Just received this email from a friend I worked with at Boeing. Its an article from the International Herald Tribune on the Greek Boeing 737 crash.

What I find hard to understand is that even with the confusion over the warning horn, at 14,000 feet the oxygen masks dropped. That should end any confusion as to what the warning horn is for...

JoeA

Following article is from Don Phillips of the International Herald Tribune on the sad story of the Helios accident. Thought you might be interested.
************************************************** ******************

By Don Phillips

PARIS: The crew members of a Cypriot airliner that crashed Aug. 14 near Athens became confused by a series of alarms as the plane climbed, failing to recognize that the cabin was not pressurizing until they grew mentally disoriented because of lack of oxygen and passed out, according to several people connected with the investigation.

Complicating the cockpit confusion, neither the German pilot nor the young, inexperienced Cypriot co-pilot could speak the same language fluently, and each had difficulty understanding how the other spoke English, the worldwide language of air traffic control.

A total of 121 people were killed in the crash after the plane climbed and flew on autopilot, circling near Athens as it was programmed to do until one engine stopped running because of a lack of fuel. The sudden imbalance of power, with only one engine operating, caused the autopilot to disengage and the plane to begin its final descent.

The Greek authorities have made cryptic statements hinting at oxygen problems but have so far not announced the full findings of investigators.

The people interviewed for this article agreed to do so on condition that they not be identified because none are official spokesmen for the investigation and because of political sensitivities arising from a Cypriot plane crashing in Greece.

Investigators pieced together the story of the crash from numerous sources. In the wreckage, they found the first solid clues--the pressurization valve and an air outflow valve set incorrectly. Air traffic control tapes provided information on the confusion in the cockpit. The plane had a sophisticated new flight data recorder that provided a wealth of information. There were maintenance records from the night before, and investigators interviewed the mechanics who worked on the plane.

Among other things, the investigators determined that the pilot was not in his seat because he was up trying to solve a problem that turned out to be not the greatest threat facing him.

The plane that crashed, a Boeing 737, underwent maintenance the night before. The maintenance crew apparently left a pressurization controller rotary knob out of place, according to the officials connected to the investigation, and the crew did not catch the mistake during preflight checks the next day. This meant that the plane could not pressurize.

At 10,000 feet, as designed, an alarm went off to warn the crew that the plane would not pressurize. However, the crew members mistakenly thought that the alarm horn was a warning to tell them that their controls were not set properly for takeoff, the officials said. The same horn is used for both conditions, although the it will sound for takeoff configuration only while the plane is still on the ground.

The crew continued the climb on autopilot. At 14,000 feet, oxygen masks deployed as designed and a master caution light illuminated in the cockpit. Another alarm sounded at about the same time on an unrelated matter, warning that there was insufficient cooling air in the compartment housing avionics equipment.

The radio tapes showed that this created tremendous confusion in the cockpit. Normally an aircraft cabin is held at 8,000 feet pressure, so the crew at over 14,000 feet would already be experiencing some disorientation because of a lack of oxygen.

During this time, the German captain and the Cypriot co-pilot discovered they had no common language and that their English, while good enough for normal air traffic control purposes, was not good enough for complicated technical conversation in fixing the problem.

The crew members called the maintenance base in Cyprusand were told that the circuit breaker to turn off the loud new alarm was in a cabinet behind the captain. The captain got up from his seat to look for the circuit breaker, apparently ignoring the confused co-pilot.

As the plane continued to climb on autopilot, the air grew so thin that the crew became seriously impaired. The captain passed out first on the floor of the cockpit, followed by the co-pilot, who remained in his seat, according to the officials.

The autopilot did as it was programmed to do, flying the plane at 34,000 feet to Athensand entering a holding pattern. It remained in a long circling pattern, shadowed by Greek military jets, until fuel ran low and one engine quit.

Boeing, the maker of the plane, issued a notice shortly after the crash to airlines that it would revise flight crew training manuals to stress to crews that they must understand how the various warning systems work and what to do about them.

The notice stresses that the takeoff configuration warning horn will not sound under any circumstances after the plane has left the ground. The same horn will then be used only for a cabin altitude warning. The company notice said there had been other instances of confusion over the horn by pilots.

"Confusion between the cabin altitude warning horn and the takeoff configuration warning horn can be resolved if the crew remembers that the takeoff configuration warning horn is only armed when the airplane is on the ground,'' the notice said. ''If this horn is activated in flight, it indicates that the cabin altitude has reached 10,000 feet.''

International Herald Tribune

Good article Joe.

So the CAWS system (whatever Boeing calls it) used the same horn, no wonder they were confused.

The lack of a common language is an egregious CRM failure. It is not, per se, a pilot error, however. It is a personnel issue.

The other CRM issue: focusing on the small issue when it's the big one that kills you. They must have thought the warning alarm was a nuisance trip of the CAWS configuration system and decided to silence the warning.

What really gets me is this: isn't there a cabin altimeter on the panel?

Didn't this same scenario happen a couple of decades ago when the flight crew became so focused on a warning light indicating that the nose gear hadn't locked into place that they allowed the plane to fly right into the ground? It seems like I remember the hearing the female voice on the cockpit voice recorder saying, "Altitude, Altitude" as the crew was discussing the warning light...

Mike

Mike,

It was an airliner that flew into the Everglades. They had a bad bulb on a landing gear indicator and the crew all concentrated on it while flying. One of the pilots accidently pushed on the control column and it disconnected the autopilot, without any indications. Airplane then began a gradual descent into the water...

We learned a lot on that one, now one pilot flies the plane, period and does nothing else.

Its a different world overseas, as is shown by the article.

JoeA

Yeah! That was it...

Good article, Joe.

And in your next post you mentioned the potential problems with a purely price-drive deregulated airline industry. As I've said before, I always appreciate your remarks. I'm personally no big fan of over-regulation. But I'm not so naive as to believe regulation-bad, deregulation-good. The telephone industry has been deregulated, with good news and bad news. It caused a capital infusion and rapid development of the technology. But it sure did not lower anybody's phone bill. In the airline industry, I'm not sure what good it did at all. That industry seems to be a race to the financial bottom. United Airlines bankruptcy proceedings included $3.6 trillion is creditor claims, and has achieved billions of dollars in employee wage concessions as they continue to struggle against liquidation. Northwest Airlines and Delta are similarly situated.

I'm sorry but there are juse some things that deregulated private business makes a mess out of. A safety-sensitive commodity-oligopoly like air travel is one. Electric power deregulation is another colossally bad idea.

I work at an airport and I also travel. And I am not wildly impressed by most of the players in the game. I'm just glad that the public owns the darned airports, and that the FAA still regulates aspects of air travel. I expect a smaller number of airlines in the future, at least if bankruptcy judges quit trying to save the dying ones. This industry's optimal configuration is probably a small number of very large carriers, with some smaller regional niche companies to serve markets the larger ones don't want. This will limit choice a bit, but it will also give the industry a chance at financial stability.

I know this has gotten off the track, but I really do think there have been some pretty negative forces working against air travel safety, and terrorists are actually low on that list. Deregulation is high on the list, and lack of adequate government infrastructure and oversight is too. In my view. Ladies and gentlemen, this is not what we want to regard as a "self-regulating market."

Here you go. Notice the green 'manual' indicator. This is on the overhaed at quite a steep angle...
http://forums.pelicanparts.com/uploa...1126281411.jpg

This is a 733...

Great photo. Certainly that's outside the normal scan.

What is a "pressurization controller rotary knob?"

Its the knob you use to set the landing altitude into the controller.

Agree that this may not be in a flight crews normal scan, but come on guys! When your ears keep popping faster than normal and then the O2 masks in the back deploy, its time to descend and stop fussing with anything else. Course I want to live to love and drive another day...

JoeA

True,friend of mine is Camera guy for a News Co.In Africa somewhere..he see's a guy in the dress up outfit doing meet and greet, oh there is another doing same..so ? is flying the plane...oh my, it seems the door shut itself...where is the ax's..thankfully it was an older plane and they were able to break back into the cabin.
Rika

I think it's a Boeing checklist challenge/respone though...
Gotta be a lttle tough when the two guys on the FD don't spaek the same language!

D,

I know this very well. I was based in Berlin for many years and as the senior (high flight time) pilot always got the junior guys to break in.

Europeans do it a lot differently than we do. They go to lots of school, then basic flying in a single engine. Then progress to something like a Beech Bonanza, a complex single. After this they fly about 20 hours in a Piper Cheyene, a twin turbo prop THEN are thrown into the right seat of a Learjet or Boeing and told "its all yours"! They have around 225 total flight hours at this time. Very good with the books but barely know how to fly the plane.

Needless to say, the Captain has his hands full and the first 100-300 hours the copilot is there to read the checklist and hold on. We had a bit of communication issues but more it was the total lack of experience. In the states the same copilot would have usually at least 1000 hours and more likely 2000+ hours.

In the end the Captain should not have left the cockpit, should have descended when the horn came on and both should have gone immediately onto the mask. They would have landed, with some scared pax (they always get that way when the masks drop) but alive and well...

One thing that is not mentioned in any of the reports is that I bet that both pilots were heavy smokers. I can stay awake at 14,000 feet with no problem and for both flight crew to pass out, something else is going on. Usually its due to heavy smoking ...

JoeA

Agree.
TOC at 140 still fairly long, but remember, they were still in climb! I'm sure CRM was a huge issue. Not being there it's hard to call but the rubber jungle should have been a whack in the back of the head!
Feel bad for the FA in the left seat who ran out of juice.

I read somewhere on the Internet that the max ROC below 10,000 is 4000 FPM. Above 10,000 to FL200, about 2200 FPM. Flatter after that. Depending on weight and atmospheric conditions, probably a little less.

But let's figure 2000 FPM from 10,000 to the terminal altitude of FL340. That's twelve minutes, if you don't count the three minutes at 160 (this posted by Singpilot in another thread)-- which should be confirmed by the radar/atc tapes? Not a ton of time, particularly with a distracted crew.

TOC at 180's something like 15-20 minutes, but could be cut in half by exertion (Captain) or physiological factors (Joe, you're right on with the smoking). At 400 it's like 15-20 seconds. So on average, let's call the TOC 10 minutes. Which is about what they had.

What still blows my mind is that the masks were supposed to drop at 9600 +/- 600. If they were actioning a supposed configuration warning nuisance trip by pulling the breaker, wouldn't there be any indication in the back of the cabin that the masks had dropped? Like a call from the FA?

Something still doesn't fit here.

John,

You are partially correct. The cabin altitude warning horn comes on at 10,000, and the masks drop at 14,000. Other than that, everything correct.

Agree with what you are saying about time of useful conscieness. Someone should have figured it out and one of them should have been the pilots.

Joe A