Here's an article by one of the journalists of the Cyprus Mail [from today's Internet edition] concerning a number of unanswered questions about the crash and the subsequent investigation:
Helios: the mysteries remain
By Elias Hazou
To the living we owe respect, but to the dead we owe only the truth
Voltaire
TO MANY in the aviation industry, the fact-finding report into last summer’s air disaster should not be treated as Gospel; it is not the absolute truth on what really happened on that morning of August 14 2005, when 121 souls perished in a ravine at Grammatikos, 50km from Athens.
An alternative theory cites the cause of the accident as an insidious, non-recurrent malfunction – or in plain English, a freak breakdown of the plane’s electronics.
As one airline engineer in Greece put it, “there are a lot of dark areas. I suspect we have a great deal more to uncover, if you look hard enough. There’s more to the tale than meets the eye.”
The source, who did not want to be named, told the Mail that from the outset he has had doubts about the official version of events.
Though he did not as yet wish to commit to a hypothesis, the source did not rule out the “X” factor.
According to the accepted wisdom, as told by the report compiled by the Greek accident investigating team, the primary cause of the crash was human error: the two pilots had failed to notice during checks before and after take-off that the "cabin pressurisation mode selector" was in the manual position. The data suggests that the Helios ground engineer had set the selector on manual the night before the flight, following a pressure leak test. Had the switch been set to automatic, it would have allowed the cabin to pressurise by itself.
After take-off, the plane did not pressurise and the two pilots failed to recognise "the warnings and reasons for the activation of the warnings", including a cabin altitude warning horn and the dropping of oxygen masks.
The steady loss of cabin pressure led to the onset of hypoxia (oxygen deprivation), causing the pilots and passengers to pass out. The jet flew on autopilot for hours before it ran out of fuel and smashed into the ground.
Helios, now known as ajet, has contested the findings. The company says it has conducted “extensive tests” showing it would be virtually impossible for a Boeing 737 to take off with the airflow valve at 14 degrees from the fully closed position, as Tsolakis’ findings contend.
From a purely technical standpoint, actual takeoff is feasible, Helios says, but the excessively high pressure generated inside the cabin once the engines throttled would have caused unbearable pain to passengers, whose eardrums would burst. Thus, it is inconceivable that no one would have noticed this discomfort and taken action to stop the takeoff sequence in its tracks. Speaking to the Mail, engineers and pilots confirmed this much was true.
What the embattled airline is suggesting is that an electrical glitch caused the decompression switch to malfunction. Therefore, the captain and his co-pilots were also later fooled by constant warning signs that developed shortly after takeoff. In short: neither their ground crew nor their pilots committed any errors or omissions.
On the other hand, the Tsolakis report cites incontrovertible evidence – from the Flight Data Recorder (FDR) and the NVM (Non-Volatile Memory, a memory chip that stores components’ settings) – that the airflow valve was at a constant 14 degree angle throughout the flight. Tsolakis concludes that the pilots themselves would have had no reason to set the valve to manual, so the setting was configured on the ground before takeoff. The Helios report even features photos of the celebrated decompression panel corroborating the FDR and NVM data. Case closed.
Or is it?
On September 7, 2005 The International Herald Tribune alleged that the plane's captain heeded the advice of maintenance officials on the ground to pull the fuse on the electrical alarm-signal circuitry.
The paper said this was strictly prohibited by the manufacturers' operating manuals for all airliners and that it was considered criminal negligence.
The FDR showed that at 06:12:38 h and at an aircraft altitude of 12 040 ft and climbing, the cabin altitude warning horn sounded. At 06:14:11 h, at an altitude of 15 966 ft, the Captain contacted the company Operations Centre on the company radio frequency. According to the Operator’s Dispatcher, the Captain reported “Take-off configuration warning on” and “Cooling equipment normal and alternate off line.” The Dispatcher requested an on-duty company Ground Engineer to communicate with the Captain.
According to a written statement by the Ground Engineer written immediately after the accident at the Technical Manager’s instruction, the Captain reported that “the ventilation cooling fan lights were off.” Due to the lack of clarity in the message, the Ground Engineer asked him to repeat. Then, the Captain replied “where are the cooling fan circuit breakers?” The Ground Engineer replied “behind the Captain’s seat.”
It is thought that Captain Hans Juergen-Merten misread the horn for a takeoff configuration warning. As this did not make sense – the sound can only go off while the plane is on the ground – he assumed this was due to a glitch with the horn. Which supposedly explains why he asked the ground engineer for the location of the circuit breakers.
Because of this assumption, the pilots’ troubleshooting was off the mark, and ostensibly they never stopped to think the horns were warning of a decompression problem, wasting crucial time as the plane climbed.
Our source said: “These initial exchanges between the captain and the ground have been overlooked. To my mind, they are critical.”
He explained that circuit breakers are the mechanism controlling aural signals (such as warning horns) on the plane. These are located behind the captain’s seat and to the left.
Once an alarm for a takeoff configuration warning sounds, it will not cease until action is taken. This involves either dealing with the issue (such as correcting the flaps before takeoff) or silencing the alarm by pulling the circuit breakers – which is not recommended.
Frustratingly, the Tsolakis report cannot verify or disprove whether the warning horns were on throughout the flight. The Cockpit Voice Recorder, which was badly damaged, only contained data from the last 30 minutes.
And there’s a good reason why pulling the circuit breakers is forbidden: the mechanism has two ports, one for the takeoff configuration alarm, the other for cabin altitude (read: cabin pressure). So it’s very easy to make a mistake and silence the cabin altitude warning – a very bad idea.
But the Captain had asked the ground engineer about the equipment cooling switch. This, our source says, does not make sense. The equipment cooling switch is located not behind the captain’s seat, but on the overhead panel. The switch has two selectors: Normal and Alternate.
“There are no circuit breakers for equipment cooling. There’s no question of resetting it, such as by pulling a fuse.
“In other words, what may have happened is that – perhaps through some miscommunication with the ground engineer – the captain pulled the fuse on the electrical alarm-signal circuitry, thus inadvertently silencing the cabin altitude warning.”
The source added:
“We can only speculate, of course. But to me, it’s far-fetched to say the pilots ignored all the alarms that were going off, that they did not for a moment consider the possibility of a depressurisation problem. Or that they failed to conduct checks, both before takeoff and after. Their handling of the situation seems childish – too childish. I don’t buy it.
“You have a German pilot who’s been called bossy and arrogant. Perhaps this is a convenient story – an unpopular, headstrong character who did not heed advice from his co-workers.”
Yet the Tsolakis report also seems to come short on another point. Under the section “Analysis”, the report summarily concludes that a combination of stress and carelessness led the pilots to commit a string of errors:
“Exacerbating this tendency (expectation bias) is the rarity with which switches (especially, and directly relevant to this case, the pressurisation mode selector) are in other-than-their-normal position. A pilot automatically performing lengthy verification steps, such as those during preflight, is vulnerable to inadvertently falsely verifying the position of a switch to its expected, usual position (i.e. the pressurisation mode selector to the expected AUTO position) – especially when the mode selector is rarely positioned to settings other than AUTO.”
This is the “meaty” part of the report, where one would expect the most scientific and substantiated examination of events. Instead, it falls back on conjecture and guesswork. Although this is not unheard of in air accident investigations, it does imply there are blanks.
Lastly, looking back to the fateful day, another mystery unfolds. Eyewitness accounts at the wreckage site said that bushfires flared up much later, at least an hour after impact.
On 19 August, the Athens News reported:
"‘As we looked over the cliff where the plane's severed tail stood in a cloud of dust, I saw scores of dead bodies scattered across the slopes of the ravine near countless smouldering pieces of wreckage from the plane,” local villager Costas Michas told reporters gathered at Grammatiko later in the afternoon. “There were small kids still tied to their seats like plastic dolls, body parts and clothing hanging from trees.” He could see that most of the bodies were still recognisable, because the bushfires that burned them only flared up much later, at least an hour after the eyewitnesses were removed from the scene.
“Some of them could have been rescued from complete 'cremation', if only we were allowed to carry them further up on the hillside,” Michas told the Athens News.
“There was the body of a little boy with a gushing wound on its head, lying by a bush halfway down the slope. I took the child in my arms to carry it up to the top of the cliff. But then security people ordered me to leave the body on the ground and clear the area at once. Later the fires broke out and there was nothing left of the child. I will never forgive them for this,” he said, referring to the police and army personnel that cordoned off the area for the rest of the day while the firefighting continued.
The head of the Grammatiko town council, Thanassis Papageorgiou, was also among the first to arrive at the crash site. “When I reached to the bottom of the ravine, I saw dead people everywhere but they weren't burned,” he stressed. “I could smell no jet fuel. There was no raging fire; only smoke from smouldering pieces of the plane wreckage scattered across the hillsides of the ravine. I immediately called the fire department on my mobile.”
The land-based firefighting units arrived at Grammatiko 30 minutes later but were prevented by police from approaching the crash site for another half an hour, Papageorgiou said. “By that time, the ravine was ablaze and required the full force of eight firefighting planes for several hours to put out the fire.”
Other accounts told of a sequence of “crackling” sounds being heard in the area shortly before the hilly terrain flared up – again, much later than the time of the crash.
Given that both the Boeing’s engines had flamed out and – according to witness accounts – there was no smell of fuel – what could have caused a major fire? Did all the people on board die on impact? Will closure – for everyone, but more so for the victims’ relatives – ever be achieved?
With additional reporting by Demetris Yannopoulos from the Athens News
Copyright © Cyprus Mail 2006