Dangerous rudders for 737s?
A ‘Dateline’ investigation shows more than 100 incidents where
pilots reported problems with the aircraft’s controls
March 10 — Getting on an airplane is an act of faith.
You really have to trust everyone and everything
involved — the pilots, the maintenance workers,
the equipment itself. But what if there was a
problem no one could see or stop? Two years ago,
“Dateline” first reported on a potential danger in
the design of the Boeing 737 aircraft that some
believe may have contributed to two deadly
crashes. The FAA ordered the manufacturer to fix
it. But now “Dateline” has uncovered some
disturbing information about how that effort is
going and about a possible new threat as well.
Chris Hansen reports a “Dateline” investigation.
“IT WAS OUR worst nightmare coming true. You’re
very apprehensive and you know there’s always that chance
something could happen. And you just never think it’ll
happen to you.”
What happened to Susan Brochu and her three
daughters came at the end of a Florida vacation less than
two weeks ago. They were returning home to Connecticut
on a US Airways Metrojet flight, packed with families fresh
from vacations in Orlando.
Susan Brochu: “We had a beautiful take-off. And you
know, cruised and got right up to 33,000 feet and as soon
as we had our snacks that’s when all the trouble started.”
Chris Hansen: “What was the first indication you had
there was trouble?”
Brochu: “The plane just started to tip. Tip to the right.
And then just drop. It dropped suddenly. And the feeling
that I was losing my stomach. Just totally out of the blue,
unexpected, and it was shocking. ”
Brochu says the plane shook and shuddered for five
terrifying minutes before finally leveling off. Then the captain
made an announcement that would un-nerve even the most
seasoned flier: their jet was experiencing a “flight control
problem” and they would be making an emergency landing
in Baltimore. “As soon as he said that word, “emergency
landing” that’s when I started getting panicky inside,” says
Brochu.
As the jet descended, flight attendants briefed
passengers on emergency procedures and evacuation but
pilots ultimately landed the plane safely in Baltimore.
While it’s still too early to say for sure what caused the
mid-air loss of control, the incident has drawn intense
scrutiny from investigators at the National Transportation
Safety Board because of the kind of jetliner involved — a
Boeing 737.
Workhorse in the sky
Facts about the Boeing 737
The 737 is the workhorse of the American fleet.
Worldwide there are more than 3,000 of them in
service.
A 737 takes off every seven seconds.
It's considered to be among the safest and most
reliable planes in the sky. In spite of that enviable
record, two Boeing 737s have been involved in
catastrophic crashes that remain unsolved.
Investigators are closely examining the US Airways
Metrojet incident to see if it was triggered by a critical
problem that they say has plagued the 737 for years: a
rudder malfunction.
It’s a problem the Federal Aviation Administration
pledged to fix two years ago. But it’s a problem that is still
occurring in numbers greater than previously reported.
The 737 is the workhorse of the American fleet.
Worldwide there are more than 3,000 of them in service. A
737 takes off every seven seconds. It’s considered to be
among the safest and most reliable planes in the sky.
In spite of that enviable record, two Boeing 737s have
been involved in catastrophic crashes that remain unsolved.
And the mystery that surrounds those crashes has made the
737 the focus of one of the most exhaustive investigations
ever.
TWO DEADLY CRASHES
Eight years ago in Colorado Springs, Colorado, United
Airlines Flight 585, a Boeing 737, crashed on approach. “It
was about a thousand feet off the ground. It flipped upside
down and went into the ground like a rocket in 7 seconds.
And it was over. It created a crater that was 40 feet deep.
Everyone died immediately — there were 25 wonderful
people that died that day,” says Gail Dunham.
Dunham’s late ex-husband, Hal Green, was one of
those 25 people and the plane’s captain.
“These (refers to pilot wings) are the wings that Hal
wore on March 3 of ’91. The distress on them is incredible
from the force of the accident — you can still see the
threads from the uniform on the other side,” says Dunham.
In September 1994, there would be another incident: a
mirror image of what happened in Colorado Springs. USAir
Flight 427, another Boeing 737, crashed on approach to
Pittsburgh, killing all 132 people on board.
The wooded ravine where USAir Flight 427 crashed
outside of Pittsburgh in September 1994, killing 132 people.
So what could have caused the two 737s to spiral out
of control? Because of the way the jets flipped, investigators
immediately suspected the rudder.
RUDDER STEERS THE PLANE
The rudder is the vertical panel attached to the tail that
steers the plane left or right. It’s moved by pedals in the
cockpit. The pilot pushes the right rudder pedal, the plane
turns right. He pushes the left rudder pedal, it turns left.
Federal investigators discovered that in certain rare
conditions the rudder’s control unit could malfunction —
causing the rudder to move on its own to one side, and jam.
It’s called a rudder hardover and if it happens in flight it can
cause a plane to flip out of control. Could this be the
explanation for what caused the two 737s to crash?
Boeing, the 737s manufacturer, says no: that the
company’s own experts concluded the Colorado crash was
mostly likely caused by a freak gust of wind reported
blowing off the Rocky Mountains that day.
And the Pittsburgh crash? Boeing argued that jet was
jostled by the wake turbulence from another plane and that
Flight 427’s pilots may have been startled and lost control.
“These are Boeing airplanes — they’re safe, they’re
reliable, they transport millions of people around the world,”
says Allan Mulally. Mulally is a division president with
Boeing. He spoke to “Dateline” when we last looked at the
737 two years ago.
Mulally said that while Boeing’s own simulations also
confirmed that in certain conditions, the rudder could move
on it’s own and jam — no one has been able to prove this
has ever actually happened in flight.
Chris Hansen: “Is it possible for a rudder on a 737 to
go hard over, uncommanded?”
Allan Mulally: “In all the experience that we’ve had
with the 737 — which has an extensive background of 27
years — we’ve never had a rudder hardover.”
PILOT AVERTS DISASTER
But as the federal government continued its
investigation, there would be another critical incident in June
1996, when 737 pilot Brian Bishop says he narrowly
averted disaster.
Bishop was at the controls of an Eastwind Airlines 737
carrying 48 passengers. As he was going through his final
preparations for a routine landing in Richmond, Virginia, he
felt an unusual thump. Bishop says, “the airplane veered
hard to the right — it was very steep, and it was very fast.
Very abrupt.”
Bishop was caught in the grip of every pilot’s worst
nightmare: a critical control problem. He says his 737 was
locked in a steep bank — literally on its side. “Something
like this where an airplane is not controllable, is unique.
Rarely happens. I’ve never had it happened to me and it
was probably the sickest feeling I’ve ever had in an
airplane,” says Bishop.
Bishop also says the controls that move the plane’s
rudder were inexplicably frozen. But then, just as quickly
and mysteriously as the phantom force took hold of his
plane, it vanished. He landed the jet safely at the Richmond
airport a few minutes later.
The NTSB detailed its investigation of Bishop’s near
crash in a 1996 report — noting that it had also been
informed of numerous other 737 rudder incidents. How
many? The report didn’t say exactly.
But “Dateline” went back and ran its own computer
analysis — sifting through tens of thousands of incident
reports compiled in databases by the NTSB, the FAA, and NASA.
We found pilot reports of the rudder moving on its own
dating back more than 20 years — 123 in all — a tiny
fraction of the number of 737 flights, and none causing other
crashes. But some malfunctions were termed “severe.” In
1994 a Continental 737 at 37,000 feet rolled violently on its
side. It continued for 18 frightening minutes before the pilot
was able to regain control.
In 1995 a British Airways jet at 20,000 feet rolled
uncontrollably from side to side for seven minutes.
And in 1996, a pilot reported his 737 rolled left, then
right on landing. He said it was as if the rudder had a “mind
of its own” and that in his years of flying “this was the first
time he felt an aircraft was out of control.”
FAA ORDERS CHANGES
In January of 1997, even though federal investigators
couldn’t pinpoint exactly what was going wrong, the FAA
ordered Boeing to make sweeping design changes in the
737 rudder system — and install the fixes on more than
3,000 planes worldwide. Final repairs must be completed
by July 2000, but the most urgent fix to the rudder’s control
systems must be completed by August of this year.
So when we learned that investigators suspected a
rudder malfunction may have caused that US Airways
Metrojet to make an emergency landing two weeks ago, we
decided to check to see how many 737s had been fixed as
the FAA ordered and to see if those fixes solved the problem.
We found that in the two years since the FAA’s order,
only one-third of some 3,000 planes have been fixed —
leaving less than five months to complete work on the
remaining two-thirds, before the first deadline.
Chris Hansen: “Will you make that August ’99 deadline?”
Thomas McSweeney: “At this point, the FAA has no
plans to extend either one of those limits.”
Thomas McSweeney is an associate administrator for
the FAA. He says, despite the amount of work that remains
ahead, he’s confident that airlines will meet the August deadline.
“It’s certainly going to present difficulties to the airlines.
But we have no intention of relieving them of that regulatory
burden, of complying by August,” says McSweeney.
But now there may be a new concern: cracks have
been found in some of the newly designed parts intended to
prevent rudder malfunctions. The FAA has ordered that all
new parts already installed on planes must now be checked.
How serious is the problem? FAA safety documents
say one crack isn’t unsafe. But two? The agency says that
could cause a rudder hardover in flight — the same
potentially catastrophic problem the new part is supposed to prevent.
And what about pilot reports of rudder difficulties in
flight? According to the “Dateline” computer analysis,
problems persist. We discovered that in the two years since
the FAA first ordered that the rudder system be redesigned,
pilots have continued to file reports of the 737’s rudder
moving itself — almost 50 in all. And while none of these
resulted in crashes, many pilots classified the problems as
“critical.” Reports include 11 emergency landings; an
emergency descent; an aborted takeoff; and an aborted landing.
And “Dateline” has learned that the NTSB is
investigating two incidents of 737s that have had suspected
rudder malfunctions — after they were fitted with the new
rudder control units.
One is that US Airways Metrojet that Susan Brochu
was on two weeks ago. And only days before that, pilots
on a United 737 reported rudder problems while preparing
for takeoff in Seattle.
Chris Hansen: “Does that indicate that more fixes are
necessary or that maybe this fix wasn’t enough?”
Thomas McSweeney: “At this point in the
investigation it’s too early in the investigation to really know
what needs to be done with this rudder.
Gail Dunham: “It’s been eight years since the
Colorado Springs 737 crash and people still are not
guaranteed the safest 737 possible.”
Only days ago, Gail Dunham and other family members
observed the eighth anniversary of the crash that killed their
loved ones. Since that crash, Dunham has become an
outspoken safety advocate: serving as president of the
National Air Disaster Alliance. She has testified before
Congress, and relentlessly lobbied aviation officials to speed
up 737 fixes that, she worries, are taking too long. “I realize
we haven’t had a catastrophic crash since 1994 but the
potential is still there,” says Dunham.
But the FAA and Boeing say they’re doing all they can,
ordering additional inspections and special training to teach
pilots how to recover from a serious rudder incident, and avoid disaster.
Chris Hansen: “Is the 737 as it is today, a safe plane to fly on?”
Thomas McSweeney: “The 737 has a high, very high
safety record. The changes that we’re requiring to be made
in this year and next year are going to make a safe airplane even safer.”
Later this month, the National Transportation Safety
Board is expected to announce its findings on what caused
one catastrophe involving a Boeing 737 — the US Air flight
that crashed on approach to Pittsburgh in 1994.
