CVR

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Germanwings Crash – French Investigation is Far from Conclusive

Posted by George Brown on 29/03/2015

Posted in: Aviation, Crime, Law. Tagged: air safety, Aircraft carrier, aviation, crime, CVR. 1 Comment

Readers of this blog will recall my post Germanwings Crash – Deliberate act by Co-pilot? where it is suggested that the co-pilot deliberatly flew the Airbus A320 into the French Alps.

D-AIPX, the Airbus A320-200 involved in the accident. Image by Sebastien Mortier via Wiki Creative Commons.

I came across this story today by Christine Negroni which takes a somewhat alternate and plausible view of what may have happened on the flight deck of the Germanwings aircraft. I tend to agree with her, as it is far too early to conclusively say what has occurred. I know when the “murder-suicide” theory was brought to my attention by a colleague, I replied that the thought of this being a deliberate action was too “bizarre” to contemplate, and bordered on conspiracy theory. But French investigators were saying that was so, therefore it must be – right?

So I’m now glad that somebody else sees the possibility of another cause of this disaster!

The news coming from the French prosecutor Brice Robin regarding Monday’s crash of Germanwings Flight 9295 is shocking, but on what facts is the statement based? Surely Mr. Robin knows something he’s not sharing with the rest of us, or how could he possibly come to the conclusion that “the co-pilot wanted to destroy the aircraft”? And yet that is what he is saying based on facts that still could suggest other possibilities.

The evidence so far suggests first officer Andreas Lubitz deliberately flew the plane to a lower altitude. What we do know is that the plane wound up crashing into a mountain. The question Mr. Robin has not answered is how he knows the co-pilot had that end in mind.

We know the plane was commanded down to a lower altitude after reaching 38,000 feet. We do not yet know why.

We know the Captain, identified in as Patrick Sonderheimer, left the cockpit and was unable to get back in. We do not know that he tried to enter using the door passcode or that the door was blocked beyond the normal locking function. All we know is that the cockpit voice recorder shows he tried to enter by knocking. There is a suggestion that an axe was used to try and gain access to the flight deck – ed.

There may be reasons for trying to enter by knocking, including confusion or distraction due to alarm.

We know that the first officer Lubitz failed to heed the knocks on the door. We do not know if this was deliberate. We know Lubitz was breathing. Both his inappropriate action in not heeding the knocking on the door and his breathing is consistent with deliberate action OR incapacitation.

We know the plane descended. We do not know if this was via programming the plane to descend or flight by hand by the first officer. A conscious and lucid pilot does not fly a plane into a mountain unless it is deliberate. An addled or unconscious pilot does not see or recognize the threat of a mountain and does. Either one of those options is possible, but the evidence presented so far does not allow conclusions.

Finally, unlike in the United States and other countries, the French judicial authorities are in charge of cockpit voice recorders and flight data recorders, which then makes them available to the air safety agency the Bureau d’Enquêtes et d’Analyses. There’s a reason for this increased oversight: In the crash of an Airbus A-320 in 1988, BEA was suspected of tampering with FDR data.

As a consequence, air accidents in France are seen through the prism of criminality. In other countries seasoned air safety investigators understand there is a multitude of factors that contribute to a disaster and will wait to have all the evidence before drawing conclusions.

This is the only way I can understand how the Marseilles French prosecutor made the tremendous leap of logic in concluding that the first officer “wanted” to crash the plane killing all 150 onboard.

The evidence so far shows Lubitz deliberately flew the plane to a lower altitude and a crash resulted. The question not answered in anything I’ve heard or seen is whether he intended for that to happen. This is not a subtle quibble. It makes a monumental difference in what really happened to Germanwings Flight 9295.

Source: Christine Negroni is an aviation journalist and safety specialist who is writing a book on aviation mysteries to be published by Penguin in 2016. This story first appeared on her blog.

MH370 – FDR/CVR Pulse Detected?

Posted by George Brown on 06/04/2014

Posted in: Aviation, Crime, Emergency Services, Media, News, Opinion, Safety, Software, Technology, Uncategorized. Tagged: 37, 5KHz, 9M-MRO, acoustic signals, Angus Houston, Australian ship, CVR, FDR, Houston, Joint Agency Coordination Centre, Malaysia Airlines, MH370, Ocean Shield, Royal Australian Air Force. 3 Comments

PLANES and ships are being diverted to the area where a Chinese vessel detected signals at 37.5kHz, consistent with a black box transmissions in the hunt for missing flight MH370, while an Australian ship is checking out another “acoustic event”.

“Today Royal Australian Air Force assets will deploy to assist in further examining the acoustic signals in the vicinity of where the Chinese ship has detected the sounds,” said Angus Houston, head of the Joint Agency Coordination Centre leading the search.

“HMS Echo and Australian Defence Vessel Ocean Shield are also being directed to join Haixun 01 as expeditiously as possible to assist with either discounting or confirming the detecting.”

Haixun 01 Source: AMSA

Houston said the Australian vessel Ocean Shield would be delayed while it investigated a separate acoustic signal in its current search location that had only been detected in the last hour. “We do not have any detail on the encounter at this stage,” he said. “We just know that there has been an acoustic detection by Ocean Shield which has highly sophisticated equipment and the word I have got is that it is something that needs to be investigated. “I’m not prepared to speculate on what it might be and what it might not be.” The Haixun 01 signal, which lasted for 90 seconds, was picked up during searches on Saturday. The Chinese ship had already detected a more fleeting signal on Friday, Houston said. He described the development an “important and encouraging lead but one which I urge you to continue to treat carefully”. “We are working in a very big ocean and within a very large search area, and so far since the aircraft went missing we have had very few leads which allow us to narrow the search area,” he said.

Houston said the mission was treating both acoustic signals “very seriously” but he said the Haixun 01 detection was the most promising lead.

HMS Echo Photo: http://www.pstew.co.uk

The retired Australian defence chief also said that corrected satellite data had shifted the focus for the hunt for the missing plane to the southern area of the search, the area that Haixun 01 is operating in.

“The whole of the existing search area remains the most likely area that the aircraft entered the water, but based on the new advice the southern area now has a higher priority,” he said.

Houston urged caution, saying he did not want to put the families of those onboard the missing flight under further stress.

Source: The Australian

A Look at “Black” Boxes

Posted by George Brown on 06/04/2014

Posted in: Aviation, Education, Safety, Software. Tagged: black box, black boxes, CVR, FDR, Malaysia Airlines, MH370. Leave a comment

With Malaysia Airlines Flight 370 is confirmed lost in the southern Indian Ocean, focus is turning to the retrieval of the flight’s “black box”.

The US has sent a black box locator to the search area, with less than two weeks to go until these crucial pieces of equipment stop transmitting.

Here are some things you might not know about black boxes:

1. They’re not black

Black boxes are the same colour as the Golden Gate Bridge in San Francisco … kind of. They are a tone of what’s known as international orange, which is a set of three colours used in aerospace and engineering to distinguish objects from their surroundings. The Golden Gate Bridge is a darker shade, while the international orange used for black boxes is much brighter.

Photo:The tone of international orange used to paint the Golden Gate Bridge is most closely matched by Pantone colour 180. (AFP: Justin Sullivan)

2. A ‘black box’ comes in two parts

The “black box” is made up of two separate pieces of equipment: the flight data recorder (FDR) and a cockpit voice recorder (CVR). They are compulsory on any commercial flight or corporate jet, and are usually kept in the tail of an aircraft, where they are more likely to survive a crash. FDRs record things like airspeed, altitude, vertical acceleration and fuel flow. Early versions used wire string to encode the data; these days they use solid-state memory boards. Solid-state recorders in large aircraft can track more than 700 parameters.

Photo: The black boxes from the Asiana plane that crashed short of the runway at San Francisco airport on July 6, 2013. (Twitter: @NTSB)

3. They were invented by an Australian

Dr David Warren’s own father was killed in a Bass Strait plane crash in 1934, when David was just nine years old. In the early 1950s, Dr Warren had an idea for a unit that could record flight data and cockpit conversations, to help analysts piece together the events that led to an accident. He wrote a memo for the Aeronautical Research Centre in Melbourne called “A Device for Assisting Investigation into Aircraft Accidents”, and in 1956 produced a prototype flight recorder called the “ARL Flight Memory Unit”. His invention did not get much attention until five years later, and the units were eventually manufactured in the UK and US. However, Australia was the first country to make the technology compulsory.

4. Experts don’t call them “black boxes”

The term “black box” is favoured by the media, but most people in the know don’t call them that. There are several theories for the original of the name “black box”, ranging from early designs being perfectly dark inside, to a journalist’s description of a “wonderful black box”, to charring that happens in post-accident fires.

Black boxes are normally referred to by aviation experts as electronic flight data recorders. Their role is to keep detailed track of on-flight information, recording all flight data such as altitude, position and speed as well as all pilot conversations. It is common for many civil airliners to have multiple devices to carry out these tasks so that information can be gathered more easily in the event of a failure. In most instances, they are used to help in the diagnosis of what may have been the likely cause of an accident.

5. Only 2 hours of cockpit conversations are kept

Digital recorders have enough storage for 25 hours of flight data but only two hours of cockpit voice recording, which is recorded over itself in a loop. The CVRs track the crew’s interactions with each other and air traffic control, but also background noise that can give vital clues to investigators. Earlier magnetic tape versions could only record 30 minutes of cockpit conversations and noise, which was also recorded in a loop.

Alaska Airlines 261 flight data recorder

Photo: The magnetic tape flight data recorder from Alaska Airlines Flight 261 was retrieved off the coast of California after the plane crashed in 2000. (AFP: Manny Ceneta)

6. It can take a long time to find one

Towed Pinger Locator for finding black boxes

Photo: A US Navy Towed Pinger Locator (TPL) has been sent to help find MH370’s black box. (Supplied: US Navy)

Black boxes are fitted with an underwater locator beacon that starts emitting a pulse if its sensor touches water. They work to a depth of just over four kilometres, and can “ping” once a second for 30 days before the battery runs out, meaning MH370’s black box is due to stop pinging around April 7, 2014. After Air France flight 447 crashed into the Atlantic Ocean, it took search teams two years to find and raise the black boxes. They provided valuable information about what actually happened prior to the crash.

The US Navy has sent a Towed Pinger Locator (pictured above) to help with the search for MH370’s flight data recorders. The locator is used for finding emergency relocation pingers on downed Navy and commercial aircraft at a maximum depth of 20,000 feet anywhere in the world.

7. They’re virtually indestructible…

FDRs are usually double-wrapped in titanium or stainless steel, and must be able to withstand atrocious conditions. The crucial part that contains the memory boards, the CSMU, is shot out of an air cannon to create an impact of 3,400 Gs and then smashed against a target. It is subjected to a 227kg weight with a pin attached to it, which is dropped onto the unit from a height of three metres. Researchers try to crush it, destroy it in an hour of 1,100 degree Celsius fire, submerge it in a pressurised salt water tank, and immerse it in jet fuel.

8. … But they’re not as powerful as your phone

In the aftermath of MH370, experts say it might be time to update methods of collecting flight data. Passengers are able to text, stream and surf the internet but the data recorders on board are not communicating in real time with the rest of the world. However, the bandwidth needed to stream huge amounts of data from large aircraft is not currently feasible. Aviation author Stephen Trimble writes in the Guardian that Boeing has applied for a patent on a system that will transmit a subset of data including the plane’s location:

There will be costs to mandating such a system, but the benefits are clear. Multi-national search and recovery teams involving a fleet of ships and search aircraft should no longer be necessary. Critical safety data could provide clues of system or structural failures much faster, making the entire air transport system safer.