for June, 2011
Another fledgling leaves the nest! Congratulations to Anton Likhtarov who soloed Citabria 1806G under Erik Schmidt’s careful guidance.
Well done Anton and Erik.
Congratulations to our own AeroDynamic CFI Dick Chang, who added a Rotorcraft-Helicopter rating to his pilot license recently.
Dick trained at Bristow Academy in Concord, flying the Schweizer 300, and then aced his checkride with Examiner Ken Suzuki.
Well done Dick!
Congratulations to Jimmy Shih who flew a Citabria solo for the first time after being let loose by his instructor Rimas.
Jimmy is already an acomplished pilot, and he wanted to add taildragging to his skills because his next flying ambition is aerobatics.
From: Ray Fowler
The Liberty Foundation, Chief Pilot
First, let me start off by sincerely thanking everyone for the outpouring of support that we are receiving. I am sorry that I have not yet had the opportunity to return the many phone calls, text or e-mails that I am receiving offering to help. Again, thank you for all of the kind words that we are receiving and for incredible offers to help emotionally, financially and/or with the recovery process. I hope this statement will help fill in a few details that everyone is wondering about that led to the loss of our “Liberty Belle”.Yesterday morning, both our P-40 and B-17 were scheduled to fly from Aurora, Illinois to Indianapolis, Indiana. We were in Aurora for the weekend as a part of our scheduled tour. Over the course of the previous week, we completed a scheduled 25-hour inspection on the B-17 which was completed by Saturday. On Saturday, the weather stayed below the required ceiling to give any passenger flights, however the B-17 flew in the morning on a routine training proficiency flight, performing several patterns. Following the flight, other maintenance issues arose that required us to cancel our Sunday flying schedule for repairs. The maintenance performed has not been, in any way, associated to the chain of events that led to Monday’s fateful flight, but is being considered in the preliminary investigation. However, due to the media’s sensational (mis)reporting, there is a large amount of misinformation that continues to lead the news.
Here is what we do know… Flying in the left seat of the B-17 was Capt. John Hess. John has been flying our Liberty Belle since 2005 and one of our most experienced B-17 pilots. He is an active Delta Air Lines Captain with over 14,000 hours of flying experience and flys a variety of vintage WWII aircraft. In the right seat was Bud Sittig. While Bud is new to the Liberty Foundation this year, he is also incredibly experienced with over 14,000 hours of flying time in vintage and hi-performance aircraft. He is a retired Captain with Delta Air Lines.
The news misidentified the P-40 as flying chase during the accident. I was flying our P-40, however I had departed 20 minutes prior to the B-17’s takeoff on the short flight to Indianapolis to setup for the B-17’s arrival. The aircraft flying chase was a T-6 Texan flown by owner Cullen Underwood. Cullen is one of our rated B-17 Captains and an experienced aviator tagging along as a support ship.
The takeoff of both aircraft was uneventful and proceeded on-course southeast. Prior to exiting Aurora’s airport traffic area, the B-17 crew and passengers began investigating an acrid smell and started a turn back to the airport. Almost immediately thereafter, Cullen spotted flames coming from the left wing and reported over the radio that they were on fire.
As all pilots know, there are few emergency situations that are more critical than having an in-flight fire. While it is extremely rare, it can (and sometimes does) indiscriminately affect aircraft of any age or type. In-flight fires have led to the loss of not only aircraft, but often can result in catastrophic loss of life. It requires an immediate action on the flight crew, as the integrity of aircraft structure, systems and critical components are in question.
Directly below the B-17 was a farmer’s field and the decision was made to land immediately. Approximately 1 minute and 40 seconds from the radio report of the fire, the B-17 was down safely on the field. Within that 1:40 time frame, the crew shutdown and feathered the number 2 engine, activated the engine’s fire suppression system, lowered the landing gear and performed an on-speed landing. Bringing the B-17 to a quick stop, the crew and passengers quickly and safely exited the aircraft. Overhead in the T-6, Cullen professionally coordinated and directed the firefighting equipment which was dispatched by Aurora Tower to the landing location.
Unlike the sensational photos that you have all seen of the completely burned B-17 on the news, you will see from photos taken by our crew that our Liberty Belle was undamaged by the forced landing and at the time of landing, the wing fire damage was relatively small. The crew actually unloaded bags, then had the horrible task of watching the aircraft slowly burn while waiting for the fire trucks to arrive. There were high hopes that the fire would be extinguished quickly and the damage would be repairable. Those hopes were diminished as the fire trucks deemed the field too soft to cross due to the area’s recent rainfall. So while standing by our burning B-17 and watching the fire trucks parked at the field’s edge, they sadly watched the wing fire spread to the aircraft’s fuel cells and of course, you all have seen the end result. There is no doubt that had the fire equipment been able to reach our aircraft, the fire would have been quickly extinguished and our Liberty Belle would have been repaired to continue her worthwhile mission.
Let me go on the record by thanking the flight crew for their professionalism. Their actions were nothing short of heroic and their quick thinking, actions and experience led to a “successful” outcome to this serious in-flight emergency. John and Bud (and Cullen) did a remarkable job under extreme circumstances and performed spectacularly. While the leading news stories have repeatedly reported the “crash” of our B-17, fact is they made a successful forced landing and the aircraft was ultimately consumed by fire. Airplanes are replaceable but people are not and while the aircraft’s loss is tragic, it was a successful result.
This leads me into discussing the exceptional safety record of the Boeing B-17 and to hopefully squash the naysayers who preach we should not be flying these types of aircraft. Since we first flew the “Liberty Belle” in December of 2004, we have flown over 20,000 passengers throughout the country and if you count our historic trip to Europe in 2008, worldwide. Of the other touring B-17s, some of which that have been touring for over 20 years, they have safely flown hundreds of thousands of people. The aircraft’s safety record is spectacular and I am certain the overall cause of our issue, which is under investigation, will not tarnish that safety record. In fact, as many of you know, other B-17 have suffered significant damage (although not as bad as ours!), only to be re-built to fly again. From a passenger carrying standpoint, I can think of few aircraft that offer the same level of safety as the 4-engine “Flying Fortress”. As mentioned earlier, in-flight fires are extremely rare and certainly could affect any powered aircraft under certain circumstances. I would put my children today in any of the other touring B-17s to go fly. I suggest to anyone that was thinking of doing so when a B-17 visits your area to do so without giving our loss any thought.
There is wild speculation going on as to the cause of our fire and the affect to other operators. Please let the investigation run its course and report the findings. The NTSB and FAA were quickly on the scene and we are working closely with them to aid in the investigation. As soon as we receive some additional information, we will release it via the website http://www.libertyfoundation.org/.
The ultimate question remains, where does the Liberty Foundation go from here? After the investigation and recovery, we will determine our options. We are still committed to the restoration and flying of World War II aircraft. Again, we appreciate the support and people offering to help get us back flying.
Please check back for updates. I will close by thanking everyone that made our tour so successful. From the first day of the B-17’s restoration, thank you for all of you who labored to get her flying over the initial restoration years and to everyone that has worked on her out on tour since. Thank you to the crewmembers, tour coordinators and volunteers who gave up weekends and countless hours to support her on the road. And finally, thank you to the passengers, donors and media patrons that flew aboard and everyone who supported our cause. Hopefully, this will not be the end of the story, but a new beginning.
Much has been said about how the pilots of AF reacted incorrectly to an impending stall, but did they really? It would appear that initially maybe they did raise the nose, but it also seems the plane’s autotrim then kept the nose up despite efforts to get it back down. However, there should have been plenty of time and altitude to recover. As has been mentioned elsewhere, the plane was not in a departure from controlled flight, it held the nose up accurately and the wings responded to roll inputs. So why did it stay nose up for what must have been a terrifying three minutes? Why, even after the Captain entered the cockpit and commanded nose down, did the nose stay up?
Here’s an analysis from Der Spiegel that raises disturbing questions about the airplane’s control systems. I thought it was interesting enough to post the whole article rather than just a link, but you can also click on image above to go to Der Spiegel web site:
Questions Raised about Airbus Automated Control System
Der Spiegel (Germany) 05/30/2011
Author: Gerald Traufetter
It took just three-and-a-half minutes for Air France flight AF 447 to plunge 11,000 meters into the Atlantic two years ago. An initial analysis of the plane’s data recorder hints at errors made by the pilots. But questions have also been raised about the A330’s automated control systems.Everything pointed to a routine flight, two years ago. The Airbus A330 was flying along at its cruising altitude high above the Atlantic Ocean and had just passed an area of light turbulence. The captain of the flight, Marc Dubois, left the cockpit for a bit of rest.
Co-pilot Pierre-Cédric Bonin, whose wife was a passenger onboard the aircraft, told the cabin crew that “in two minutes we should enter an area where it’ll move about a bit more than at the moment.” The co-pilot’s exact words are part of the interim report on the crash of Air France flight AF 447, released by the French aviation accident investigation agency BEA on Friday. The report, dry and almost entirely free of commentary, provides insight into the final three-and-a-half minutes of the flight, before it plunged into the Atlantic killing all 228 people on board.
Based on an initial analysis of the flight data recorders, the anticipation prior to the report’s release was high. Both the data recorder and the voice recorder belonging to the Airbus, which crashed on June 1, 2009, were found on the ocean floor at a depth of 4,000 meters (13,125 feet) in early May.
‘A Mysterious Crash’
The crash of the A330 had made millions of airline passengers uneasy. How, many wondered, was it possible for a passenger jet to simply be lost as it traversed the ocean? It was reminiscent of ships disappearing without a trace on the high seas in bygone centuries. Would the data recorders finally solve the mystery?
It was only much later, after hours of radio silence and well after the plane was scheduled to have completed its crossing of the Atlantic, that planes were dispatched to search for the missing Airbus.
Even experienced accident investigators were caught completely off guard by the calamity. “This is a mysterious crash,” said Peter Goelz, former head of the National Transportation Safety Board (NTSB) in Washington. He said it was in the same category as air disasters such as that on the island of Tenerife in 1977, with 583 deaths, the deadliest in the history of air travel.
On Wednesday of this week, families of the victims — from 32 countries — are set to gather in Paris and Rio de Janeiro to mark the second anniversary of the crash. The meeting is taking place at a time when the veil that has covered the accident in mystery may slowly be lifting. The four-page BEA report provides answers to several of the most pressing questions the crash left behind — and raises just as many additional issues.
The drama began at 2:10 a.m. and 5 seconds GMT: Without warning, the autopilot and the auto-thrust disengaged. The report is silent as to why. But crash investigators have an explanation: The three speed gauges on the outside of the aircraft, known as pitot sensors, had become iced up.
Extremely Dicey Situation
Suddenly, the routine flight turned into a nightmare. “I have the controls,” co-pilot Bonin told his colleagues. At that point, the aircraft pitched to the right and Bonin quickly moved to correct and to pull up the plane’s nose. His colleague informed him: “We’ve lost the speeds.”
It must have been clear to both of them that they were suddenly in an extremely dicey situation. At the plane’s cruising altitude of 11,000 meters (36,000 feet), maintaining a precise speed is critical. Just 15 kilometers per hour (9.3 mph) faster or slower and the plane can stall. With the margin of error so small, pilots call this altitude “coffin corner.”
And it wasn’t long before the cockpit was pierced with the feared warning: “Stall! Stall!” The warning comes from a synthetic voice and is accompanied by signal loud enough that the business class passengers behind the cockpit must have been able to hear it.
In such moments, however, the noise from outside the aircraft is one that heralds disaster. The sound of the wind rushing past disappears and only the high-pitched whines of the two turbines is audible inside the cabin. Aviation experts know that the noise means that the plane’s wings are no longer providing enough lift.
It is at this moment in the sequence of events where expert opinions diverge when it comes to the answer to the most fundamental of all questions: Who was to blame for the deaths of the 228 people on board the flight? An animated debate has erupted between the plane’s manufacturer Airbus and other experts. The interim report is short on clear answers.
A Serious Error
The pilots reacted to the stall warnings with maximum thrust — just as was called for in the training manuals. But they also pulled the nose of the aircraft up. It is an intuitive thing to do, but aeronautically it is a serious error.
Increased thrust can result in an aircraft’s nose rising on its own and manufacturers themselves have recognized the problem. In a Flight Operations Telex dated May 12, 2010, Airbus removed the maximum thrust instruction from its flight manuals.
But why would co-pilot Bonin pull up instead of pushing the nose down? It wasn’t long before the plane’s angle to the onrushing air became dangerously high.
An explanation for the A330’s rising nose, however, could also be provided by a line in the BEA report referring to the trimmable horizontal stabilizer. Situated at the tail of the aircraft next to the flaps controlling the aircraft’s pitch, known as the elevator, the horizontal stabilizer likewise helps control the plane’s horizontal stability. According to the BEA’s interim report, the horizontal stabilizer moved from three degrees to 13 degrees, almost the maximum. In doing so, it forced the plane into an increasingly steep climb. It “remained in the latter position until the end of the flight,” the report notes.
Airbus considers the reading not to be out of the ordinary and refers to the co-pilot’s efforts to pull the nose up.
But Gerhard Hüttig, a professor at the Institute of Aeronautics and Astronatics at the Technical University in Berlin, considers the high angle of the horizontal stabilizer to be a failure of the Airbus’ electronic flight control system. Hüttig, a former Airbus pilot himself, calls it “a programming error with fatal consequences.”
“No matter how hard the crew tried to push down the nose of the aircraft, they would have had no chance,” Hüttig says. He is demanding that the entire fleet of Airbus A330s be grounded until the phenomenon is adequately explained.
The BEA report, in its current form, only provides the angle of the stabilizer but provides no explanation as to why. The report merely indicates that it was at this moment that Captain Marc Dubois re-entered the cockpit.
Exactly what orders he issued are not part of last Friday’s report. But sources close to the investigation are saying that he said: “This is a stall. Reduce power and nose down!”
This order would have been the correct one were the situation not already hopeless. By that time, the jet, which was pointing steeply upwards, was already losing vertical altitude at a rate of 200 kilometers per hour.
The passengers, who had just a short time before been pressed into the backs of their seats, were now being held into their seats only by their seatbelts. “At this moment, I would have feared for my life even if I was sitting in the passenger cabin,” said one A330 pilot after reading the BEA report. That the plane was in freefall would have been clear to all on board. The nose of the plane pointed skyward at an angle of 16 degrees. “That’s more than immediately following takeoff,” the pilot said.
In its report, the BEA has only published statements from the pilots that contain information about technical matters. “I don’t have any more indications,” said the co-pilot Bonin, for example. One and a half minutes of free fall later, he said: “We’re going to arrive at level one hundred.” That means that the plane is only 3,000 meters above sea level.
The last few minutes of Flight AF 447 must have been especially tragic for Captain Dubois. The rules do of course stipulate that the captain can rest in the rear area during this phase of the flight. But why did he not remain in the cockpit until they had passed through the storm?
On his return, the experienced pilot recognized the situation immediately and issued the correct commands. But if the suspicion of aviation expert Hüttig is accurate, by this stage it was too late to change anything.
Indeed, the BEA report documents efforts undertaken following the captain’s return to bring the plane’s nose down. Forty-one seconds before impact, both co-pilots were pushing on the controls. Then Bonin cried desperately: “Go ahead, you have the controls.” There were just 30 seconds left before the end.
But why were all the crew’s efforts in the cockpit in vain? Did the plane no longer react to the cockpit commands as it fell? Or did the horizontal stabilizer, which was still almost fully deflected at 13 degrees, continue to force the nose of the plane up?
Airbus vehemently denies that the plane’s automatic controls could have worked against the pilots’ commands. Were the suspicions proven true, however, then the software would have to be replaced in over a thousand A330s and in its sister model, the A340. The costs would run into hundreds of millions of euros.
In any case, flight engineer Hüttig, who also advises the victims’ families regarding technical issues, is concerned about the description of the horizontal stabilizer as being at 13 degrees. That is consistent with behavior he observed in an Air France A330 simulator in Paris a few months ago, when he replicated the situation together with other pilots. “The phenomenon is startlingly similar,” he says.
Was it really the stabilizer that doomed the pilots? In theory, they could still have adjusted it — its position can be manually altered using a wheel near the thrust levers. But as Hüttig notes, one would first have to know that the stabilizer is deflected.
Huttig pointed out that Airbus published a detailed explanation of the correct behavior in the event of a stall in the January issue of its internal safety magazine. “And there, all of a sudden, they mention manually trimming the stabilizers,” he says.
It remains an open question who will be proved right at the end of the investigations. But it is already clear that no one individual will bear the burden of responsibility alone. The pilots could have stabilized the aircraft if they had reacted differently. But the airline had also probably not prepared them properly for such a situation. Similarly, Airbus’ recommendations were insufficient. That much is spelled out in the files of the French authorities which investigated the crash of the A330. “To date,” the experts say, the deficiencies have “not been rectified.”
If the speed sensors fail, it has a “particularly confusing” effect in Airbus models, the experts say, pointing to the high degree of automation in the cockpit. “If the control computers, which are actually supposed to provide more safety, fail, then the automatic systems can become a danger at that moment,” says William Voss, president of the Flight Safety Foundation.
‘No Unsafe Condition’
The manufacturer Thales was well aware of the catastrophic consequences of a failure of the speed sensors as early as 2005. At the time, the French company concluded that such a failure could “cause plane crashes.”
A total of 32 cases are known in which A330 crews got into difficulties because the speed sensors failed. In all the cases, the planes had pitot sensors from Thales, which were significantly more prone to failure than a rival model from an American manufacturer.
But none of the responsible parties intervened. In 2007, Airbus merely “recommended” that the sensors be replaced. Air France took that as a reason not to carry out the costly work — and it even got official blessing for doing so. The European Aviation Safety Agency wrote that it currently saw “no unsafe condition that warrants a mandatory modification of the Thales pitot tubes.”
The letter was sent on March 30, 2009, almost two months to the day before Flight AF 447 ended in tragedy.
In their accident report, the BEA investigators noted the end of the recordings at 2:14 a.m. and 28 seconds on June 1, 2009: “The last recorded values were a vertical speed of -10,912 ft/min.”
In other words, the Air France plane hit the Atlantic at a speed of almost 200 kilometers (124 miles) per hour.
Also see http://www.flightglobal.com/articles/2011/06/01/357394/stalled-af447-did-not-switch-to-abnormal-attitude-law.html for a discussion about autotrim and indeed accidents caused by it.
Andrea is working on her instrument rating and decided that taming a taildragger would make a nice break.
Not only did she tame a taildragger in two thirds of average time, but then she also took on some aerobatics. Well done Andrea and AeroDynamic CFI Mark Guerrero.
Another fledgling flies solo! Congratulations to AeroDynamic member Stephane Dahan who is training with CFI Mark Guerrero.
Stephane flew three great takeoffs and landings in a Citabria on his own while Mark watched from the ground. Well done Stephane and Mark!