Moderators: jsumali2, richierich, ua900, PanAm_DC10, hOMSaR

 
coa747
Topic Author
Posts: 380
Joined: Wed Jul 13, 2005 3:11 pm

American Airlines 587 A Closer Look

Wed Aug 24, 2005 1:03 pm

As a grad student enrolled in the Safety Science program at Embry-Riddle, who hopes to go to work for the NTSB after graduation I was naturally curious as to the findings of this investigation. However after reading the NTSB report and then reading an article by Lee Gaillard in the July 2005 edition of Airways Magazine. I have some doubts as to the boards findings. Namely as to captain Sten Molin's excessive control inputs being the cause of this accident. The NTSB for whatever reason did not include in its published findings the following information. Information that revealed a pattern of uncommanded rudder incidents, and information from Airbus internal testing that proves they were aware of rudder issues prior to the crash of 587.

1. A 68+ page report from American pilots detailing specific incidents of uncommanded rudder deflection on the A300, many of which were serious enough to require an emergency landing.

Example 1- January 17, 2002 a Caracas bound A300 experienced significant uncommanded rudder inputs climbing through 10,000 ft. Accelerating through 290kt the pilots experienced smooth, uncommanded yawing severe enough to force buckling and popping sounds from passenger exit doors, necesitating and immediate return to Miami.

Example 2- January 1990: A300 diverted to Bermuda following continuous uncontrollable rudder deflections and multiple system failures; on landing, a severe uncommanded yaw almost forced it off the runway

2. FedEx experienced related issues with its Airbus fleet also not included in the final report.

Example- February 1, 2002 mechanics trouble-shooting an A300's rudder problem found composite delamination and a bent rudder control rod. In the hangar sudden violent rudder oscillations occured when the hydraulic system was pressurized and the rudder pedal depressed. In flight rudder problems returned following the repairs.

3. Under pressure from the pilot union representative at an October 2002 NTSB hearing, the Airbus expert finally admitted that the manufacturer had quietly modified the A300 control system software for passenger comfort following the crash of flight 587. As a result the number of uncommanded rudder incidents subsequently decreased.

4. The accident aircraft's previous day log entry recorded significant problems with the computerized flight management system. While flight 587 prepared for departure the day of the crash the pilots reported yaw damper and pitch-trim malfunctions-that aircraft's 11th computer linked pitch-trim problem within a year.

5. Airbus parameters for stress-testing its composite fins were not realistic given the real world operating conditions of the aircraft. The tests were carried out at a constant ground temperature of 70 degrees C and 70% humidity while American Airlines A300's routinely experienced temperature shifts of 83 degrees C from the ramp at Miami to altitude and a humidity swing of 80% or more. Composite structures become brittle when cold and soft when heated. What happens over 13 years of 14,934 cycles and 37,550 flight hours when a composite fin is subjected to in-flight turbulence at different altitudes after a heat or cold soak with possible long-term moisture intrusion.

6. Why no response by the NTSB to the June 16, 1997 Airbus internal memo in which Airbus enginer Thomas Thurnagel stated that A300 rudder movements from its left to right limits will produce loads on fin/rear fuselage above ultimate design load. This information was not released to airlines during the four years preceding AA587.

All of this information leads me to believe that the problem or series of problems that brought down flight 587 and took 265 lives have not been properly addressed. This is very disturbing to me as their are stil 47 airlines flying the A300 today. This would not be the first time the NTSB was incorrect in their findings United 811 comes to mind but it makes you wonder why would they ignore this evidence which seems to lead the investigation more to the flight control system of the A300 and specifically the pitch-trim function and rudder interaction. I would like to see this investigation reopened as I feel there is a potentially serious issue unresolved and it could cost the lives of more passengers flying the A300.
 
satx
Posts: 2781
Joined: Mon Apr 11, 2005 7:26 am

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 1:07 pm

Wow. I sure hope you're wrong about this, but my uneducated gut feeling says you might be right.
A300 319 320 321 332 333 388 B727 732 733 735 737 738 739 742 743 744 752 753 763 764 772 77E 77L 773 77W 788 789 C200 700 900 DHC2 DC9 E145 170 175 190 F100 MD81 82 83 87 88 90 | 38 Lines 44 Craft 58 Ports
 
Newark777
Posts: 8283
Joined: Thu Dec 02, 2004 6:23 am

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 1:11 pm

It's always easier to just blame the dead pilot after the fact. As SATX said, I also have that gut feeling that this is the case, and we have fleets of ticking time bombs out there.

Harry
Why grab a Heine when you can grab a Busch?
 
hz747300
Posts: 2420
Joined: Thu Mar 11, 2004 11:38 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 1:14 pm

Have any non-US operators reported the problem or is it just the Yanks? I do remember that Airbus was very defensive after the crash of AA587 and that most people were able to willingly blame the PIC for over-reacting to wake turbulence caused by a departing JAL 747.

Saudi Arabian (then Saudia) operated its A300s all over the Middle East in hot temps. I would be curious to know if they ever reported problems. We had no problems flying the SV A300 between Jeddah - Sanaa and back.
Keep on truckin'...
 
AA767400
Posts: 1897
Joined: Tue Jan 23, 2001 2:04 am

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 2:55 pm

Quoting Coa747 (Thread starter):
3. Under pressure from the pilot union representative at an October 2002 NTSB hearing, the Airbus expert finally admitted that the manufacturer had quietly modified the A300 control system software for passenger comfort following the crash of flight 587. As a result the number of uncommanded rudder incidents subsequently decreased.

Does this mean that airlines now have not experienced as many problems with the rudder?
"The low fares airline."
 
starrion
Posts: 1025
Joined: Sat Jul 19, 2003 1:19 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 3:04 pm

Has any more information regarding the Air Transat A300 the had the rudder disintergrate on departure from Havana been released?
Knowledge Replaces Fear
 
coa747
Topic Author
Posts: 380
Joined: Wed Jul 13, 2005 3:11 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 3:18 pm

The article by Gaillard only discusses incidents by American and FedEx, but I would venture to say that other carriers have had similar issues. I don't have any information on the Air Transat incident but will try to find out. Yes I believe the software modification done by Airbus has resulted in fewer uncommanded rudder incidents which is interesting. Also of note the NTSB did not requesst nor require Airbus to submit earlier software versions for investigation of possible linkage to previous uncommanded rudder problems. While airbus has been an industry leader in fly by wire controls it would seem that these systems had not been perfected in the A300 and leaked over to the A320 as evidence of the Air France crash. Personnally from a safety standpoint I believe the airbus flight management logic places to much emphasis on automated flight control inputs, and does not sufficiently allow for flight crews to over ride the system and that attempts by the crew in an emergency situation to do so may cause unexpected and erratic control reponses by the flight computer.
 
hz747300
Posts: 2420
Joined: Thu Mar 11, 2004 11:38 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 3:27 pm

Quoting Coa747 (Reply 6):
Personnally from a safety standpoint I believe the airbus flight management logic places to much emphasis on automated flight control inputs, and does not sufficiently allow for flight crews to over ride the system and that attempts by the crew in an emergency situation to do so may cause unexpected and erratic control reponses by the flight computer.

This reminds me of the flight computer on the Lunar Shuttle in Airplane II.
Keep on truckin'...
 
777ER
Head Moderator
Posts: 10134
Joined: Fri Dec 19, 2003 5:04 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 3:47 pm

Quoting Coa747 (Thread starter):
and information from Airbus internal testing that proves they were aware of rudder issues prior to the crash of 587.

Airbus knew about this ticking time bomb. Correct me if I'm wrong but didn't Airbus blame AA for the crash even thou Airbus knew about the rudder problems?
Head Forum Moderator
[email protected]
Flown: 1900D,S340,Q300,AT72-5/6,DC3,CR2/7,E145,E70/75/90,A319/20/21,A332/3,A359,A380,F100,B717,B733/4/8/9,B742/4,B752/3,B763,B772/3, B789
With: NZ,SJ,QF,JQ,EK,VA,AA,UA,DL,FL,AC,FJ,SQ,TG,PR
 
NAV20
Posts: 8453
Joined: Thu Nov 27, 2003 3:25 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 3:48 pm

I entirely share the 'gut feeling' about the flight control systems on these aircraft.

The Air Transat thing moves the issue to a different level, since the entire rudder broke off while the aeroplane was cruising on autopilot at 35,000 feet. So it cannot have been 'pilot error'; the only thing that should have been moving the rudder was the yaw damper.

http://www.findarticles.com/p/articl...0UBT/is_2005_March_21/ai_n13458444
"Once you have flown, you will walk the earth with your eyes turned skywards.." - Leonardo da Vinci
 
coa747
Topic Author
Posts: 380
Joined: Wed Jul 13, 2005 3:11 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 4:32 pm

A great movie! I love when they launch the shuttle by jumpstarting it with some old junker. Good stuff. But seriously I'm sure I will get flamed for that last post but I have done a lot of reading on the airbus flight management system. The biggest issue I see with the system is the flight protections built into the logic. The training given to A300 pilots and later A320 pilots during their conversion emphasised the flight protections which the aircraft's computerised control system provides. Airbus conveys that the flight protection regime will prevent the pilot from stalling the aircraft by limiting pitch and roll of the control surfaces so as not to exceed the flight envelope. The problem with this is that it tricks the crew into a false sense of security as they believe the aircaft can not enter into a condition that would cause it to crash. However this logic does not take into account that while the flight regime limits may not be exceeded they still exist. Example of this is the crash of the Air France A320-100 in Mulhouse in 1988. The load factor available at a minimum airspeed is able to sustain only straight and level flight and thus precludes any recovery manoeuvres or turns. The high drag at such low airspeeds, with the aircraft operating on the back side of the power curve, greatly limits any potential climb gradient because of the little available excess thrust. Even on the A340 pilots are trained to use the automated flight control system in all phases of operation. The A340 crash in Toronto is another example of over-reliance on the automated flight system. An aircraft entering a terminal area where severe weather is present and windshear both low and high level are possible should not be operated under automated flight conditions period! Airbus dictates that the auto throttle in particular should be engaged at all times during flight. One can see how flying the aircraft under autothrottle into a microburt condition could quickly get you into trouble. Most airline training also dictates that the A320's autoflight system should be engaged at 100 ft. AGL on takeoff and disconnected at 100 ft. AGL on approach also not the best practice in severe weather conditions.
 
coa747
Topic Author
Posts: 380
Joined: Wed Jul 13, 2005 3:11 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 4:39 pm

Airbus should not have designed the flight control system to allow the rudder to be overtraveled during flight causing it to exceed its maximum design loads and fail. Yes Airbus as I have stated above did know of this flaw in its flight management software before the 587 crash. I believe the Boeing system progressivley limits the deflection of the rudder as speed increases. Therefore jamming the rudder to the floor will not allow it to over travel and cause a structural failure. It would take only seconds for the yaw rate to escalate to the point of structural failure when a rudder fully deflected at altitude. This is perhaps exactly what happened to the Air Transat aircraft.
 
ikramerica
Posts: 15136
Joined: Mon May 23, 2005 9:33 am

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 5:18 pm

Quoting HZ747300 (Reply 7):
This reminds me of the flight computer on the Lunar Shuttle in Airplane II.

Don't you mean the muffler bracket in a 79 Pinto?

As for the Airbus, this is the main concern most have with the fly-by-wire with forced computer interaction design vs. the fly-by-wire with elective computer interaction design. It runs the risk of the computer doing something that shouldn't be done with no way to stop it. Well, you could "blow rock" but, we won't go there.

Danger, Vacuum.
Of all the things to worry about... the Wookie has no pants.
 
kappel
Posts: 1836
Joined: Thu Jul 14, 2005 6:48 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 6:05 pm

Quoting Starrion (Reply 5):
Air Transat A300

Actually, this was an a310

Quoting Coa747 (Reply 6):
While airbus has been an industry leader in fly by wire controls it would seem that these systems had not been perfected in the A300

The a300 is not FBW. IIRC the a320/330/340/380 are FBW, not the a300/310.
It was developed for the a320 and was indeed less the perfect in the beginning. However, I think there haven't been any FBW related crashes after the AF crash.


Quoting Coa747 (Reply 10):
The A340 crash in Toronto is another example of over-reliance on the automated flight system

Don't they have to rely on the automated flight system is such bad weather? Or was the visibility still enough for a visual landing. Or is that not what you mean?
L1011,733,734,73G,738,743,744,752,763,772,77W,DC855,DC863,DC930,DC950,MD11,MD88,306,319,320,321,343,346,ARJ85,CR7,E195
 
GBan
Posts: 488
Joined: Thu Jun 16, 2005 5:10 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 7:48 pm

Quoting Coa747 (Reply 10):
The A340 crash in Toronto is another example of over-reliance on the automated flight system.

Both autopilot and autothrust were disconnected. It was a manual landing. You can find out with very little effort here an A.Net.

Quoting Coa747 (Reply 11):
Airbus should not have designed the flight control system to allow the rudder to be overtraveled during flight causing it to exceed its maximum design loads and fail.



Quoting Coa747 (Reply 6):
Personnally from a safety standpoint I believe the airbus flight management logic places to much emphasis on automated flight control inputs, and does not sufficiently allow for flight crews to over ride the system

So what do you want now?  Wink

Quoting Coa747 (Reply 6):
While airbus has been an industry leader in fly by wire controls it would seem that these systems had not been perfected in the A300 and leaked over to the A320 as evidence of the Air France crash.

The A320 was the first aircraft to have fly by wire. Nothing to "leak over" from the A300.

Quoting Coa747 (Thread starter):
Namely as to captain Sten Molin's excessive control inputs being the cause of this accident. The NTSB for whatever reason did not include in its published findings the following information. Information that revealed a pattern of uncommanded rudder incidents, and information from Airbus internal testing that proves they were aware of rudder issues prior to the crash of 587.

Did you look at the rudder pedal movements in the flight path animation?

http://www.ntsb.gov/events/2001/AA587/flight_path_web01.wmv

I think it is rather obvious that this accident has nothing to do with "uncommanded rudder incidents".
 
Scorpio
Posts: 5050
Joined: Thu Oct 04, 2001 3:48 am

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 8:10 pm

Quoting Kappel (Reply 13):
However, I think there haven't been any FBW related crashes after the AF crash.

The AF crash wasn't FBW related. All the official reports clearly say something different: pilot error, partly due to the pilots not having been briefed correctly about the circumstances of the fly-by, and the trees surrounding the airfield, as well as a last minute change of runways.

It's one of those 'common knowledge' things. Everybody seems to know the plane's FBW was to blame for the crash, except for the people who actually investigated the crash.

Now there will always be people who think they know better than the professional investigators, but I'll stick with the findings of the people who actually do know what they're talking about. The same goes for AA587, especially when the latest round comes from someone who claims the FBW was partly to blame, while the A300 doesn't even have that, and who blames the recent A340 accident on automation without the investigators ever even having mentioned that. When I read that kind of thing, I feel the urge to borrow ANCflyer's  redflag 
 
NAV20
Posts: 8453
Joined: Thu Nov 27, 2003 3:25 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 9:02 pm

The problem was not FBW but the use of 'variable stop' rudder controls. Unlike the 'variable ratio' ones used by other manufacturers, the variable stop ones mean that the rudder pedals require LESS pressure to produce a given rudder movement as speed increases. This is the direct opposite of normal 'feel' (imagine it being easier to turn the steering-wheel of a car at 100kph than it is at 10).

The summary findings of the NTSB were:-

"The National Transportation Safety Board determines that the probable cause of this accident was the in-flight separation of the vertical stabilizer as a result of the loads beyond ultimate design that were created by the first officer’s unnecessary and excessive rudder pedal inputs. Contributing to these rudder pedal inputs were characteristics of the Airbus A300-600 rudder system design and elements of the American Airlines Advanced Aircraft Maneuvering Program.

"The safety issues discussed in this report focus on characteristics of the A300-600 rudder control system design, A300-600 rudder pedal inputs at high airspeeds, aircraft-pilot coupling, flight operations at or below an airplane’s design maneuvering speed, and upset recovery training programs. Safety recommendations concerning these issues are addressed to the Federal Aviation Administration and the Direction Général de l’Aviation Civile."


If anyone wants to read the full NTSB Report on AA587 they can find it here (third one down):-

http://www.ntsb.gov/Publictn/A_Acc1.htm
"Once you have flown, you will walk the earth with your eyes turned skywards.." - Leonardo da Vinci
 
widebody
Posts: 1107
Joined: Wed Aug 02, 2000 5:08 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 9:27 pm

I'll put my faith in the people employed to do the investigation. While interesting Coa747, your posts contain numerous errors about the aircraft and the system. Thousands upon thousands of hours of investigation and examination by propfessionals does it for me. As Nav20 posted, the NTSB findings are available and the investigation is closed. Airbus gets no favours across the water, if there was something to jump on, it would have been jumped on. This case is closed.

If you would like to get involved in accident investigation in the future, it would be wise to learn to never communicate information that you believe to be correct rather than you know to be correct.



[Edited 2005-08-24 14:29:58]

[Edited 2005-08-24 14:33:09]
 
User avatar
kc135topboom
Posts: 11208
Joined: Sun Jan 30, 2005 2:26 am

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 9:56 pm

What has not been publishised to much was the US State Department wanted to "review" the initial and final NTSB reports on AA-587 before public release or the public comment hearings. They "reviewed" these reports with the French Government and Airbus. There were additions and deletions made by the State Department's review panel.

State tied the hands of the NTSB. When the, then, SOS Colin Powell found out about what DOS did, he changed the procedures for DOS's involvement with accident and criminal investigations, and removed the buerocrates involved from ever doing this again. This authority was granted to DOS during the Carter Administration.

I cannot answer as to why the NTSB has never re-opened the crash investigation of AA-587 to set the record straight.
 
NAV20
Posts: 8453
Joined: Thu Nov 27, 2003 3:25 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 10:11 pm

Don't get me wrong, Widebody - I think it's a drastic over-simplification to put the whole accident down to 'pilot error'. Like most accidents, it was a combination of circumstances - and there simply isn't enough evidence to pin it down to one particular cause.

I think press reports have been particularly unfair to Sten Molin, the First Officer. He was highly experienced and had an 'above average' rating - it's difficult to believe that he would have panicked and misused an aeroplane to the extent of breaking the whole tail assembly off. And the body of the NTSB Report was scathing on the bad 'Aircraft/Pilot Coupling' of the flight controls.

Worth remembering too that if he had been captain, and free to use his own judgment, the accident wouldn't have occurred. From the CVR transcript, he was clearly unhappy about the lack of separation between his own aircraft and the earlier departure, which had taken off only moments before, and queried it with the Captain ("You happy with that distance?"}. The Captain told him to go ahead (HOT-2 is Molin, HOT-1 is the captain):-

TWR Japan Air forty seven heavy, fly the Bridge Cimb, contact New
York departure, good morning.
0913:10
JAL47 Bridge Climb, switch to departure, Japan Air four seven, good
morning.
0913:21
HOT-1 you have the airplane.
23 of 28
INTRA-COCKPIT COMMUNICATION AIR-GROUND COMMUNICATION
TIME & TIME &
SOURCE CONTENT SOURCE CONTENT
DCA02MA001
0913:21
HOT-2 I got the brakes.
0913:22
HOT-1 I have the radios.
0913:27.6
TWR American five eight seven heavy, wind three zero zero at
niner, runway three one left, cleared for takeoff.
0913:31.7
RDO-1 cleared for takeoff, American ah, five eight seven heavy.
0913:35.3
HOT-2 you happy with that distance?
0913:38.5
HOT-1 aah, he's.... we'll be all right once we get rollin'. he's supposed
to be five miles by the time we're airborne, that's the
idea.
0913:45.5
HOT-2 so you're happy. lights?
0913:47.1
HOT-1 yeah, lights are on.


http://www.airdisaster.com/forums/archive/index.php/t-53262.html
"Once you have flown, you will walk the earth with your eyes turned skywards.." - Leonardo da Vinci
 
User avatar
Starlionblue
Posts: 20650
Joined: Fri Feb 27, 2004 9:54 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 10:32 pm

Quoting Coa747 (Reply 6):
Personnally from a safety standpoint I believe the airbus flight management logic places to much emphasis on automated flight control inputs, and does not sufficiently allow for flight crews to over ride the system and that attempts by the crew in an emergency situation to do so may cause unexpected and erratic control reponses by the flight computer.

1. The A300 does not have the "Airbus flight management logic". There is no computer between the pedals and the rudder.
2. The yaw damper controls the rudder on any airliner in most cases.
3. Most pilots will tell you not to touch the rudder on a jetliner except in an engine out situation or when landing in a crosswind.

Quoting Coa747 (Reply 10):
The problem with this is that it tricks the crew into a false sense of security as they believe the aircaft can not enter into a condition that would cause it to crash. However this logic does not take into account that while the flight regime limits may not be exceeded they still exist. Example of this is the crash of the Air France A320-100 in Mulhouse in 1988. The load factor available at a minimum airspeed is able to sustain only straight and level flight and thus precludes any recovery manoeuvres or turns. The high drag at such low airspeeds, with the aircraft operating on the back side of the power curve, greatly limits any potential climb gradient because of the little available excess thrust.

I agree about the false sense of security. Airbus training has come a long way since that crash.

If you had flown a 737 into a similar situation, it would most likely had stalled. The 320 did not stall, but flew in a controlled fashion into the trees. Unless you had mounted the Shuttle SRBs under the wings, there was no way that plane was coming out of the corner the pilot had flown it into.

If the pilot chooses to fly at stall speed and decreasing, while altitude is decreasing, at a low power setting, under the level of surrounding trees, he's not "using his superior skills to stay out of situations where he might need to use them". This is valid on ANY aircraft.

Quoting Coa747 (Reply 11):
Airbus should not have designed the flight control system to allow the rudder to be overtraveled during flight causing it to exceed its maximum design loads and fail

It's possible to break the control surfaces of ANY airliner with inputs, except Airbi with envelope protection in normal law. While the A300 rudder was found to be "oversensitive", meaning it was "too easy" to break it with controls, the fact of being able to break the plane is just a fact of life. A 767 pilot (or a Cessna 172 pilot) would have no problem breaking the plane with control inputs.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
kappel
Posts: 1836
Joined: Thu Jul 14, 2005 6:48 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 10:33 pm

Quoting NAV20 (Reply 19):
Worth remembering too that if he had been captain, and free to use his own judgment, the accident wouldn't have occurred.

Kinda reminds me of the 1977 KLM-Pan AM accident at Tenerife. There also the FO questioned the captain and was ingnored. It's sad to see that such a minor thing as waiting a few seconds could have prevented this disaster.
L1011,733,734,73G,738,743,744,752,763,772,77W,DC855,DC863,DC930,DC950,MD11,MD88,306,319,320,321,343,346,ARJ85,CR7,E195
 
777236ER
Posts: 12213
Joined: Sat Aug 18, 2001 7:10 am

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 10:36 pm

Gee, you don't think the AA pilots have an agenda?

The DFDR recorded not only rudder travel, but pedal deflection. The roll inputs by the PF were almost directly linked with the pedal inputs - there was no response delay associated with the PF responding to uncommanded inputs. The PF made the severe rudder reversals, there was no uncommanded movement.

The evidence shows that the crash was primarily due to pilot error caused by poor training, end of story. A300 systems may have not been the most appropriate, but they didn't lead to the crash. Nor would a different system have prevented it. If you take a 767 and perform 3 pedal stop-to-pedal stop rudder reversals at 300 knots, you'll likely end up with similar damage.
Your bone's got a little machine
 
User avatar
Starlionblue
Posts: 20650
Joined: Fri Feb 27, 2004 9:54 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 10:46 pm

Quoting 777236ER (Reply 22):
If you take a 767 and perform 3 pedal stop-to-pedal stop rudder reversals at 300 knots, you'll likely end up with similar damage.

Or any kind of airliner, for that matter. FAA certification regs specify that the rudder should hold for one deflection to the stops and back to center. By doing it three times, the structure didn't have time to dissipate the loads.

And oh by the way, the A300 rudder structure exceeded FAA/JAA specs when it came to the pertinent loads.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
FinnWings
Posts: 633
Joined: Fri Oct 24, 2003 6:03 am

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 10:47 pm

Quoting Coa747 (Thread starter):
6. Why no response by the NTSB to the June 16, 1997 Airbus internal memo in which Airbus enginer Thomas Thurnagel stated that A300 rudder movements from its left to right limits will produce loads on fin/rear fuselage above ultimate design load. This information was not released to airlines during the four years preceding AA587.

The answer for this is very simple. The ultimate design load will be exceeded in every single aircraft in the world when making full rudder deflection from the full right to full left fastly enough. The manufacturers only guarantee that rudder is capable to handle abrupt movement from center position to left (or right) and back but NOT center-left-right-center movement!! This is the case even below Va (Design maneuvering speed)... So there is nothing special with the statement of Mr. Thurnagel.

Secondly, I don't know why the pilot tried to recover from extensive roll movement using primarily rudder!? This is definitely against the basic handling procedures of any aircraft...

Quoting Coa747 (Reply 11):
Airbus should not have designed the flight control system to allow the rudder to be overtraveled during flight causing it to exceed its maximum design loads and fail.

Could you please tell me at least one aircraft from 80s or before where such a control system is developed which would prevent overtraveling? ATRs, B727s, B737 classics, MDs.... you can exceed the design loads of rudder in all of those. Such designs were not available in any commercial aircraft at that time when A300 was designed.

Best Regards,
FinnWings
 
NAV20
Posts: 8453
Joined: Thu Nov 27, 2003 3:25 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 10:47 pm

Quoting Starlionblue (Reply 20):
The 320 did not stall, but flew in a controlled fashion into the trees.

Not quite, Starlionblue - the FBW systems put the aeroplane into 'landing mode' once it was below 50' RA, and 'landed' it automatically. This was eventually admitted in a press interview by no less than John Lauber, Airbus VP in charge of Safety Engineering:-

"Lauber said the pilots were supposed to fly by with the gear down at about 100 feet. Instead, they came in at less than 30 feet off the ground. When the plane gets below 50 feet, the computer assumes the pilots are trying to land, Lauber said.

"The fact is, the plane did exactly what it was supposed to do," he said. Only it landed in the tress.

"Airbus learned much from that incident, Lauber said.

"Until the crash, he said, there was a "genuine psychology" around Airbus that it had designed a crash-proof airplane because of the hard protections.

"The repercussions from that accident continue to reverberate," Lauber acknowledged."


http://seattlepi.nwsource.com/business/boe202.shtml
"Once you have flown, you will walk the earth with your eyes turned skywards.." - Leonardo da Vinci
 
CHRISBA777ER
Posts: 3715
Joined: Thu Mar 01, 2001 12:12 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 10:58 pm

The A300 is totally unsafe and Airbus knew about it the whole time - but they place their profits over the lives of the passengers who fly their deathtrap planes. I'm refusing to fly on any Airbus from now on.

Its Boeing all the way for me.
What do you mean you dont have any bourbon? Do you know how far it is to Houston? What kind of airline is this???
 
777236ER
Posts: 12213
Joined: Sat Aug 18, 2001 7:10 am

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 11:14 pm

Quoting NAV20 (Reply 25):
Not quite, Starlionblue - the FBW systems put the aeroplane into 'landing mode' once it was below 50' RA, and 'landed' it automatically.

The entire event was disputed from start to finish.

The run was supposed to be carried out at 100ft, it was carried out at 30ft. The commander was sure his altimeter said 100ft, and given OEB 06/2: Baro-Setting Cross Check stated that the A320 altimeter had sometimes read the wrong altitude at some barometric settings, this shouldn't have been ignored (yet was by the investigation).

Despite TOGA application quite a time for the impact (although not long enough before, according to the report), the engines had only reached 83% N1 at time of impact. A potential reason for this was stated in OEB 19/1: Engine Acceleration Deficiency at Low Altitude.

Both these Operational Engineering Bulletins were received by AF a month before the crash, but were not distributed until after the crash.

Both data recorders were illegally taken by the French aviation authority and held for 10 days, which was itself against the law. They were both opened and tampered with. Eight seconds of tape was removed and the CVR and DFDR were 4 seconds out of sync at the time of impact, leading to allegations of significant tampering.

Given this, and the fact that the commender spent 6 months in prison (!) for manslaughter, I think it's fair to say the final report wasn't accurate in its account.

That being said, it had no bearing whatsoever on AA587.
Your bone's got a little machine
 
NAV20
Posts: 8453
Joined: Thu Nov 27, 2003 3:25 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 11:20 pm

Quoting FinnWings (Reply 24):
Secondly, I don't know why the pilot tried to recover from extensive roll movement using primarily rudder!? This is definitely against the basic handling procedures of any aircraft...

Not at all sure about that, FinnWings.

The problem would have been the bank angle, not the actual roll. Plus the fact that he was only at about 2,000 feet and being thrown about, and couldn't afford to lose any height.

If you've flown, you'll know that the basic principle in a bank is to keep the nose level with the horizon. Given that, in a bank, both the elevators and the rudder are acting at an angle to the vertical, it would be instinctive for any pilot to make coordinated use of both elevators and rudder, as necessary, to hold the nose up; while also using the ailerons to level the wings.
"Once you have flown, you will walk the earth with your eyes turned skywards.." - Leonardo da Vinci
 
Scorpio
Posts: 5050
Joined: Thu Oct 04, 2001 3:48 am

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 11:28 pm

Quoting CHRISBA777ER (Reply 26):
The A300 is totally unsafe and Airbus knew about it the whole time - but they place their profits over the lives of the passengers who fly their deathtrap planes. I'm refusing to fly on any Airbus from now on.

Please tell me that was sarcastic.
 
Udo
Posts: 4288
Joined: Tue May 18, 1999 5:16 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 11:33 pm

Quoting CHRISBA777ER (Reply 26):
The A300 is totally unsafe and Airbus knew about it the whole time - but they place their profits over the lives of the passengers who fly their deathtrap planes. I'm refusing to fly on any Airbus from now on.

Good! Makes one paranoid passenger less on Airbus flights. Big grin


Regards
Udo
Me & You & a Plane Named Blue...
 
CHRISBA777ER
Posts: 3715
Joined: Thu Mar 01, 2001 12:12 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 11:46 pm

Quoting Scorpio (Reply 29):
Quoting CHRISBA777ER (Reply 26):
The A300 is totally unsafe and Airbus knew about it the whole time - but they place their profits over the lives of the passengers who fly their deathtrap planes. I'm refusing to fly on any Airbus from now on.

Please tell me that was sarcastic.

 Smile
What do you mean you dont have any bourbon? Do you know how far it is to Houston? What kind of airline is this???
 
coa747
Topic Author
Posts: 380
Joined: Wed Jul 13, 2005 3:11 pm

RE: American Airlines 587 A Closer Look

Wed Aug 24, 2005 11:50 pm

You can flame me all you want. I have nothing against Airbus or Boeing. I do however have an issue with an investigative board not following all possible leads. You can not tell me that flight control issues on the A300 were not serious before the 587 crash as I have proved their were. Also I was not meaning to imply that the A300 had fly by wire controls but the flight management system was in place and used as a model for the A320 and later models. My point being the logic this system is developed around and the way Airbus instructs airlines to train its pilots leads to issues. You shold not have blind faith in any aircraft system and the automatic protection envelope gives some pilots that feeling. Furthermore the airbus flight management system can in some instances over-ride pilots inputs which itself can be an issue. Last don't tell me that NTSB is always right. United 811 showed us they are not. The only reason they amended their intial report was because Lee Campbell's mother and father launched their own independent investigation and over the course of years of hard work and determination proved that electrical shorts could cause the cargo door to open on 747's. If not for the Campbell's hard work and determination this could still be an issue today.

Please do not post in the topic if you have nothing valuable to add. Go wage your A vs. B wars somewhere else. I developed this topic to discuss the incident at hand and the investigation from a technical side and nothing more.
 
CHRISBA777ER
Posts: 3715
Joined: Thu Mar 01, 2001 12:12 pm

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:05 am

Actually COA747 apologies - you are right - my input to this thread hasnt really been particularly constructive. I'm just a bit sick of being told that something is not safe or not as good or whatever just because it isnt American - its boring.

For the record, and feel free to call me naive or whatever, but i think that if the relevant Government investigation boards find there to have been wrongdoing on the part of Airbus (and God knows that would be a VERY popular thing to say over there and carry A LOT of political water) - they would have said it. I imagine there would have been some pressure from a number of quarters to say just that - If Airbus A300s really were unsafe then they would say so. At the very least you'd see Airbus grounding all for full checks to maintain due diligence for the inevitable legal process.

It hasnt happened and for me, thats good enough.

Why dont the A300s fall out of the sky all the time then?

Its already been suggested that the 767 is similarly inhibited - how come they are not falling out of the sky either?

I just think its scaremongering by some - taken up by people like yourself who DONT have a political or nationalistic agenda and unfortunately your findings (which appear well researched and presented - well done) are tainted with the same agenda as your peers.

Its a shame - but however many people like you are trying to actually make an informed point, there are ten others who echo the smug sentiments in my first post above. I've struggled with this over the years - have given up even talking to most people on here - its pointless i'm afraid.

[Edited 2005-08-24 17:06:02]
What do you mean you dont have any bourbon? Do you know how far it is to Houston? What kind of airline is this???
 
777236ER
Posts: 12213
Joined: Sat Aug 18, 2001 7:10 am

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:07 am

Quoting CHRISBA777ER (Reply 33):
Its already been suggested that the 767 is similarly inhibited - how come they are not falling out of the sky either?

No, it's not actually. I believe there is an issue behind the rudder pedal movement, specifically the use of the variable stop system. That being said, this was simply a quirk, and all aircraft have quirks. It was not that in itself which caused the crash. Poor pilot training and ultimately pilot error caused the crash.
Your bone's got a little machine
 
AirRyan
Posts: 2399
Joined: Wed Mar 30, 2005 9:57 am

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:09 am

Quoting SATX (Reply 1):
It's always easier to just blame the dead pilot after the fact.

It's because they can't defend themselves! It's gotten to the point so as to when I read that conclusion I immediately think otherwise! Now I know in most cases pilot error can in one way or another be attributed to class-a mishaps but it seems like it is used far too often and as a crutch for the gov. to satisfy the public and not cause a business to "lose" any more of it.
 
FinnWings
Posts: 633
Joined: Fri Oct 24, 2003 6:03 am

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:17 am

NAV20,

I agree with you, I simplified my earlier reply too much. The coordinated turn is important of course and you will need rudder deflection to recover from banking. This is now pure speculation and I might be far off as I don't know every detail of the accident. However as far as I have understod the pilot tried to recover from banking and roll from side to side several times after hitting the wake turbulence. The correct action would have been use quick rudder deflection to the opposite direction of bank and level the wings using ailerons. This is also what the pilot most likely did which is a correct action and will prevent the developing of spin. As far as I have understood after that things got wrong when the aircraft banked again...

As a result of wake the aircraft banked abruptly again but now to other direction and pilot tried to recover using full rudder deflection again. However the rudder wasn't in neutralized position now due the recovery of previous bank and it moved full scale to the other side causing exceeding of the ultimate load. This maybe happened still a few times causing rudder to rupture.

When aircraft enters severe turbulence or wake the correct action is try to keep wings leveled and hold the nose attitude but DON'T try to keep the altitude. However in this case they had only a few thousand feet so keeping of the altitude was definitely important too. What you shouldn't EVER try to do is manually dampen the movements of the aircraft! One of the basic principles of every commercial aircraft is that they must be stabile in all directions which means that the aircraft will dampen the movement eventually without the pilot input. Now, if the pilot tries too intensively dampen the movements of an aircraft he could actually overstress the aircraft, especially because the reflects of human will always cause some lag to the action.

After the first bank and rudder deflection the pilot of AA587 should have only neutralize the rudder to center position or move it slightly to other direction but definitely not a full movement to opposite direction! At this point the coordinated turn is not important anymore, just keep the altitude, attitude and try keep the wings level, but be extremely cautious with yawing moment and rudder deflections. The extensive yawing is not going to kill you but loss of altitude will and therefore all effort should be put to try keep wings level and nose attitude constant.

Best Regards,
FinnWings

[Edited 2005-08-24 17:22:06]
 
N908AW
Posts: 864
Joined: Thu Aug 11, 2005 1:05 pm

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:18 am

Quoting Kappel (Reply 13):
Actually, this was an a310

Ahha...another defective Airbus.

Quoting CHRISBA777ER (Reply 33):
Its already been suggested that the 767 is similarly inhibited - how come they are not falling out of the sky either?

Source please?

Quoting CHRISBA777ER (Reply 33):
For the record, and feel free to call me naive or whatever, but i think that if the relevant Government investigation boards find there to have been wrongdoing on the part of Airbus (and God knows that would be a VERY popular thing to say over there and carry A LOT of political water) - they would have said it.

Ok. That's pretty naive. The government workers aren't gods; they didn't really know what happened in the pilot's mind. And I do halfway agree that it was the pilot's fault for not knowing how bad the A300 rudder is in the condition he was in. But the crash just can't all be blamed on the pilot.
'Cause you're on ATA again, and on ATA, you're on vacation!
 
redflyer
Posts: 3910
Joined: Thu Feb 24, 2005 3:30 am

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:18 am

Quoting Starlionblue (Reply 20):
A 767 pilot (or a Cessna 172 pilot) would have no problem breaking the plane with control inputs.

Not true, you should not be able to "break" a plane as long as it's speed is maintained below Va (design maneuvering speed). And I think one of the reasons the NTSB took a keen look at this incident is because all pilots are taught from early on that abrupt maneuvers will not over-stress an airplane as long as it's speed is below Va. Obviously, AA587 proved that airplanes can "break" even if they are well under Va.

Quoting FinnWings (Reply 24):
Secondly, I don't know why the pilot tried to recover from extensive roll movement using primarily rudder!? This is definitely against the basic handling procedures of any aircraft...


But it wasn't against the operating procedures specified by AA in their pilot training curriculum. I think this factor alone was the primary reason most of the blame was laid at AA's feet.
A government big enough to take away a constitutionally guaranteed right is a government big enough to take away any guaranteed right. A government big enough to give you everything you need is a government big enough to take away everything you have.
 
coa747
Topic Author
Posts: 380
Joined: Wed Jul 13, 2005 3:11 pm

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:20 am

I do not claim to be an expert. I simply believe that you must take everything you here with a grain of salt. I have no problem with others debating the points I have raised. This was the point of the topic. I do however know enough to realize that no accident is caused by an single one action. To call American 587 a simple case of pilot error is to do a great disservice to all who lost their lives. Did American's pilot training leave something to be desired? Absolutely. I am not arguing that here because I believe we all agree on this. I would simply like to have seen the board investigate all angles before issuing its report. The case of US Air 427 is a model for how an investigation should be handled. I firmly believe that flight control issues existed on the A300 regarding the rudder and Airbus was aware of these issues and did not alert airlines. Did this issue cause the accident outright. No, but could it have been a contributing factor I believe so. Was any of this considered by the NTSB not necessarily.
 
777236ER
Posts: 12213
Joined: Sat Aug 18, 2001 7:10 am

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:21 am

Quoting RedFlyer (Reply 38):
Not true, you should not be able to "break" a plane as long as it's speed is maintained below Va (design maneuvering speed).

Sorry, wrong. Manoeuvring speed is for manoeuvres (surprisingly), not multiple and complete control surface movement. The A300-600R is completely within all regulations, despite quirky rudder pedal behaviour. And that's all it is.
Your bone's got a little machine
 
NAV20
Posts: 8453
Joined: Thu Nov 27, 2003 3:25 pm

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:26 am

Quoting 777236ER (Reply 34):
I believe there is an issue behind the rudder pedal movement, specifically the use of the variable stop system. That being said, this was simply a quirk, and all aircraft have quirks.

With respect, I believe that it is more than a 'quirk'. As I mentioned, it produces rudder 'feel' that is the direct opposite of what all pilots will have grown used to from their first flying lesson. I know Airbus and MD have both used them in the past, and from the comments above it appears that Boeing also used them on the 767.

All I hope is that, given the lessons of AA587, NONE of the manufacturers use them now, and all aeroplane designs have reverted to 'variable ratio'.
"Once you have flown, you will walk the earth with your eyes turned skywards.." - Leonardo da Vinci
 
FinnWings
Posts: 633
Joined: Fri Oct 24, 2003 6:03 am

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:36 am

Quoting RedFlyer (Reply 38):
all pilots are taught from early on that abrupt maneuvers will not over-stress an airplane as long as it's speed is below Va.

Yes, and unfortunately almost all pilots are taught wrong with this issue, including me during my PPL. This is one of the biggest misconceptions among the pilots. When you'll take a close look of FARs or JARs they don't say anything that the control surfaces should be able to withstand abrupt full scale movement from left to right or up and down even below Va. However they MUST be able to handle the loads which are caused from neutral to full deflection to other direction and back to NEUTRAL position only.

Quoting RedFlyer (Reply 38):
But it wasn't against the operating procedures specified by AA in their pilot training curriculum. I think this factor alone was the primary reason most of the blame was laid at AA's feet.

You are correct, indeed. The pilots most likely did only what where taught and therefore we should take a closer look of the organization who trained them which in this case is AA.

Best Regards,
FinnWings



[Edited 2005-08-24 17:41:25]
 
redflyer
Posts: 3910
Joined: Thu Feb 24, 2005 3:30 am

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:38 am

Quoting 777236ER (Reply 40):
Sorry, wrong. Manoeuvring speed is for manoeuvres (surprisingly), not multiple and complete control surface movement.

Sorry, wrong. Va, which goes down as a plane's weight goes down, represents the maximum speed at which you can use FULL, ABRUPT control movement without stressing the airframe.

This goes to the heart of the issue surrounding AA587 because, as I said previously, all pilots are taught that abrupt control movements will not break an airframe as long as the speed is below Va. Hence, the inordinate amount of time the NTSB spent inspecting the recovered pieces of wreckage trying to determine if there was existing damage to the rudder prior to the flight. When no prior damage was found, they were left to assume that Va is in fact not necessarily a limiting speed, certainly not where a 300 and like aircraft are concerned.
A government big enough to take away a constitutionally guaranteed right is a government big enough to take away any guaranteed right. A government big enough to give you everything you need is a government big enough to take away everything you have.
 
widebody
Posts: 1107
Joined: Wed Aug 02, 2000 5:08 pm

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:45 am

It's not called flaming when somebody points out the inaccuracies in your postings or disagrees with your opinions COA747. In reply 32 you mention that you have 'proven' serious issues with the Airbus flight control system, but in reply 39 you mention that you are not an expert. If the real experts could not prove it, then you haven't proven it, especially with the wishy-washy info in the 1st post. In reply 39 you mention "to call American 587 a simple case of pilot error is to do a great disservice to all who lost their lives" - the NTSB report doesn't say this, and from I can read in this thread, you are the only one who has said this so far. Just stop quoting opinion as fact.

[Edited 2005-08-24 17:46:07]
 
Scorpio
Posts: 5050
Joined: Thu Oct 04, 2001 3:48 am

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 12:53 am

Quoting RedFlyer (Reply 43):
Sorry, wrong. Va, which goes down as a plane's weight goes down, represents the maximum speed at which you can use FULL, ABRUPT control movement without stressing the airframe.

Yes. Once. Not repeatedly as happened on AA587. Finnwings stated it correctly in reply 42:

Quoting FinnWings (Reply 42):
However they MUST be able to handle the loads which are caused from neutral to full deflection to other direction and back to NEUTRAL position only.

As in, not full deflection to full deflection to full deflection, x2 as what happened here.
 
coa747
Topic Author
Posts: 380
Joined: Wed Jul 13, 2005 3:11 pm

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 1:02 am

Perhaps prove is the wrong word. These incidents raise concern and certainly prove that serious incidents of uncommanded rudder movements did occur. So we can not infer automatically that the pilot was soley responsible for this accident. I am however stating that I do not believe the board fully investigated these avenues. The FedEx delamination discovery should have in itself caused serious concern. When I refered to people flaming me it was in response to those that seemed to think the NTSB could not possibly be wrong in their findings. I gave United 811 as an example of this. The fact is that they are a government agency and as such are subject to influence. Also my point about this investigation being reopened is directly related to the unresolved questions of the A300 uncommanded rudder incidents. Show me where the incidents in the 68+ page report were investigated and I will be satisfied. Some do not seem to understand how the system works here in the US. The NTSB investigates accidents and makes safety recommendations but does not have the authority to implement them. It is the FAA’s job to review an implement the safety recommendations as they see necessary. If the NTSB does not present a complete picture to the FAA then how can it be expected to act in an appropriate manner? That is the ultimate point why haven’t these incidents been investigated and how can a determination be made as to their role in a crash without investigating them. Reminds me of the 737 rudder issue and the pilot reports that were largely ignored as anomalies until the US Air accident.
 
User avatar
Starlionblue
Posts: 20650
Joined: Fri Feb 27, 2004 9:54 pm

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 1:28 am

Quoting NAV20 (Reply 25):
Quoting Starlionblue (Reply 20):
The 320 did not stall, but flew in a controlled fashion into the trees.

Not quite, Starlionblue - the FBW systems put the aeroplane into 'landing mode' once it was below 50' RA, and 'landed' it automatically. This was eventually admitted in a press interview by no less than John Lauber, Airbus VP in charge of Safety Engineering:-

"Lauber said the pilots were supposed to fly by with the gear down at about 100 feet. Instead, they came in at less than 30 feet off the ground. When the plane gets below 50 feet, the computer assumes the pilots are trying to land, Lauber said.

"The fact is, the plane did exactly what it was supposed to do," he said. Only it landed in the tress.

The plane did, in fact, perform as it should have. The pilot left something to be desired. NAV20 is correct in the particulars. But the plane did not stall.

Quoting CHRISBA777ER (Reply 26):
The A300 is totally unsafe and Airbus knew about it the whole time - but they place their profits over the lives of the passengers who fly their deathtrap planes. I'm refusing to fly on any Airbus from now on.

Its Boeing all the way for me.

I wish I could put in a raspberry sound right now... But hey, dibs on the free seat.

Quoting Coa747 (Reply 32):
. Also I was not meaning to imply that the A300 had fly by wire controls but the flight management system was in place and used as a model for the A320 and later models.

Hmmm some stuff was used. But there is no flight management system on the A300 as on the A320 etc. No integrated system that translates commands from the cockpit to the surfaces.

Quoting Coa747 (Reply 32):
Furthermore the airbus flight management system can in some instances over-ride pilots inputs which itself can be an issue.

Of course, but since such a system is not in place on the A300 the point is moot.

Quoting FinnWings (Reply 36):
What you shouldn't EVER try to do is manually dampen the movements of the aircraft! One of the basic principles of every commercial aircraft is that they must be stabile in all directions which means that the aircraft will dampen the movement eventually without the pilot input. ...
...
After the first bank and rudder deflection the pilot of AA587 should have only neutralize the rudder to center position or move it slightly to other direction but definitely not a full movement to opposite direction!

Not on most military jets either. Both Gripen and F-22 have been broken by pilots who tried to compensate manually. This is known as Pilot Induced Oscillation.

Quoting RedFlyer (Reply 38):
Quoting Starlionblue (Reply 20):
A 767 pilot (or a Cessna 172 pilot) would have no problem breaking the plane with control inputs.

Not true, you should not be able to "break" a plane as long as it's speed is maintained below Va (design maneuvering speed). And I think one of the reasons the NTSB took a keen look at this incident is because all pilots are taught from early on that abrupt maneuvers will not over-stress an airplane as long as it's speed is below Va. Obviously, AA587 proved that airplanes can "break" even if they are well under Va.

You can break a plane at speeds below Va with control inputs.

Quoting Coa747 (Reply 39):
To call American 587 a simple case of pilot error is to do a great disservice to all who lost their lives

Of course. And the NTSB did not call it a simple case of pilot error. Training of AA pilots and design of the A300 were both cited as contributory causes.

Quoting RedFlyer (Reply 43):
Quoting 777236ER (Reply 40):
Sorry, wrong. Manoeuvring speed is for manoeuvres (surprisingly), not multiple and complete control surface movement.

Sorry, wrong. Va, which goes down as a plane's weight goes down, represents the maximum speed at which you can use FULL, ABRUPT control movement without stressing the airframe.

Yes, you can make full, abrupt movements without BREAKING the airframe, but I guarantee you it will be STRESSED. But you can break a plane at speeds below Va with control inputs. Just make repeated inputs to the stops in opposite directions. It's that simple.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
User avatar
777wt
Posts: 828
Joined: Wed Jan 19, 2005 7:45 am

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 1:30 am

In a report related to this, they showed an image of the AA's A300 rudder which has a layer of composite or metal added to both sides of it and, holes were drilled and multiple bolts were installed.

This was traced back to the building of the AA's A300. In the hanger, there was a storm outside and the plane's tail hit the ground during the storm. Airbus looked at the rudder and saw damage, they decided to fix it instead of replacing the whole thing.

They didn't put it in the log and didn't tell AA about this. Surely AA would have rejected the aircraft if they did tell them.

That's one thing should be looked at too.
 
NAV20
Posts: 8453
Joined: Thu Nov 27, 2003 3:25 pm

RE: American Airlines 587 A Closer Look

Thu Aug 25, 2005 1:31 am

Quoting FinnWings (Reply 36):
I agree with you, I simplified my earlier reply too much.

No problem, FinnWings, glad you realised that I wasn't just contradicting you for its own sake. Nice to talk to someone else who can imagine what it might be like to be at the control of a big airliner that is being thrown into 20+-degree banks in both directions at only 2,000 feet.....

Can't answer all the questions you raise in a short post, but I'd urge you to read the full NTSB Report; I put a link on above, if you can't find it I'll happily repost it.

After reading it, three main areas of doubt remain in my mind:-

1. There were two wake episodes. In the first, the rudder scarcely moved at all; such movement as did occur was within the range (1-2 degrees) that could have been applied by the yaw damper, which was engaged. In the second, there were quite big rudder movements (although the recorded pedal movements were only of the order of 1-2 inches). It doesn't make sense to me that the same pilot would use the rudder minimally, or not at all, in the first incident; but suddenly start using it wildly (if pressing the pedals up to 2 inches can be called 'wildly') in the second.

2. The NTSB were reconstructing the event from limited data contained in the Flight Data Recorder. The whole thing happened very quickly, and they were unable completely to reconcile the times of the FDR with the bangs and thumps recorded by the Cockpit Voice Recorder. So it is an open question whether the rudder movements occurred before or AFTER the tail began breaking off. In addition, and maybe more important, the conclusion that the pilot moved the pedals and the pedals moved the rudder appears to be a 'conclusion' only. Given the 'feedback' built into the systems, it seems at least equally possible that the rudder, 'fluttering' as the hinges gave and it began to break off, moved the PEDALS.

3. That the A300 had some sort of rudder problem had been known about for a number of years, from previous reports of 'uncommanded rudder movements'. Airbus had written to the airlines advising them to train their pilots not to use the rudder 'abruptly' to counteract turbulence. American Airlines admitted that they had - but said that they had never indicated the level of risk (i.e. complete structural failure) that that practice might involve. Personally I would like to know why Airbus appears to have contented itself with writing letters, rather than commissioning a full review of the rudder design and its control systems. To my mind, given the recent Air Transat case in which the rudder parted company even though the autopilot was flying the aeroplane, that question remains very much 'on the table'. Especially since the A330, apparently, has a very similar rudder design and is included in the recent round of 'inspections' that have been ordered.
"Once you have flown, you will walk the earth with your eyes turned skywards.." - Leonardo da Vinci

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos