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Rick Umali
November 3rd 06, 04:32 AM
Last night I watched a fascinating documentary on the History Channel,
titled (I think) "Flight 191". This is the American Airlines DC-10 crash on
March 25, 1979, in which 270+ were killed, after the No. 1 engine blew off
its wing. (I was only eleven when this happened.)

In the last part of the program, the subject turned to the recovery
procedures used by the pilots. I'm not a pilot, so I'll have to paraphrase,
but essentially the plane could have still been flown with its missing
engine if the pilots recognized they were in a stall (the pilot in question
didn't have a "stick shaker" to warn him of this).

I don't doubt it's possible to still fly a DC-10 with one engine missing,
but a lot of things have to go right to turn it around and land, yes? Can
anyone recall a commercial aircraft recovery from a blown engine?
--
Rick (www.snipurl.com/rickumali) Umali

Kingfish
November 3rd 06, 04:48 AM
Rick Umali wrote:
> Last night I watched a fascinating documentary on the History Channel,
> titled (I think) "Flight 191". This is the American Airlines DC-10 crash on
> March 25, 1979, in which 270+ were killed, after the No. 1 engine blew off
> its wing. (I was only eleven when this happened.)
>
> In the last part of the program, the subject turned to the recovery
> procedures used by the pilots. I'm not a pilot, so I'll have to paraphrase,
> but essentially the plane could have still been flown with its missing
> engine if the pilots recognized they were in a stall (the pilot in question
> didn't have a "stick shaker" to warn him of this).
>
> I don't doubt it's possible to still fly a DC-10 with one engine missing,
> but a lot of things have to go right to turn it around and land, yes? Can
> anyone recall a commercial aircraft recovery from a blown engine?
> --

No stick shaker in a DC-10? I find that hard to believe, I thought all
transport category jets built in the last 35 years had that system, but
I'm not a jet pilot.
I don't know that it IS possible to fly that plane with a missing wing
engine considering there was probably a major hydraulic system failure
when the engine tore off its mounts. Countering the asymmetric thrust
condition without rudder would make that impossible I'd think. A
similar thing happened in 1989(?) in Sioux City when Capt. Al Haines
landed (more or less) a crippled DC-10 when the tail mounted #2 engine
had an uncontained fan disk failure that took out all three hyd systems
leaving differential engine thrust as the only method of control. The
fact that anybody walked away from that crash was amazing - That the
majority of passengers did qualifies as a miracle.

Grumman-581[_1_]
November 3rd 06, 05:11 AM
Kingfish wrote:
> No stick shaker in a DC-10? I find that hard to believe, I thought all
> transport category jets built in the last 35 years had that system, but
> I'm not a jet pilot.

Actually, one stick shaker came standard on the aircraft, the other one
was an option... AA did not choose to avail themselves of that option
though... When Flight 191 lost the left engine, it also lost the
generator that provided electrical power to the stick shaker... The loss
of the engine also took out both sets of hydraulic lines in the left
wing... The slats retracted upon loss of hydraulic fuel in those
lines... Procedures at that time were to go to V2, even if they were
above V2 at that time... In this incident, they were already above V2...
If they had stayed there, they would have most likely been able to
land the plane safely... Slowing to V2 caused the left wing to stall,
but the right wing did not due to the slats still being extended on
it... Of course, it goes into a roll to the left and impacts the ground
with significant force... Typical 3 links in the chain of events leading
up to the accident...

1 -- Maintenance problems with the AA mechanics who used a procedure to
change the engines on the aircraft that was not only not approved by the
aircraft manufacturer, but the manufacturer had explicitly told them
that they shouldn't be using...
2 -- No stick shaker on the other yoke... If they had known that they
were starting to stall as they decreased to V2, they could have
increased their speed and kept it from stalling and the roll developing...
3 -- Incorrect emergency procedures... Subsequent revisions to the
emergency procedures said that if you are already above V2, don't
decrease your speed...

> I don't know that it IS possible to fly that plane with a missing wing
> engine considering there was probably a major hydraulic system failure
> when the engine tore off its mounts. Countering the asymmetric thrust
> condition without rudder would make that impossible I'd think.

Actually, it shouldn't be as bad as some aircraft since it has 3 engines
and as such, the dissymmetry of thrust would not be as great...

Guy Elden Jr
November 3rd 06, 05:21 AM
> 2 -- No stick shaker on the other yoke... If they had known that they
> were starting to stall as they decreased to V2, they could have
> increased their speed and kept it from stalling and the roll developing...

Not sure exactly how the stick shakers in the big planes work, only
familiar with a C-172, which has only one port on the left wing to feed
what essentially amounts to a kazoo to inform the pilot that the plane
is about to stall. Did that particular DC-10 have a port on each wing,
and if so, would both ports have fed both stick shakers? If not, I
don't see how adding a second stick shaker would have necessarily
helped to recognize a stall, especially if only one wing was stalling
at the time.

--
Guy

Jim Macklin
November 3rd 06, 06:18 AM
Yes, a DC-10 at Tulsa had both wing mounted engines fail
after sucking up about 10,000 sparrows. Came around on just
the tail engine.

The problem with flight 191 was that the crew did not know
the slat had retracted. Since lift varies by the sq.root of
the speed, the wing would not be stalled at V2, but with the
slat retracted, the effect was greater than the combined
effect of rudder and aileron anti-roll command. At 300 feet
they just wasn't time to figure it out.


--
James H. Macklin
ATP,CFI,A&P

"Rick Umali" > wrote in message
...
| Last night I watched a fascinating documentary on the
History Channel,
| titled (I think) "Flight 191". This is the American
Airlines DC-10 crash on
| March 25, 1979, in which 270+ were killed, after the No. 1
engine blew off
| its wing. (I was only eleven when this happened.)
|
| In the last part of the program, the subject turned to the
recovery
| procedures used by the pilots. I'm not a pilot, so I'll
have to paraphrase,
| but essentially the plane could have still been flown with
its missing
| engine if the pilots recognized they were in a stall (the
pilot in question
| didn't have a "stick shaker" to warn him of this).
|
| I don't doubt it's possible to still fly a DC-10 with one
engine missing,
| but a lot of things have to go right to turn it around and
land, yes? Can
| anyone recall a commercial aircraft recovery from a blown
engine?
| --
| Rick (www.snipurl.com/rickumali) Umali

Jim Macklin
November 3rd 06, 06:24 AM
That accident was almost a successful landing, right up to
the point that they dropped the gear. They had a stabilized
approach to a belly landing, the change in drag with the
gear dropping required major adjustments to power. Had they
landed gear up and there was one death, you can expect that
the lawyers would have sued the pilot and airline. When you
get a first time event, with not previously flight test
procedure, the pilot should be given a medal and a writ that
bans a suit against the pilot, no matter what happened.


"Kingfish" > wrote in message
oups.com...
|
| Rick Umali wrote:
| > Last night I watched a fascinating documentary on the
History Channel,
| > titled (I think) "Flight 191". This is the American
Airlines DC-10 crash on
| > March 25, 1979, in which 270+ were killed, after the No.
1 engine blew off
| > its wing. (I was only eleven when this happened.)
| >
| > In the last part of the program, the subject turned to
the recovery
| > procedures used by the pilots. I'm not a pilot, so I'll
have to paraphrase,
| > but essentially the plane could have still been flown
with its missing
| > engine if the pilots recognized they were in a stall
(the pilot in question
| > didn't have a "stick shaker" to warn him of this).
| >
| > I don't doubt it's possible to still fly a DC-10 with
one engine missing,
| > but a lot of things have to go right to turn it around
and land, yes? Can
| > anyone recall a commercial aircraft recovery from a
blown engine?
| > --
|
| No stick shaker in a DC-10? I find that hard to believe, I
thought all
| transport category jets built in the last 35 years had
that system, but
| I'm not a jet pilot.
| I don't know that it IS possible to fly that plane with a
missing wing
| engine considering there was probably a major hydraulic
system failure
| when the engine tore off its mounts. Countering the
asymmetric thrust
| condition without rudder would make that impossible I'd
think. A
| similar thing happened in 1989(?) in Sioux City when Capt.
Al Haines
| landed (more or less) a crippled DC-10 when the tail
mounted #2 engine
| had an uncontained fan disk failure that took out all
three hyd systems
| leaving differential engine thrust as the only method of
control. The
| fact that anybody walked away from that crash was
amazing - That the
| majority of passengers did qualifies as a miracle.
|

Ron Wanttaja
November 3rd 06, 07:07 AM
On Fri, 3 Nov 2006 00:24:54 -0600, "Jim Macklin"
> wrote:

>That accident was almost a successful landing, right up to
>the point that they dropped the gear.

Wrong accident...you're thinking of United 232 in Sioux City. American 191 is
the one in Chicago where the engine pod physically broke free of the wing right
after takeoff. 271 dead, no survivors.

I have my own strange connection to the Chicago accident. I was an on-duty
operator for a USAF missile launch detection satellite which operated in the IR
spectrum. We detected the heat from the crash.

Ron Wanttaja

Grumman-581[_3_]
November 3rd 06, 07:30 AM
Here's some more information on the accident...

http://www.rvs.uni-bielefeld.de/publications/Incidents/DOCS/ComAndRep/OHare/NTSB/COPY/ohare-full.html

Ron Natalie
November 3rd 06, 12:17 PM
Rick Umali wrote:

>
> In the last part of the program, the subject turned to the recovery
> procedures used by the pilots. I'm not a pilot, so I'll have to paraphrase,
> but essentially the plane could have still been flown with its missing
> engine if the pilots recognized they were in a stall (the pilot in question
> didn't have a "stick shaker" to warn him of this).
>
The problem was not that they stalled. The problem is that when the
wing departed it caused the leading edge slat on that side not to
extend. When they slowed down to the single engine best rate
of climb speed (which was the proper official procedure), the
ONE SIDE stalled. I'm not sure a stick shaker or other stall
warning would have helped here unless there was a specific design
for the assymetric configuration that happened.

Had they symmetrically stalled, they would have just controllably
lost altitude and might have even recovered.

James Robinson
November 3rd 06, 02:25 PM
"Guy Elden Jr" > wrote:

>> 2 -- No stick shaker on the other yoke... If they had known that they
>> were starting to stall as they decreased to V2, they could have
>> increased their speed and kept it from stalling and the roll
>> developing...
>
> Not sure exactly how the stick shakers in the big planes work, only
> familiar with a C-172, which has only one port on the left wing to
> feed what essentially amounts to a kazoo to inform the pilot that the
> plane is about to stall. Did that particular DC-10 have a port on each
> wing, and if so, would both ports have fed both stick shakers? If not,
> I don't see how adding a second stick shaker would have necessarily
> helped to recognize a stall, especially if only one wing was stalling
> at the time.

As I recall, the problem wasn't that there was only one stick shaker
motor, but that the stick shaker motor, the captain's instruments, the
slat disagreement alarm and the two stall warning computers were powered
from a generator on the engine that was lost. There was no redundancy.

The backup power switch was located in the panel over the captain's head,
and to the rear, also out of reach of the flight engineer, so in the heat
of the moment, it was not used.

Further, only the outboard slats had retracted on the left wing, with the
inboard properly deployed, so there likely was no tell-tale buffeting of
the tail to give the crew any clue that the wing was stalling.

Jim Macklin
November 3rd 06, 04:43 PM
I was speaking about ANOTHER accident that had been asked
about. I was speaking about the Sioux City accident. I had
already addressed the 191 slat retract.



"Ron Wanttaja" > wrote in message
...
| On Fri, 3 Nov 2006 00:24:54 -0600, "Jim Macklin"
| > wrote:
|
| >That accident was almost a successful landing, right up
to
| >the point that they dropped the gear.
|
| Wrong accident...you're thinking of United 232 in Sioux
City. American 191 is
| the one in Chicago where the engine pod physically broke
free of the wing right
| after takeoff. 271 dead, no survivors.
|
| I have my own strange connection to the Chicago accident.
I was an on-duty
| operator for a USAF missile launch detection satellite
which operated in the IR
| spectrum. We detected the heat from the crash.
|
| Ron Wanttaja

Mxsmanic
November 3rd 06, 09:15 PM
Ron Wanttaja writes:

> I have my own strange connection to the Chicago accident. I was an on-duty
> operator for a USAF missile launch detection satellite which operated in the IR
> spectrum. We detected the heat from the crash.

Are you saying anything you shouldn't?

--
Transpose mxsmanic and gmail to reach me by e-mail.

Robert M. Gary
November 4th 06, 12:21 AM
Jim Macklin wrote:
> Yes, a DC-10 at Tulsa had both wing mounted engines fail
> after sucking up about 10,000 sparrows. Came around on just
> the tail engine.
>
> The problem with flight 191 was that the crew did not know
> the slat had retracted. Since lift varies by the sq.root of
> the speed, the wing would not be stalled at V2, but with the
> slat retracted, the effect was greater than the combined
> effect of rudder and aileron anti-roll command. At 300 feet
> they just wasn't time to figure it out.

Running both hydralic lines (allowing the slats to retract) within
inches of eash other was perhaps a questional decision.

-Robert

Ron Wanttaja
November 4th 06, 02:07 AM
On Fri, 03 Nov 2006 22:15:41 +0100, Mxsmanic > wrote:

>Ron Wanttaja writes:
>
>> I have my own strange connection to the Chicago accident. I was an on-duty
>> operator for a USAF missile launch detection satellite which operated in the IR
>> spectrum. We detected the heat from the crash.
>
>Are you saying anything you shouldn't?

All the time, why?

Ron Wanttaja

Jim Macklin
November 4th 06, 07:25 AM
It was OK on the DC-9 and nobody considered the difference
on the DC-10. Yes it was a bad design as was not using
hydraulic fuses and not having essential power as is now
required on Part 25, perhaps because of what was learned
from 191.



"Robert M. Gary" > wrote in message
oups.com...
|
| Jim Macklin wrote:
| > Yes, a DC-10 at Tulsa had both wing mounted engines fail
| > after sucking up about 10,000 sparrows. Came around on
just
| > the tail engine.
| >
| > The problem with flight 191 was that the crew did not
know
| > the slat had retracted. Since lift varies by the
sq.root of
| > the speed, the wing would not be stalled at V2, but with
the
| > slat retracted, the effect was greater than the combined
| > effect of rudder and aileron anti-roll command. At 300
feet
| > they just wasn't time to figure it out.
|
| Running both hydralic lines (allowing the slats to
retract) within
| inches of eash other was perhaps a questional decision.
|
| -Robert
|

Blanche
November 5th 06, 12:20 AM
Mxsmanic > wrote:
>Ron Wanttaja writes:
>
>> I have my own strange connection to the Chicago accident. I was an on-duty
>> operator for a USAF missile launch detection satellite which operated
>in the IR
>> spectrum. We detected the heat from the crash.
>
>Are you saying anything you shouldn't?

It's common and public knowledge that one of NORAD's responsibilities
is to monitor missle launches.

www.norad.mil/about_us.htm

Mxsmanic
November 5th 06, 02:17 AM
Blanche writes:

> It's common and public knowledge that one of NORAD's responsibilities
> is to monitor missle launches.

Yes, but the exact monitoring capabilities of satellites may not be
public knowledge (although they aren't necessarily always classified,
either).

--
Transpose mxsmanic and gmail to reach me by e-mail.

Ron Wanttaja
November 5th 06, 03:35 AM
On Sun, 05 Nov 2006 03:17:21 +0100, Mxsmanic > wrote:

>Blanche writes:
>
>> It's common and public knowledge that one of NORAD's responsibilities
>> is to monitor missle launches.
>
>Yes, but the exact monitoring capabilities of satellites may not be
>public knowledge (although they aren't necessarily always classified,
>either).

"In recent years, scientists have been developing methods to use DSP's infrared
sensor as part of an early warning system for natural disasters...."

http://spaceflightnow.com/titan/b39/040210dsp.html

Ron Wanttaja

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