 00:37:46,724
and that the Boeing
Structural Repair Manual
525
00:37:46,827 --> 00:37:49,655
indicating very clearly
what you should do
step by step.
526
00:37:50,448 --> 00:37:52,310
22 years later,
527
00:37:52,413 --> 00:37:54,827
investigators can tell that,
for some reason,
528
00:37:54,931 --> 00:37:57,517
the damaged piece
was not replaced.
529
00:37:57,620 --> 00:38:00,103
The scratches
from the tail strike
are still there.
530
00:38:02,965 --> 00:38:05,448
China Airlines engineers
tell investigators
531
00:38:05,551 --> 00:38:09,000
that the scratched area
was too large to cut out,
532
00:38:09,103 --> 00:38:12,000
so they sanded
the scratches down instead.
533
00:38:15,310 --> 00:38:17,758
In the event
of scratching,
534
00:38:17,862 --> 00:38:19,793
it depends on how deep
the scratches are.
535
00:38:19,896 --> 00:38:24,068
If they're not very deep,
they can be blended out.
536
00:38:24,172 --> 00:38:26,655
But if the scratches
are too deep,
537
00:38:26,758 --> 00:38:28,896
the repair technique
that's called for
538
00:38:29,000 --> 00:38:32,758
is to actually cut out
all of the scratched material
539
00:38:32,862 --> 00:38:38,758
and then design
a doubler patch that's larger,
by a big percentage,
540
00:38:38,862 --> 00:38:41,620
of the structure
that was originally removed.
541
00:38:43,310 --> 00:38:46,000
The scratches
weren't sanded down,
or cut out.
542
00:38:46,827 --> 00:38:47,724
They're still there.
543
00:38:50,896 --> 00:38:55,000
Maintenance workers
then made one final mistake.
544
00:38:55,103 --> 00:38:59,344
They put
the doubler plate right over
the scratched material.
545
00:39:02,448 --> 00:39:03,827
The doubler plate
that they put on
546
00:39:03,931 --> 00:39:08,241
was not 30 percent larger
than the affected area.
547
00:39:08,344 --> 00:39:12,206
In fact, it was barely,
maybe not even
in certain locations,
548
00:39:12,310 --> 00:39:14,517
larger than the area
that was scratched.
549
00:39:15,724 --> 00:39:17,413
Even though
the repair wasn't done
550
00:39:17,517 --> 00:39:19,793
according to Boeing's
instructions,
551
00:39:19,896 --> 00:39:23,965
the way it was logged
made it seem like it was.
552
00:39:24,068 --> 00:39:28,827
So, for 22 years,
anyone reading that entry
would assume the damaged area
553
00:39:28,931 --> 00:39:30,655
had been cut out,
as it should have been.
554
00:39:33,655 --> 00:39:36,551
Pieces were really
starting to fall into place now.
555
00:39:37,655 --> 00:39:39,344
Once we saw
this piece of structure
556
00:39:39,448 --> 00:39:42,689
- that had the fatigue cracks
in it...
-
557
00:39:42,793 --> 00:39:47,689
...and we realized that it
came from a structural repair
that was not done properly...
558
00:39:49,655 --> 00:39:52,103
...that was left to fly
for 20 years...
559
00:39:52,206 --> 00:39:55,068
Airborne, passing 1,600.
560
00:39:55,172 --> 00:39:56,448
...things began to make sense.
561
00:39:58,137 --> 00:40:01,034
By covering
an improper repair
with a doubler,
562
00:40:01,137 --> 00:40:04,793
and then documenting the repair
as meeting Boeing standards,
563
00:40:04,896 --> 00:40:08,103
the workers made their mistake
impossible to detect.
564
00:40:08,206 --> 00:40:11,517
What was so insidious
about this improper repair
565
00:40:11,620 --> 00:40:15,137
was that the doubler plate
hid all of the damage.
566
00:40:15,241 --> 00:40:19,344
So, if you weren't there,
watching them do
this repair improperly,
567
00:40:19,448 --> 00:40:22,068
you wouldn't know
that it was done improperly.
568
00:40:22,172 --> 00:40:25,137
You would have assumed
that the structure underneath
569
00:40:25,241 --> 00:40:27,206
had been cut out
the way it was supposed to.
570
00:40:29,275 --> 00:40:32,724
And every time
the plane took off
over the next 20 years,
571
00:40:32,827 --> 00:40:35,724
the concealed problem
got worse and worse.
572
00:40:38,793 --> 00:40:41,241
The air inside
a commercial airplane
is pressurized.
573
00:40:43,137 --> 00:40:46,206
As the plane climbs,
air is forced into the cabin
574
00:40:46,310 --> 00:40:50,448
to keep the pressure
inside the plane greater than
the pressure outside.
575
00:40:50,551 --> 00:40:55,862
It's like inflating a tire.
The inside air pushes against
the plane's skin.
576
00:40:55,965 --> 00:40:58,310
Each time
the airplane pressure rises,
577
00:40:58,413 --> 00:41:01,689
pressure builds up
inside the fuselage
of the airplane.
578
00:41:02,379 --> 00:41:04,724
That crack could open up
579
00:41:04,827 --> 00:41:11,241
for a certain amount of inches
or microns or millimeters.
580
00:41:11,344 --> 00:41:15,689
The plane's skin
expanded and contracted
a little bit every time.
581
00:41:15,793 --> 00:41:20,310
Because they weren't
properly repaired,
the cracks grew and spread.
582
00:41:20,413 --> 00:41:25,241
Eventually, the crack grew
into a stunning 2.3 meters.
583
00:41:25,344 --> 00:41:29,241
If you were charting the crack,
you would have seen
very slow growth early.
584
00:41:29,344 --> 00:41:32,655
But as time went on,
the growth was getting
bigger and bigger.
585
00:41:32,758 --> 00:41:35,586
A small scratch
had grown into
an enormous problem.
586
00:41:37,034 --> 00:41:41,620
Then, in May, 2002,
as Flight 611 climbed,
587
00:41:41,724 --> 00:41:45,758
that problem killed
225 people.
588
00:41:45,862 --> 00:41:49,655
As the airplane
climbed in altitude,
and the fuselage was pressured,
589
00:41:49,758 --> 00:41:52,448
that put enough strain
on this growing crack
590
00:41:52,551 --> 00:41:54,482
that it reached
its critical length.
591
00:41:54,586 --> 00:41:58,172
And, from there,
it just spread
like a spider web.
592
00:41:58,275 --> 00:42:02,862
It went in all directions,
and it probably looped
all the way around the fuselage
593
00:42:02,965 --> 00:42:05,827
to the point where the entire
aft section of the airplane
594
00:42:05,931 --> 00:42:09,103
just broke off
from the rest of the structure.
595
00:42:11,586 --> 00:42:14,068
The plane
went into a steep dive.
596
00:42:14,172 --> 00:42:18,931
The force of the air
on what was left of the plane
quickly ripped it to pieces.
597
00:42:24,000 --> 00:42:28,827
Investigators know
that an unseen crack caused
Flight 611 to break apart.
598
00:42:30,931 --> 00:42:34,206
They now discover
that China Airlines
came heartbreakingly close
599
00:42:34,310 --> 00:42:38,655
to finding that crack
and saving 225 lives.
600
00:42:42,620 --> 00:42:47,206
The China Airlines 747,
was in regular service
for 22 years
601
00:42:47,310 --> 00:42:50,068
following the improper repair
to its skin.
602
00:42:50,172 --> 00:42:53,344
It took off and landed
more than 20,000 times.
603
00:42:56,517 --> 00:42:59,310
Over the years,
mechanics would have
scrutinized the plane.
604
00:43:01,586 --> 00:43:04,137
There's regular inspections
per the Boeing
maintenance program
605
00:43:04,241 --> 00:43:05,896
that have to be performed
on the airplane.
606
00:43:10,137 --> 00:43:14,586
But the massive crack
forming at the rear of the plane
was never detected.
607
00:43:17,310 --> 00:43:19,724
Another accident
in another country
608
00:43:19,827 --> 00:43:23,275
almost led China Airlines
to discover the hidden damage.
609
00:43:26,034 --> 00:43:31,896
In 1988, the roof peeled off
an aging Boeing 737
owned by Aloha Airlines.
610
00:43:34,379 --> 00:43:36,103
As a result of that incident,
611
00:43:36,206 --> 00:43:38,034
the Federal Aviation
Administration
612
00:43:38,137 --> 00:43:40,827
laid out an inspection procedure
for older planes.
613
00:43:42,482 --> 00:43:45,482
Airlines around the world
were forced to inspect
their planes
614
00:43:45,586 --> 00:43:48,068
much more diligently
for corrosion and cracks.
615
00:43:50,034 --> 00:43:51,655
The regulation
called for airlines
616
00:43:51,758 --> 00:43:55,206
to re-evaluate
all existing repairs
to a plane's structure.
617
00:43:57,034 --> 00:44:00,206
Indications on this airplane
were that if they had looked
618
00:44:00,310 --> 00:44:02,551
at the maintenance records
and compared it to the repair,
619
00:44:02,655 --> 00:44:05,482
they would have had
to remove the repair
and redo it.
620
00:44:05,586 --> 00:44:07,551
China Airlines
took the first steps
621
00:44:07,655 --> 00:44:11,689
of the new procedure in 2001,
a year before the accident.
622
00:44:14,310 --> 00:44:16,551
The airline identified
and photographed
623
00:44:16,655 --> 00:44:19,896
thirty-one different doublers
on the 747,
624
00:44:20,000 --> 00:44:22,344
including the one
over the catastrophic crack.
625
00:44:24,724 --> 00:44:26,724
Those pictures
show investigators
626
00:44:26,827 --> 00:44:29,758
that China Airlines overlooked
a vital clue
627
00:44:29,862 --> 00:44:32,000
that could have warned them
of the looming danger.
628
00:44:34,758 --> 00:44:38,758
We examined the photographs
that China Airlines
took of the repair
629
00:44:38,862 --> 00:44:41,241
and noticed
that there was some issues
630
00:44:41,344 --> 00:44:44,379
that may have warranted
further investigation.
631
00:44:44,482 --> 00:44:48,310
Investigators see a dark brown stain
on the outside of the plane.
632
00:44:50,379 --> 00:44:52,241
It's the same
mysterious staining
633
00:44:52,344 --> 00:44:55,827
that led Frank Zakar to suspect
there was a hole
behind the doubler
634
00:44:55,931 --> 00:44:58,655
when he first saw it
on the pier.
635
00:44:58,758 --> 00:45:02,068
So why hadn't this stain
raised alarms before the crash?
636
00:45:05,965 --> 00:45:11,000
For years, passengers
on China Airlines' doomed 747
were allowed to smoke.
637
00:45:12,620 --> 00:45:16,517
They filled the pressurized air
with nicotine.
638
00:45:16,620 --> 00:45:19,758
The smoke was being forced out
through the crack
at the rear of the plane.
639
00:45:22,724 --> 00:45:26,724
Over time, that smoke
left a nicotine stain
on the outside of the plane.
640
00:45:27,793 --> 00:45:29,379
It was very vivid.
641
00:45:29,482 --> 00:45:33,896
Any experienced
maintenance engineer
642
00:45:34,000 --> 00:45:35,689
would be able to spot it
right immediately.
643
00:45:37,344 --> 00:45:39,793
Smoking hadn't been allowed
on China Airlines
644
00:45:39,896 --> 00:45:42,689
for seven years
before the crash.
645
00:45:42,793 --> 00:45:45,034
It tells investigators
that the crack in the plane
646
00:45:45,137 --> 00:45:47,000
had been there
for at least that long.
647
00:45:50,896 --> 00:45:54,793
But instead of investigating
the source of the staining...
648
00:45:54,896 --> 00:45:59,724
We need to conduct
the new inspection when we
do our next major check.
649
00:45:59,827 --> 00:46:03,896
...China Airlines
scheduled the second part
of the FAA's procedure,
650
00:46:04,000 --> 00:46:07,034
a detailed inspection
of the repaired areas.
651
00:46:07,137 --> 00:46:09,241
And that would be
the 7-C check,
652
00:46:10,586 --> 00:46:14,206
currently scheduled
for November the 2nd, 2002.
653
00:46:15,965 --> 00:46:20,137
But the 747
never made it
to November 2nd, 2002.
654
00:46:23,379 --> 00:46:25,310
It came apart
over the Taiwan Strait
655
00:46:25,413 --> 00:46:27,413
five months
before the inspection
656
00:46:27,517 --> 00:46:30,241
that would have, undoubtedly,
uncovered its hidden flaw.
657
00:46:34,724 --> 00:46:38,586
Investigators want to prevent
a similar accident
from ever happening again.
658
00:46:43,275 --> 00:46:46,103
They recommend
that aviation agencies
around the world
659
00:46:46,206 --> 00:46:49,793
immediately inspect repairs
for any possible hidden damage.
660
00:46:53,793 --> 00:46:56,965
We were no longer
gonna accept
just a quick write-up
661
00:46:57,068 --> 00:46:59,344
that the repair
was done properly.
662
00:46:59,448 --> 00:47:02,310
If the repair didn't have
all the necessary documentation
663
00:47:02,413 --> 00:47:05,137
to allow us to know
it was done properly,
664
00:47:05,241 --> 00:47:09,172
we were requiring operators
to take doubler plates off
665
00:47:09,275 --> 00:47:13,137
and do a visual inspection
of the structure underneath.
666
00:47:13,241 --> 00:47:15,275
The National Transportation
Safety Board
667
00:47:15,379 --> 00:47:16,724
issues its own recommendations.
668
00:47:18,517 --> 00:47:20,620
The board asks
that maintenance personnel
669
00:47:20,724 --> 00:47:23,689
be warned of the consequences
of hiding the kind of damage
670
00:47:23,793 --> 00:47:26,344
that could lead
to the structural failure
of an airplane.
671
00:47:29,586 --> 00:47:34,344
The moral of this story
is that the repair
has to be done properly.
672
00:47:34,448 --> 00:47:37,793
As a mechanic,
when you're doing work
on an airplane,
673
00:47:37,896 --> 00:47:39,448
you're not thinking
about the people
674
00:47:39,551 --> 00:47:43,655
who might be flying
on that fuselage
20 years from now.
675
00:47:43,758 --> 00:47:48,931
But their safety depends on you
doing the repair properly.
676
00:47:49,034 --> 00:47:54,517
China Airlines
has revised the way its fleet
is inspected and maintained.
677
00:47:54,620 --> 00:47:58,655
Its safety record
has improved dramatically
since the crash of Flight 611.
678
00:48:02,137 --> 00:48:05,586
Investigators also proposed
the development of new tools
679
00:48:05,689 --> 00:48:08,241
that would allow mechanics
to detect damage
behind a doubler.
680
00:48:09,310 --> 00:48:11,137
Such tools are being used today.
681
00:48:12,724 --> 00:48:15,448
Boeing developed
a non-destructive procedure
682
00:48:15,551 --> 00:48:20,206
that can find cracks
in the fuselage
underneath a doubler.
683
00:48:20,310 --> 00:48:24,344
That device
uses ultrasound, sound waves
that travel through metal.
684
00:48:25,689 --> 00:48:30,103
It can reveal damage
underneath a doubler.
685
00:48:30,206 --> 00:48:33,551
It's the same technology
that allows doctors
to observe a fetus
686
00:48:33,655 --> 00:48:36,000
while it's still inside
the womb.
687
00:48:36,103 --> 00:48:38,172
The device would have been
able to detect
688
00:48:38,275 --> 00:48:40,517
the crack behind
Flight 611's doubler plate.
689
00:48:41,931 --> 00:48:44,758
But the technology
has some limitations.
690
00:48:44,862 --> 00:48:47,137
A great number of hours
are required just to do
691
00:48:47,241 --> 00:48:49,241
one specific area
of the airplane.
692
00:48:50,448 --> 00:48:53,586
But the technology
is getting better.
693
00:48:53,689 --> 00:48:57,482
The problems
that led to the China Airlines
disaster are not going away.
694
00:48:59,827 --> 00:49:01,862
Planes the world over
are getting older.
695
00:49:03,862 --> 00:49:07,275
And older planes need to be more
thoroughly inspected for cracks.
696
00:49:10,137 --> 00:49:12,931
Six years
after the China Airlines crash,
697
00:49:13,034 --> 00:49:18,103
Southwest Airlines
in the United States was hit
with a record-breaking fine.
698
00:49:18,206 --> 00:49:23,931
$10.2 million
for missing inspections
designed to find cracks.
699
00:49:24,034 --> 00:49:26,482
The fining of Southwest
brings back into focus
700
00:49:26,586 --> 00:49:29,827
how important it is
to do maintenance properly
on an airplane.
701
00:49:32,344 --> 00:49:36,000
A proper program
of maintenance and inspections
can be costly.
702
00:49:37,724 --> 00:49:39,827
But, as China Airlines showed,
703
00:49:39,931 --> 00:49:44,448
the price of not maintaining
aging planes is even costlier.