"USA Today" article about A-300 rudder problems?
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I still hark back to the rather spectacular losses that Boeing have had, the findings put forth by the NTSB and the total reluctance of Boeing to do anything that might upset their little corner in aviation. Did we see a front page article about the sh*t fights the NTSB had while trying to get Boeing to do some kind of fix of their 737, no we didn't. After the loss of two aircraft they still refused to believe the yaw was uncommanded. What about the grounding of the 747 while the centre tank was sorted? Airbus gets slammed because a crew stopped minding their shop and threw in rudder at the onset of a stall? What were they using for a brain?
Thread Starter
As for our "friends" at the FAA, were they not accused of practically hiding info from European sources regarding the serious problems suffered by the ATR-42 turboprop in moderate-severe icing conditions?
The point here is not where any plane is built-but can't regulatory authorities (at least in the US) "delay" notifying domestic airlines about whatever an aircraft problem consists of, as long as their documents are complete (in a legal sense), being unwilling to acknowledge problems with their certification conditions? Other than fatal accidents reported US media, which often include only the large aircraft in other countries with many people who perish onboard and/or on the ground. We seem to never read about incidents with foreign aircraft. Without "enlightenment" from the attorneys and papercrats who run our FAA, how would the American public even know about a plane which almost crashes in the Italian Alps (except for the rare bird on Pprune)? The FAA seems to be as motivated in this area as the Church bishops were in 655 AD to preserve Roman literature which explained how to cook garum pizza (with figs) for a party of twenty.
A tragedy occured in Indiana, allegedly because of the lack of initiative, or attempt to bury the info about aileron "snatch", if the term is correct. After the dead had been buried, our "Tombstone Agency" initiated more testing behind a water-spraying KC-135 and the manufacturer redesigned/enlarged the boots on the upper wing.
The point here is not where any plane is built-but can't regulatory authorities (at least in the US) "delay" notifying domestic airlines about whatever an aircraft problem consists of, as long as their documents are complete (in a legal sense), being unwilling to acknowledge problems with their certification conditions? Other than fatal accidents reported US media, which often include only the large aircraft in other countries with many people who perish onboard and/or on the ground. We seem to never read about incidents with foreign aircraft. Without "enlightenment" from the attorneys and papercrats who run our FAA, how would the American public even know about a plane which almost crashes in the Italian Alps (except for the rare bird on Pprune)? The FAA seems to be as motivated in this area as the Church bishops were in 655 AD to preserve Roman literature which explained how to cook garum pizza (with figs) for a party of twenty.
A tragedy occured in Indiana, allegedly because of the lack of initiative, or attempt to bury the info about aileron "snatch", if the term is correct. After the dead had been buried, our "Tombstone Agency" initiated more testing behind a water-spraying KC-135 and the manufacturer redesigned/enlarged the boots on the upper wing.
Last edited by Ignition Override; 29th May 2003 at 14:32.
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bluskis
If one limited the rudder authority to the extent that structural failure was impossible, then there would be insufficient rudder to control the aeroplane should an engine fail. There would be insufficient rudder to control the aeroplane during crosswind landings, unless the crosswind limits were reduced.
To employ your proposed solution would see aircraft failing certification in the single engine case, and a proportion of the then virtual reality flights cancelled due to excessive crosswind.
If one strengthened the rudder such that it could withstand any pilot induced loads, then one would be adding considerable mass at the rear of the aeroplane. For the aeroplane to then be stable, there would need to be an even more massive increase in weight at the front of the aero-plane. There would be a knock on effect, spiraling a massive weight increase. Fuel consumption would escalate and your ticket price would follow suit.
Then, don't forget, there's the wings - the elevator will allow a pilot to puill the wings off ! Shock horror ! Lets reduce elevator authority to prevent that -- OOPS ! Not enough elevator authority to control the aeroplane ! Lets strengthen the wings - impossible weight and cost spiral.
Then there's the undercarriage - that could be wiped off by a really rough landing ! Lets strengthen that ! Dohhh ! ..............
I think that by that stage in the "redesign" we've grounded the aeroplane ! It won't fly properly or safely now and it's too heavy for it's twelve (I guess) engines to push it into the air.
BTW, bluskis, falling (eventually) into the trap of arguing my engine revs analogy, you do know that commercial jet engines can be damaged by incorrect pilot handling, don't you ?
If a car engine is liable to disintegrate above an rpm which it is infact capable of reaching, the normal practice is to limit the engine so that it cannot reach said revs.
To employ your proposed solution would see aircraft failing certification in the single engine case, and a proportion of the then virtual reality flights cancelled due to excessive crosswind.
If one strengthened the rudder such that it could withstand any pilot induced loads, then one would be adding considerable mass at the rear of the aeroplane. For the aeroplane to then be stable, there would need to be an even more massive increase in weight at the front of the aero-plane. There would be a knock on effect, spiraling a massive weight increase. Fuel consumption would escalate and your ticket price would follow suit.
Then, don't forget, there's the wings - the elevator will allow a pilot to puill the wings off ! Shock horror ! Lets reduce elevator authority to prevent that -- OOPS ! Not enough elevator authority to control the aeroplane ! Lets strengthen the wings - impossible weight and cost spiral.
Then there's the undercarriage - that could be wiped off by a really rough landing ! Lets strengthen that ! Dohhh ! ..............
I think that by that stage in the "redesign" we've grounded the aeroplane ! It won't fly properly or safely now and it's too heavy for it's twelve (I guess) engines to push it into the air.
BTW, bluskis, falling (eventually) into the trap of arguing my engine revs analogy, you do know that commercial jet engines can be damaged by incorrect pilot handling, don't you ?
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stillalbatross,
There have been nearly as many rudder incidents with the A-300 series aircraft as with the 737. Remember, the 737 is the most produced aircraft in commercial history. One takesoff every six seconds. There are 800 in the air at any given time throughout the day. If the rudder issue was a big one, we'd have seen many more accidents/occurences. Many of the purported rudder incidents were identified as yaw damper issues.
Of the two accidents you refer to, one was the Colorado Springs UA (-200) accident which is still indeterminent. The front range of the Rockies is known for violent rotors (horizontal tornados) and as of yet, they have no conclusive evidence the rudder had anything to do with the accident.
The more well known second accident was the USAir near Pittsburgh. While it appears the rudder PCU was made to malfunction by freezing it and then applying a blow torch to it, how this may have occured inflight is still pure conjecture. What is known is that the aircraft rolled and the copilot applied full rudder and full back stick right through the stick shaker. The controls remained that way until impact.
Boeing had to do their research like anyone else. It takes time.
If you want to point fingers at corporate mishandling or directly trying to influence the outcome of an investigation, you need look no further than the AirBus handling of the Habsheim crash. There's all the untidyness revolving around the incomplete control of access to the undamaged CVR and CDR boxes. The delivery took seven hours more than it should have and when the tapes were reportedly examined they had been spliced. The CVR and VDR to this day do not match up. Grab a copy of the Syndicat National des Pilotes de Lignes dated August 1990. It will blow you away. I got mine from a UAL representative who after trying to visit the factory in France to do an article on the new A-320 that UA was about to buy, was called in his hotel room by the head of Airbus and told, "to leave the country immeduately" --which he did.
Not to mention the legion of stories like one I witnessed myself here in the States where an A-320 (Northwest I believe at DTW in 1988) went around and the tower asked, "Where you going?" The crew responded, "We don't know." The aircraft entered holding at the MAP holding fix only to be recovered by a phone patch to France and the sequential pulling of 70 odd circuit breakers. Thank God for extra gas on that one.
How about the footage of the AirBus over France experiencing vast pitch oscillations --with passengers onboard, reportedly due to a software glitch.
I think Boeing's track record in being forthright during accident/incident investigations has been shown to be totally open and honest. The facts in AirBus' behalf clearly speak otherwise.
PT
There have been nearly as many rudder incidents with the A-300 series aircraft as with the 737. Remember, the 737 is the most produced aircraft in commercial history. One takesoff every six seconds. There are 800 in the air at any given time throughout the day. If the rudder issue was a big one, we'd have seen many more accidents/occurences. Many of the purported rudder incidents were identified as yaw damper issues.
Of the two accidents you refer to, one was the Colorado Springs UA (-200) accident which is still indeterminent. The front range of the Rockies is known for violent rotors (horizontal tornados) and as of yet, they have no conclusive evidence the rudder had anything to do with the accident.
The more well known second accident was the USAir near Pittsburgh. While it appears the rudder PCU was made to malfunction by freezing it and then applying a blow torch to it, how this may have occured inflight is still pure conjecture. What is known is that the aircraft rolled and the copilot applied full rudder and full back stick right through the stick shaker. The controls remained that way until impact.
Boeing had to do their research like anyone else. It takes time.
If you want to point fingers at corporate mishandling or directly trying to influence the outcome of an investigation, you need look no further than the AirBus handling of the Habsheim crash. There's all the untidyness revolving around the incomplete control of access to the undamaged CVR and CDR boxes. The delivery took seven hours more than it should have and when the tapes were reportedly examined they had been spliced. The CVR and VDR to this day do not match up. Grab a copy of the Syndicat National des Pilotes de Lignes dated August 1990. It will blow you away. I got mine from a UAL representative who after trying to visit the factory in France to do an article on the new A-320 that UA was about to buy, was called in his hotel room by the head of Airbus and told, "to leave the country immeduately" --which he did.
Not to mention the legion of stories like one I witnessed myself here in the States where an A-320 (Northwest I believe at DTW in 1988) went around and the tower asked, "Where you going?" The crew responded, "We don't know." The aircraft entered holding at the MAP holding fix only to be recovered by a phone patch to France and the sequential pulling of 70 odd circuit breakers. Thank God for extra gas on that one.
How about the footage of the AirBus over France experiencing vast pitch oscillations --with passengers onboard, reportedly due to a software glitch.
I think Boeing's track record in being forthright during accident/incident investigations has been shown to be totally open and honest. The facts in AirBus' behalf clearly speak otherwise.
PT
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IO,
"You twist and misrepresent the facts to suit your opinions."
And you sir evidently operate solely on emotion. You cast aspersions without any factual or creditable evidence nor any pretense thereto.
If you'd like to discuss any of the "facts" I presented that you think are incorrect, I'd be glad to.
Nuff Said.
PT
"You twist and misrepresent the facts to suit your opinions."
And you sir evidently operate solely on emotion. You cast aspersions without any factual or creditable evidence nor any pretense thereto.
If you'd like to discuss any of the "facts" I presented that you think are incorrect, I'd be glad to.
Nuff Said.
PT
Last edited by PlaneTruth; 30th May 2003 at 05:27.
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The problem with the A300605R is the rudder load limiter.
If you do the controll check on the ground you will take about 80 pounds and 4 inches of travel on each pedal to get full travel on the rudder.
2 minutes after takeoff something happens and you put what you think is a measured and restrained 1.25 inch or so input with 22 pounds of force on the rudder pedals and what you think was an extremely restrained mild input turns out to put the rudder on its stops QUICKLY! It is pretty normal to put a 25 percent control input in on a flight control on a transport catagory jet. I do that every day with the elevator during the flare and often enough with the ailerons... What you thought was a similar restrained input in the rudder (something you don't often use) will scare and startle you leading to rapid overcontroll.
Its a trap for POI and is why the A300 600 leads the entire industry in loss of controls in the yaw access. Pretty impressive for such a small fleet of a couple of hundred aircraft.
Cheers
Wino
If you do the controll check on the ground you will take about 80 pounds and 4 inches of travel on each pedal to get full travel on the rudder.
2 minutes after takeoff something happens and you put what you think is a measured and restrained 1.25 inch or so input with 22 pounds of force on the rudder pedals and what you think was an extremely restrained mild input turns out to put the rudder on its stops QUICKLY! It is pretty normal to put a 25 percent control input in on a flight control on a transport catagory jet. I do that every day with the elevator during the flare and often enough with the ailerons... What you thought was a similar restrained input in the rudder (something you don't often use) will scare and startle you leading to rapid overcontroll.
Its a trap for POI and is why the A300 600 leads the entire industry in loss of controls in the yaw access. Pretty impressive for such a small fleet of a couple of hundred aircraft.
Cheers
Wino
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Ah, the old, we can't make it stop what it's doing stories. Legion in the minds of many people and all too unbelievable to be true. In the U.K. when the 737-300 EFIS turned up at Aer Lingus it was alleged that a go around commenced and the crew supposedly said they didn't know what it was doing. Cobblers!! These stories are great bar talk, but little else. As for having to reset 70 circuit breakers to get out of a hold, well that story has been around as long as the A320. It also supposedly happened to an A340, which also apparently, shuts its own engines down in flight, jettisons fuel when it feels like it, etc., etc.
Such garbage, it defies belief; and the more one hears it the funnier it gets, because, presumably, some people actually believe these things happen.
Above all, any pilot who is not capable of disconnecting an autopilot and flying an aircraft to where he wants it to go, if such alleged incidents as the hold one ever took place, should perhaps be in another job. Or I suppose conveniently, the autopilot was sulking as well and refused to disconnect.
Oh boy, I can't wait for the next story, you never know it might, just might one day be based around fact rather than fiction.
Such garbage, it defies belief; and the more one hears it the funnier it gets, because, presumably, some people actually believe these things happen.
Above all, any pilot who is not capable of disconnecting an autopilot and flying an aircraft to where he wants it to go, if such alleged incidents as the hold one ever took place, should perhaps be in another job. Or I suppose conveniently, the autopilot was sulking as well and refused to disconnect.
Oh boy, I can't wait for the next story, you never know it might, just might one day be based around fact rather than fiction.
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There was a program on british tv about Flight 587 and it mentioned the previous incidents of airbus fin loads going over the ultimate load. The transcript of the program is here:
http://www.bbc.co.uk/science/horizon...587trans.shtml
Basically the AA pilots said they no idea that rudder reversals were possibly damaging, and in fact their training told them to use rudder when caught in wake vortices (which might turn a/c upside down).
Airbus said their recommendations are that ailerons are totally sufficient to correct any aircraft upset in a wake vortex (max bank angle 40 deg).
Also, the AA pilots said that they had no idea that the airbus has rudder travel limiters.
From my own experience in maintenance i know that our training went to great pains to explain the travel limiters and how it all works, i find it hard to imaging no-one would tell the pilots.
Then again, i know pilots tend not to get told (or want to know) all lot of things.
Can any A300 pilots out there let us know, were you told?
http://www.bbc.co.uk/science/horizon...587trans.shtml
Basically the AA pilots said they no idea that rudder reversals were possibly damaging, and in fact their training told them to use rudder when caught in wake vortices (which might turn a/c upside down).
Airbus said their recommendations are that ailerons are totally sufficient to correct any aircraft upset in a wake vortex (max bank angle 40 deg).
Also, the AA pilots said that they had no idea that the airbus has rudder travel limiters.
From my own experience in maintenance i know that our training went to great pains to explain the travel limiters and how it all works, i find it hard to imaging no-one would tell the pilots.
Then again, i know pilots tend not to get told (or want to know) all lot of things.
Can any A300 pilots out there let us know, were you told?
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AhhhVC813,
I guess those guys in front of me just went around to log more time on the pay clock. That makes more sense.
Question for an AirBus operator (Wino?): Is it true that the Captain and The F/O each get a vote into the flight control system (along with several other computers) and if the computers decide your input is outside the laws of their programming perameters, they reject your vote?
I was under the opinion as expressed to me by AWest AirBus operators that the "autopilot" was essentially always on. The pilot merely opted for a direct input mode, which was still subject to override by the flight control computer and its programming. Is this correct?
Thanks for the first-hand information Wino.
PT
I guess those guys in front of me just went around to log more time on the pay clock. That makes more sense.
Question for an AirBus operator (Wino?): Is it true that the Captain and The F/O each get a vote into the flight control system (along with several other computers) and if the computers decide your input is outside the laws of their programming perameters, they reject your vote?
I was under the opinion as expressed to me by AWest AirBus operators that the "autopilot" was essentially always on. The pilot merely opted for a direct input mode, which was still subject to override by the flight control computer and its programming. Is this correct?
Thanks for the first-hand information Wino.
PT
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The A300-600 is not fly by wire, although the spoilers are computer controlled. The A320 is fly by wire, but the autopilot is the same as any other aircrafts. Take it out and within the parameters of the control laws you put the aircraft wherever you want it. The control system with the A/P out is the same as any other type, albeit the stabilizer trim is automatic and there is no feel feedback apart from the progressive spring in the sidestick.
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AhhhVC813,
Thanks for the information. Still though, as per your explanation, the pilot input is still subject to approval by the Flight Control Computers and their determination of what is "in the envelope."
The reason I ask is due to puzzling accidents like the East African poorly executed go-around a few years back where the Captain flew into the ground. Evidently the GPWS doesn't override the Flight Control Computers when gear down and close to the ground. (Otherwise, how could you land?)
Thanks for your input.
PT
Thanks for the information. Still though, as per your explanation, the pilot input is still subject to approval by the Flight Control Computers and their determination of what is "in the envelope."
The reason I ask is due to puzzling accidents like the East African poorly executed go-around a few years back where the Captain flew into the ground. Evidently the GPWS doesn't override the Flight Control Computers when gear down and close to the ground. (Otherwise, how could you land?)
Thanks for your input.
PT
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The B737 has an autopilot mode called CWS, when you operate the autopilot through the yoke. The A320 flight control system is operated through the sidestick, but basically it is the same as 737 CWS. You cannot turn the autopilot off - the sidestick is connected to computers, not control surfaces and there is no manual reversion. During conversion, everyone practises landing the aircraft using thrust levers for pitch and rudder trim for yaw. It works nicely in the simulator. Anyone who has "flown" the A320 outside the design envelope will know that the aircraft will then respond in a random fashion to control inputs. Landing in gusty conditions it is not unusual to run out of elevator authority. In really bad conditions aileron authority will also go. The A320 is a good first attempt at fbw, nothing more.
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pom,
Thank you, my point precisely. Once the aircraft Flight Control Computer decides to do it's thing, the pilots input is ignored. The pilot never flies the aircraft, but simply suggests to the computer what direction to go.
There were far too many stories early in the A-320 introduction describing the computers flying a profile far different than that suggested by the pilot. I am told that the cockpit video of the Habsheim crash clearly shows the throttles rammed full forward many seconds prior to impact. Why else would the engines not respond? Unless the pilot simply wanted to fly into the trees, there is only one other explanation: Computer malfunction.
The video of the A-320 pitching wildly over France horrified me, It has been shown here in the States several times and is chilling. Reportedly, it was a revenue flight with people on board.
Anyone out there have first hand knowledge about these incidents? Or others? Or are you willing to speak out?
I'll be the first to admit that Boeing has made it's share of mistakes in the past, but being less than forthright when questions arise about safety is not one of them. The hull loss records for the Classic 737 fleet are half that of the rest of the industry. Half! The 737 has hauled a number of people equal to the Earth's population -over two billion passengers. Given the sparse few accidents in it's past, I think anyone would have to agree it is a proven and safe design. Can it be improved upon? Surely and in many areas, the NG aircraft are light years ahead of the Classic airframes. I have flown Boeing 737 (200,300,500,700) equipment for over 17,000 hours and I have a list of features and design elements that I think could be improved upon. But, the basic airframe is marvelously well engineered. I have had the opportunity to fly at extreme ends of the envelope and have found no vices. We had instances of runaway throttles in the early days of the -700 (they are fbw. Big fun when your engine tries to go to takeoff power as you park at the gate!). A software problem was found and resolved --and that was 1997 software! Similarly, I am sure most of the early software for the fbw in the AirBus had some glitches. How can it not have had a few?
I am not berating the engineers at AirBus, the have made a remarkable fleet of aircraft in a short amount of time. I just think AirBus has been less than honest when issues about their equipment arise. The AA 300 crash is just the latest example. If history is any indication, there will be more.
PT
Thank you, my point precisely. Once the aircraft Flight Control Computer decides to do it's thing, the pilots input is ignored. The pilot never flies the aircraft, but simply suggests to the computer what direction to go.
There were far too many stories early in the A-320 introduction describing the computers flying a profile far different than that suggested by the pilot. I am told that the cockpit video of the Habsheim crash clearly shows the throttles rammed full forward many seconds prior to impact. Why else would the engines not respond? Unless the pilot simply wanted to fly into the trees, there is only one other explanation: Computer malfunction.
The video of the A-320 pitching wildly over France horrified me, It has been shown here in the States several times and is chilling. Reportedly, it was a revenue flight with people on board.
Anyone out there have first hand knowledge about these incidents? Or others? Or are you willing to speak out?
I'll be the first to admit that Boeing has made it's share of mistakes in the past, but being less than forthright when questions arise about safety is not one of them. The hull loss records for the Classic 737 fleet are half that of the rest of the industry. Half! The 737 has hauled a number of people equal to the Earth's population -over two billion passengers. Given the sparse few accidents in it's past, I think anyone would have to agree it is a proven and safe design. Can it be improved upon? Surely and in many areas, the NG aircraft are light years ahead of the Classic airframes. I have flown Boeing 737 (200,300,500,700) equipment for over 17,000 hours and I have a list of features and design elements that I think could be improved upon. But, the basic airframe is marvelously well engineered. I have had the opportunity to fly at extreme ends of the envelope and have found no vices. We had instances of runaway throttles in the early days of the -700 (they are fbw. Big fun when your engine tries to go to takeoff power as you park at the gate!). A software problem was found and resolved --and that was 1997 software! Similarly, I am sure most of the early software for the fbw in the AirBus had some glitches. How can it not have had a few?
I am not berating the engineers at AirBus, the have made a remarkable fleet of aircraft in a short amount of time. I just think AirBus has been less than honest when issues about their equipment arise. The AA 300 crash is just the latest example. If history is any indication, there will be more.
PT
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The 737 has hauled a number of people equal to the Earth's population -over two billion passengers
i still prefer flying airbus, if just as passengers. if i have a look at the american hire-and-fire philosophy, i prefer the aircrafts i'm flying in to be built by skilled people, and not by those rapidly available on the labor market...
or how many airbus do YOU know of just exploded midair?
by,
al
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Has anyone looked at the animated reconstruction on the USA Today of the (commanded, I assume) rudder movements during the upset over the Atlantic in 1997? Just ignoring the fact that the incident began with a stall, the rudder movements seem pretty incidental to recovering the situation - indeed exacerbate it, and this was clearly the case over Rockaway as well. Where is the airmanship and professionalism in flailing away in such a random (and violent) manner on the rudder pedals? It's all very well to blame the French authorities, their US counterparts, composite materials used in primary flight surfaces et al, but the A300 and all other airliners are built to withstand (I believe) 150% of their max design load. In both the AA incidents this was exceeded fairly dramatically.
Three words come to mind reviewing these maneouvres and especially the control inputs in both incidents. Pilot Induced Oscillation.
Three words come to mind reviewing these maneouvres and especially the control inputs in both incidents. Pilot Induced Oscillation.
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AA 903 Pilot creates his own wind shear.!
The application of radical rudder inputs, besides bringing the wing up, also induces yaw transitions which create wind shear forces across the openings of the pitot-static sensors. The resultant low pressures cause erroneous flight instrument indications.
The pilot instinctively reacts to what he believes to be rapid altitude and rate of climb increases and a decrease in airspeed, by shoving the nose down, into a diving attitude, (Projecting the baby out of its mothers arms and the mother up against the ceiling of the aircraft, knocking her unconscious and breaking four of her ribs.!
The instantaneous acceleration, in the dive, at the rate of G, can exceed the aircraft's velocity for a safe recovery.! e.g. NWA 705, EgyptAir 990, United 585, USAir 427, UA 826, ATR 42 in Morroco, SilkAir MI 185, China Airlines 611, COPA Airlines over Tucuti, Panama, etc.!
Excerpt from NTSB letter dated January 21, 1998, "In many cases, as you correctly surmised, pilot reaction to turbulence, mostly inadvertent, does cause more problems than the jolt of turbulence itself."
Wsherif1
The application of radical rudder inputs, besides bringing the wing up, also induces yaw transitions which create wind shear forces across the openings of the pitot-static sensors. The resultant low pressures cause erroneous flight instrument indications.
The pilot instinctively reacts to what he believes to be rapid altitude and rate of climb increases and a decrease in airspeed, by shoving the nose down, into a diving attitude, (Projecting the baby out of its mothers arms and the mother up against the ceiling of the aircraft, knocking her unconscious and breaking four of her ribs.!
The instantaneous acceleration, in the dive, at the rate of G, can exceed the aircraft's velocity for a safe recovery.! e.g. NWA 705, EgyptAir 990, United 585, USAir 427, UA 826, ATR 42 in Morroco, SilkAir MI 185, China Airlines 611, COPA Airlines over Tucuti, Panama, etc.!
Excerpt from NTSB letter dated January 21, 1998, "In many cases, as you correctly surmised, pilot reaction to turbulence, mostly inadvertent, does cause more problems than the jolt of turbulence itself."
Wsherif1
Last edited by wsherif1; 1st Jun 2003 at 15:49.
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theblipdriver,
If you are referring to TWA 800, the jury is still out on that one. While the "O-Ficial" final report identifies hot tank fumes ignited by a wiring spark, I must tell you this:
I had an FAA checkride one day about two years after the explosion. The FAA examiner told me flat out he believed it was a missile. One of his life long friends and associates was a TWA MX technician assigned to the investigation and this gentleman had stated, without a doubt, it was a missile. Others in his area agreed but were censored. He said that in the middle of the metal bending outward (tank explosion mode) there was a clear pireced entry point where the metal was bent inwards, presumably by some object which struck the bottom of the aircraft. Now, that's pretty interesting. (Granted this guy is not an explosives/crash expert.) Furthermore, there are hundreds of witnesses from Long Island who reported seeing a streak of light seconds before the explosion. Perplexing indeed.
I am not a big fan of conspiracies but this one does leave a few untidy questions lingering. Do I think the tank could have exploded per the investigative report? It is a most plausible hypothesis. Still though, the fact that a trained mechanic who examined the wreckage believes otherwise is telling. Where the missile came from is unknown but a shouler launched missile could have been fired from a small boat not far off shore. I'm on the fence on this one myself.
Re:"the american hire-and-fire philosophy" Interesting point. As for the 2 Billion issue, I'll grant you that one. The number I quoted was a few years old and only dealt with the 300/400/500 family.
Latest population update: 07/01/03 6,302,309,691 -all potential customers.
cedarjet747
I asked myself the same question: Why would you get on the rudders during a wake encounter. In my younger days I flew the "Four Fan Trash Can" (C-130H -"Props are for Boats") We used to regularly do minimal interval takeoffs (15 second separation between brake release). You'd have the aileron rolled to the stop and still get spit out of the tip vortices the other direction. NEVER did the aircraft yaw appreciably to cause "rudder flailing" or anything close to it. I have had chance to sample a 767, 747 and other wakes in my 737 and none of them required rudder application. Of course, I was above stall speed in each encounter.
In the '97 event, I think they were trying to aid the apparent aileron effectiveness with some help from the rudder. Problem is, deep into the stall all you do for the low wing when you stomp on the rudder is to accelerate the lower (stalled) wing and get it flying --at the cost of stalling the other wing. If you read the timeline, you can see that was the apparent outcome. The stop-to-stop flailing was clearly an act of deperation by a pilot far behind the power curve. (When we did stalls in the 737, we were warned : NO RUDDER after the break! The slightest yaw at the point of stall can launch you into a spin. A friend from 130's told me about a typhoon chaser C-130 from Guam which survived a 2 turn spin only to land with no wingtips: The outer fuel tanks had taken leave of their outer walls and the wingtips had departed the aircraft. ("It was like that when I got it. Really'")
My only quetion is, "Where the heck was the zoot telegraphed by "radar power" on the throttles? Took awhile to get the turbines wound up it seems. Very odd indeed.
Thanks for the good discussion gentlemen.
PT
edit for population update
If you are referring to TWA 800, the jury is still out on that one. While the "O-Ficial" final report identifies hot tank fumes ignited by a wiring spark, I must tell you this:
I had an FAA checkride one day about two years after the explosion. The FAA examiner told me flat out he believed it was a missile. One of his life long friends and associates was a TWA MX technician assigned to the investigation and this gentleman had stated, without a doubt, it was a missile. Others in his area agreed but were censored. He said that in the middle of the metal bending outward (tank explosion mode) there was a clear pireced entry point where the metal was bent inwards, presumably by some object which struck the bottom of the aircraft. Now, that's pretty interesting. (Granted this guy is not an explosives/crash expert.) Furthermore, there are hundreds of witnesses from Long Island who reported seeing a streak of light seconds before the explosion. Perplexing indeed.
I am not a big fan of conspiracies but this one does leave a few untidy questions lingering. Do I think the tank could have exploded per the investigative report? It is a most plausible hypothesis. Still though, the fact that a trained mechanic who examined the wreckage believes otherwise is telling. Where the missile came from is unknown but a shouler launched missile could have been fired from a small boat not far off shore. I'm on the fence on this one myself.
Re:"the american hire-and-fire philosophy" Interesting point. As for the 2 Billion issue, I'll grant you that one. The number I quoted was a few years old and only dealt with the 300/400/500 family.
Latest population update: 07/01/03 6,302,309,691 -all potential customers.cedarjet747
I asked myself the same question: Why would you get on the rudders during a wake encounter. In my younger days I flew the "Four Fan Trash Can" (C-130H -"Props are for Boats") We used to regularly do minimal interval takeoffs (15 second separation between brake release). You'd have the aileron rolled to the stop and still get spit out of the tip vortices the other direction. NEVER did the aircraft yaw appreciably to cause "rudder flailing" or anything close to it. I have had chance to sample a 767, 747 and other wakes in my 737 and none of them required rudder application. Of course, I was above stall speed in each encounter.
In the '97 event, I think they were trying to aid the apparent aileron effectiveness with some help from the rudder. Problem is, deep into the stall all you do for the low wing when you stomp on the rudder is to accelerate the lower (stalled) wing and get it flying --at the cost of stalling the other wing. If you read the timeline, you can see that was the apparent outcome. The stop-to-stop flailing was clearly an act of deperation by a pilot far behind the power curve. (When we did stalls in the 737, we were warned : NO RUDDER after the break! The slightest yaw at the point of stall can launch you into a spin. A friend from 130's told me about a typhoon chaser C-130 from Guam which survived a 2 turn spin only to land with no wingtips: The outer fuel tanks had taken leave of their outer walls and the wingtips had departed the aircraft. ("It was like that when I got it. Really'")
My only quetion is, "Where the heck was the zoot telegraphed by "radar power" on the throttles? Took awhile to get the turbines wound up it seems. Very odd indeed.
Thanks for the good discussion gentlemen.
PT
edit for population update
Thread Starter
Is there still some confusion out there about which Airbus types have fly-by-wire? Only the A-320/319 through the 330/340 types have the sidestick and strictly computerized inputs to all primary control surfaces (except some trim back-up?), although I've never trained on any Airbus (only jumpseated on the 300 and 320) 
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@PT / TWA800
Hello,
I also heard of the theory of a missile. There were several aircraft which did some "strange things" in this region. TWA800, SWR111, Egyptair, etc. The only reason I don't believe the missile theory is the simple fact that the metal should be bent inward, if the explosion occured outside of the aircraft. Only few missiles have "hit-to-kill"-capabilities, such as the Patriot PAC3. Most missiles have proximity fuses, which will cause hundreds of holes in the fuselage. as for shoulder-launched missiles - they are infrared, so they will aim at the engines, and they have a max. altitude of max. 2-3 miles. the "streak of light" could have been fumes exploding a fraction of a second before the whole aircraft exploded.
In my point of view, a missile hit would simply be too obvious and therefor too difficoult to hide. would it be so difficoult to take some pictures of the metal bent inward and send it to the press? on the other hand - the USN did this before, like the iranian airbus some years ago
but time will hopefully tell...
cheers,
al
I also heard of the theory of a missile. There were several aircraft which did some "strange things" in this region. TWA800, SWR111, Egyptair, etc. The only reason I don't believe the missile theory is the simple fact that the metal should be bent inward, if the explosion occured outside of the aircraft. Only few missiles have "hit-to-kill"-capabilities, such as the Patriot PAC3. Most missiles have proximity fuses, which will cause hundreds of holes in the fuselage. as for shoulder-launched missiles - they are infrared, so they will aim at the engines, and they have a max. altitude of max. 2-3 miles. the "streak of light" could have been fumes exploding a fraction of a second before the whole aircraft exploded.
In my point of view, a missile hit would simply be too obvious and therefor too difficoult to hide. would it be so difficoult to take some pictures of the metal bent inward and send it to the press? on the other hand - the USN did this before, like the iranian airbus some years ago
but time will hopefully tell...
cheers,
al