Solofast, that was a nice piece of Airbus bashing you wrote. You sure went for the jugular! This is of course absolutely not true. No one knows yet what happened on AF 447. Most specialists credit in large part the A-380 flight control system for safely bring the plane back to the ground. Me, I will wait for ATSB's report. Rate of fatal plane crashes per million flights: BOEING MD80/90: 0.24 BOEING 737 300/400/500: 0.16 BOEING 737 600/700/800/900: 0.14 AIRBUS A320/319/321: 0.12 BOEING MD11: 0.50 BOEING 767: 0.36 BOEING 777: 0.0 AIRBUS A340: 0.0 AIRBUS A330: 0.27
The crash AA587 in New York were 265 people died was attributed to the pilots aggressive use of the rudder to control the aircraft even though these inputs took place below manuvering speed. I'm not the only one who thinks this is a design flaw, as can be seen in the quoted from the Wikipedia desccription of the event: I am not the only person who believes that the A300/310 aircraft have a defective tail design. You're supposed to be able to apply any control inputs at a speed below manuevering speed and the aircraft shouldn't come apart. Just because Airbus puts a restriction in the flight manual to prevent you from taking the tail off the airplane doesn't make the substandard design safe. As to AF477, AIRBUS has speculated that the primary cause was a loss of airspeed sensors that resulted in loss of control of the aircraft. For whatever reason, the loss of sensors should not have caused the airplane to crash. This is a prime example of exactly what I am talking about. A perfectly good airplane went out of control (and we still don't know if the tail fell off before or after it hit the water, but I wouldn't bet any money on the tail being on the airplane when it went out of control since the tail was about the only thing found in one piece) because it lost some air speed sensors and the computer couldn't figure out what to do? While this aircraft made it down safely, there are some disturbing aspects here. The outboard engine was not able to be controlled by the pilots following the loss of the inboard engine. Could the outboard engine have just as easily shut itself down? Could that have happened just after rotation when full power is needed? Could the engine have failed to a fixed throttle setting on takeoff that would have made the aircraft uncontrollable on landing? The aircraft landed at high speed with no slats, was there a possibility of an asymmetrical slat extension that would have made the aircraft uncontrollable? The question is, if one other bad thing had happened would we be talking about this as a tragedy and not a near miss. The statistics show that the odds of being in any airliner crash are extremely low. That is not particularly comforting to anybody who has the misfortune to be in an airliner when one happens. More importantly most crashes are a direct result of pilot error and/or landings in bad weather. If you look on the aircraft crash database failure of the aircraft or engines is very seldom the cause of the crash. The problem I have with Airbus aircraft is that the number of crashes that occur with these aircraft due to design and flight control issues is higher than is typical of other transport aircraft and that is why I don't fly them. What you are saying that it's ok to play Russian roulette so long as the odds are good enough, what I am saying "why do you even want to play the game"? I would add, that the FAA looks at it in the same way you are, and that is why my airworthiness requirements are higher than theirs. We had to show the probability of each system failure and that was factored into probability that a specific failure sequence would show up. That is fine if failure rate for each component matches your assumption and is random. But what happens in the real world (and what appears to have happened on AF477) is that the failure rate of one of the systems was much higher than what was originally assumed. When they started having these failures they didn't go back and determine what the probability was for a total failure of the system when the frequently failing part was assumed to be failed. The just kept flying and replacing parts, not realizing that they were an iced up pitot tube away from a total loss of all airspeed input and loss of control of the airplane. Unfortunately for the people on AF477, (if Airbus is to be believed) they simply had a combination of a bad sensor and the other sensors got iced up in a storm, and Ooops... the airplane came down.. Sorry, but that's not an acceptable explanation. And OBTW, the Boeing 767 crash statistics are skewed by 3 hijacked aircraft crashes and one probable suicide by the pilot on the Air Egypt crash off Nantuckett, so it is a lot safer than your numbers would indicate. The MD80/90 series airplanes aren't Boeing's and I avoid them too. The MD-11's are mostly freighters flown by FedEx, so I'm probably not going to be on one. If you ignore the hijackings, the Boeing airplanes are safer than their Airbus rivals by almost a factor of two, and there has been an Airbus 340 crash, that was in 2005, so your data must be older than that.
Solofast, You may not be the only one who thinks this is a design flaw, but with all due respect it's APA job to defend pilots and NTSB never mentioned the tail as "a known structural defect". It is the opposite in fact: http://www.ntsb.gov/publictn/2004/AAR0404.pdf About AF447, I doubt that an aircraft manufacturer would ever "speculate" about an accident before the end of the official inquiry, but you may be right: I do not read Airbus press releases. BAE however clearly demonstrated that all the evidence they have proves that the tail felt off when the plane hit the water. About the A380: I have only read that they were not able to shut it down. I have not yet read anything about it being uncontrollable in flight. If such was the case (which I doubt) then even more kudos to Airbus FCS! No A340 had a "fatal" crash in 2005, so yes, my stats are up to date. (Keyword is fatal) PS: Full disclosure. I crossed the Atlantic 16 times so far this year, 15 times on-board a Boeing 777 and 1 on-board an A330. I like both airplanes and the price is similar to the penny, but the 777 schedule in the day fits me better.
To my knowledge, the 767 has been involved in only one fatal crash where the aircraft was at fault, and that was the Lauda Air crash in Thailand where an uncommanded thrust reverser caused a yaw condition at high speed that led to structural failure. All the other 767 hull losses appear to be the result of hijackings or (probably) suicide. Regarding the still-unsolved Airbus crash over the Atlantic, there have been, to my knowledge, two Boeing 757 crashes where sensor problems led to disaster; one off of the Dominican Republic and one off of Peru. I believe that in both cases, problems with the pitot/static tubes (which in one case had been taped over by mechanics and never untaped) led to pilot disorientation and the aircraft either losing control or flying into the ocean at night. If anyone has more info on these two incidents, please add it.
While the tail failed at twice the structural design load, the tail quite obviously failed due to pilot inputs at a speed below manuevering speed. How that ever got certified is way beyond me. Remember that aircraft are basically certified by their manufacturer, the authorities set the criteria and the manufacturer verifies that the aircraft meet the criteria. In this case the aircraft certainly does not meet the requirement that any control input can be conducted below manuevering speed. The Airbus fed the Europeans the line that the tail was acceptable and they certified the aircraft and by the joint certification agreements and without a lot of review the FAA bought it. That doesn't mean it is safe, that just means that at the time they thought it would be safe. At this point they are so far down the road that they can't do anything about it. The agreed upon "fix" was to institute additional traning and flight manual restrictions on control input to avoid the problem in the future. That was a bandaid at best. Yes it is very interesting that Airbus has made statements that they believe that the crash was caused in part by the loss of airspeed data, when that is not know for certain. Automated warnings were recieved from the aircraft indicating that one airspeed sensor had failed and that the remaining two systems were not in agreement. That means that the airplane didn't know how fast it was going. The twelve warning messages with the same time code indicate that the autopilot and auto-thrust system had disengaged, that the TCAS was in fault mode, and flight mode went from 'normal law' to 'alternate law'. If the control system failed it is possible that the fly by wire system that normally limits the rudder inputs and protects the rudder from excessive may not have been functioning and that could well have taken the tail off the airplane. Airbus has made changes to the pitot static system to address the problems that they were having at the time with the probe systems. They have thus far attributed it to the pitot system, in my opinion, to deflect concern from the tail issue. They simply cannot stand a problem of the magnitude that the realization that the tail design is not sufficient. Compared to the implications of a redesign of the aft fuselage and tail the cost of some sensors is nothing. If it were found that turbulence took the tail off of the plane it would be an economic disaster for them. They apparently did lose control of the engine, the following was copied from https://msquair.wordpress.com/2010/11/06/qantas-flight-qf32-and-common-cause/ It is common to design engine control systems to "fail fixed" if communication with the aircraft is lost. This prevents the control sysetm from shutting down the engine should communication be lost at a critical time like during takeoff. The problem here is that in additition to engine control, the master fuel cutoff valve could not be operated from the cockpit.
Here is a blurb that somebody sent me that sums up what was happening with the systems during this event. This may have been a closer call than I had thought it was. Pretty scary stuff
The damage list. * Massive fuel leak in left middle fuel tank * Massive fuel leak in left inner tank. * Two foot dia. hole in canoe flap fairing. * Aft gallery in fuel system failed preventing fuel transfer * Fuel jettison system inoperable * Large hole in upper wing structure * Partial failure of leading edge slats * failure of speed brakes * Shrapnel damage to flaps * TOTAL LOSS of all hydraulic fluid in Green System * manual extension of landing gear * Loss of one generator and associated systems * Loss of brake anti-skid system * Unable to shut down number one engine using normal procedures due to systems damage * Fire protection system for number one engine inoperable * ECAM warnings regarding major fuel imbalance due to fuel leaks on left side. Unable to cross feed * Fuel trapped in stab. trim tank-possible out-of-balance condition for landing It is reported that Qantas is wrestling with whether or not to try to replace the entire left wing , or return the airplane back to Airbus. The logistics of this huge airplane being grounded are enormous for an operator and Singapore and other operators must be thinking right now.
Rectifying the cause, LONDON (AP) - Rolls-Royce will temporarily replace entire engines suffering from oil leaks on the world's largest jetliner after one motor suffered a frightening midair disintegration, an aviation regulator told The Associated Press on Monday. The official said the British engine-maker would take off faulty engines and replace them with new ones. It will then fix the leaking part and swap the engine back again. The official, who has been briefed by Rolls-Royce and some of the affected airlines, spoke on condition of anonymity because of the sensitivity of the matter. Rolls-Royce declined to comment. Leaking oil caught fire on Nov. 4 in one of the Qantas A380's four massive Trent 900 engines, heating metal parts and causing the motor's disintegration over Indonesia before the jetliner returned safely to Singapore. Experts say chunks of flying metal damaged vital systems in the wing of the Sydney-bound plane, causing the pilots to lose control of the second engine and half of the brake flaps on the damaged wing in a situation far more serious than originally portrayed by the airline. Qantas grounded its six A380s within hours and said four days later that checks had revealed suspicious oil leaks in three engines on three different grounded A380s. Singapore Airlines and Lufthansa, which both use A380s with Trent 900 engines, have conducted checks on their superjumbos and all but one have returned to service, the airlines say. Qantas' six superjumbos - the backbone of its longest and most lucrative international routes between Australia and Los Angeles, Singapore and London - remain grounded despite what experts say is financial pressure to fly them again. The removal of engines can be expected to cause longer delays and potential revenue losses. "We are taking our normal and extremely conservative approach to safety and will not operate our A380 fleet until we are completely confident that it is safe to do so," Qantas spokesman Simon Rushton said. Airbus said last week that the Trent 900 problems could be expected to delay deliveries of new A380s. Deutsche Lufthansa AG spokesman Thomas Jachnow declining to comment on any engine replacement, saying only that the company's engineers were in close contact with Rolls-Royce. The company has the delivery of a fourth A380 scheduled for tomorrow. The plane underwent all the new tests mandated by the European Air Safety Agency last week, Jachnow said. The next four A380 deliveries are scheduled for the first half of 2011 and Lufthansa expects no delays, he said. Jachnow said the company has ordered a total of 15 A380s, all of them are to equipped with Trent 900 engines. Airbus spokesman Justin Dubon directed questions about the engines to Rolls Royce and said, "We're helping with the investigation in order to minimize disruption to customers." Qantas was still hopeful of returning the A380s to service "in days, not weeks," Rushton said. Britain's Rolls-Royce Group PLC, the world's second-largest engine maker, said Friday that it would be replacing an unspecified module, or collection of linked parts, on the Trent 900. Airbus said Rolls-Royce would also be equipping the engines with software to shut them down before an oil leak could cause an engine to disintegrate. Rushton said three engines had been removed from Qantas A380s as part of a detailed inspection program ordered by Europe's air safety regulator and recommendations by Rolls-Royce. Singapore Airlines, which grounded three of its 11 A380s after checks found oil leaks in three Trent 900s, said Monday that two were back in service after engine changes and that work was continuing on the third. "We can't speak definitively about the number of engines that may ultimately require modification work as it needs to be stressed that investigations are continuing," Singapore Airlines spokesman Nicholas Ionides said. Rolls-Royce shares fell further Monday after a brief respite on Friday when the company revealed it had identified the faulty component and was working with airlines to fix the problem. The stock, trading at 596.5 pence ($9.60) at Monday's close on the London Stock Exchange, has now lost 9 percent, or around $1.4 billion, since the Qantas midair incident on Nov. 4.
Holy crap, that is a serious list of repairs. I'd imagine this specific aircraft to be out of commission for a while; would it not be more efficient to have it replaced? This is serious stuff.
I'm really not sure what the big deal is. Everybody is getting all excited like this is the first English engine to leak a little oil and require premature rebuild.
An engineer for Lockheed posted this on another forum. Only one pice here but you guys in the industry will get to see the whole set as it's mailed around. Image Unavailable, Please Login
This is a blurb from MyWay news... If you read between the lines here carefully, the issue is RR probably KNEW they had a problem before that engine blew up. They didn't think it was bad enough or wouldn't get bad enough before they could update the fleet so they kept it close to the vest and were doing a silent campaign to fix the engines before the Nov 4 incident. This is but another example where a company doesn't want to admit that they have a problem and is willing to take the risk that it won't get bad enough to cause a big failure before they can fix it and keep it quiet. The right thing would have been to tell the FAA they had a problem and require frequent recurrent inspections, but they didn't do that and this is what happened. In my experience RR is very arrogant about things like this (the standing joke is you can't spell arrogant unless you have two nested R's in the middle) and they have a very cozy relationship with the airworthiness authorities in Europe, so this kind of thing can happen there without reprocussions. Wonder if we should put RR engines on the list of things we won't fly on...
I know the 2 companies (RR aviation and RR cars) have been seperate for many years but I still can't help but have the feeling that RR aviation has the same institutionalized arrogance and superiority complex all other British industries have. It caused the demise of their motorcycle industry and led to the auto industry to be near wholly foriegn owned. If you cant bottle and drink it they have trouble making it well.
This appears to be a heavy forging that is imbedded in a lot of wing structure and it looks like there is a hole above it that could be wing skin. This kind of damage on an airplane this big ain't gonna be easy or cheap to fix. Two pieces of primary structure or just one critically located element is going to require jigging the wing and dismantling some heavy close tolerance parts. And this isn't all of it.
I would have thought that a forged part would have shown more ductility on the failure surface. The fracture surface here doesn't show much deformation, just a brittle fracture where the hole was punched out and a little bit of bending on both ends of one of the ribs. Maybe they heat treated the heck out of the part to gain strength and that made it really brittle, but that's really an odd kind of failure for that kind of part. Pretty scary...
The way it broke does look like a casting. Looks like a number of sheared wiring bundles on the other side. Explains loss of so many systems.
