Airbus A320 crashed in Southern France

[Cagedh]

Well that is just wrong. Unsafe and illogical.

Mmmh, not really

There are some interesting arguments in this article (http://www.ainonline.com/aviation-news/aviation-international-news/2010-01-26/study-pilots-ignore-oxygen-regulations).

[bille1319]

Some similarities noted with LAM Mozambique Airlines Flight 470 with the a/c in a dive but not quite a vertical dive. I hope not. You don't expect that sort of thing in Europe.

[abdunbar]

Have heard story of Boeing windshield failure of both inner and outer panel. Windshield was bulging outward against air stream, pushed out by cabin differential pressure. there is a plastic layer between the inner and outer panel and this was deforming but windshield held. do not know the particulars but windshield was held in by the very strong structure surrounding it. In the past that structure has been aluminum.

is the structure surrounding Airbus A320 windshields metal or composite?

[Pace]

Reading todays papers or rather between the lines of todays papers :ugh: This would appear to be a depressurisation or un commanded severe pitch down which could not be controlled or some sort of structural failure which lead to an inability to stop the aircraft descending.

there are two things which would indicate incapacitation of the Pilot/pilots
Firstly the track of the aircraft was fairly straight which indicates it was under some control (autopilot) with no pilot intervention and secondly the lack of communication with ATC from the crew.

Had this been a structural or uncommanded rapid descent with alert crew there would have been plenty of time for the crew to have relayed their problem and the track would have unlikely been straight as the crew tried to regain control.
As the authorities have discounted foul play this has to be incapacitation which I hope is the case as those poor people would have known little about their impending fate I hope (( and that fact may give their poor relatives a small crumb of comfort.

Why the aircraft failed to level at 10K is another matter

[fflyingdog]

Once all the furore has settled i think the aviation industry should be looking at a solution for all the scrabbling around looking for CVR's FDR's amongst wreckage and start looking at a permament 'uplink' via ACARS .Its not going to be a perfect 'fix' but it would certainly be a step in right direction.Our MOC can inform us before the aircraft lands what is wrong even down to a valve taking too long to open close etc . I know cost is a factor but but if legislated then they would have no choice.Dont flame me i'm an engineer and would just like to see certain aspects sped up, even down to pin pointing the actual crash sight.

[busTRE]

At the high rate of descent and with the many mountains around it is likely that the GPWS alarm went off around FL100.
What would it do?
Disengage autopilot?
Pullup?

It would issue an alert and then a hard warning in all probability. The exact mode of warning would depend in circumstances. Doesn't do anything else at all. That's left to the pilots.

[HubertWilkins]

There are some interesting arguments in this article.


Only 21 percent of Part 91 respondents “indicated they always use oxygen when one crewmember leaves his duty station above 35,000 feet,” according to the survey; 10 percent reported occasional use; 25 percent rarely; and 33 percent never.

Thank you. The articles states that many pilots, unfortunately, do not follow the rule. Which is very worrying indeed. This does not make the rule a bad rule. It just points to how many pilots disrespectful of the rule we have out there. And that is not a nice thought.

[fox niner]

It will also be a testament to the quality of the windshield.

[Chronus]

Here is what the book says for emergency descent:

PNF PF
1. ST BELT ON 1. TURN ALT, PULL ALT
2. ENG MODE SEL IGN 2. TURN HDG, PULL HDG
3.ATC CODE 7700 3. PULL SPEED
4.ATC MAYDAY 4. SPEED BRAKE EXTENDED
5. PAX SYZ ON

Only action would appear to have been PF 1, suggesting rapid crew inacapacition. An event such as wind shield loss at 38,000feet would certainly be the most significant factor.
My question is whether the chance of recovery would have been greater in a non-fully automated cockpit environment.

[vapilot2004]

You don't set a rate of descent. You basically close thrust ( open descent on the Bus ) and then the Elevators control the speed that you have selected. Therefore the rate of descent will vary.

Agreed but there is no normal operational reason for an oscillation in the resulting V path.

[dicks-airbus]

From avherald

According to Finnish CAA in Finnish newpaper Helsingin Sanomat, the CVR has revealed crew was unconscious in the start of descent. So looks like Helios 2.

[abdunbar]

interesting article. Yes , aware of the complaints about sanitary issue. We were given wipes to clean the mask, first flight. Many did not like. I was a Captain and I expected compliance so I know that FO's had the mask on at least until I left the cockpit. Also even non-compliance forces a mental review by most? I am not going to wear the mask but lets see.... there it is, if i need it... then put it on, Altitude- spin down, FLCH, throttles close, speed brakes, turn, talk.

As for oxygen poisoning. Interesting, who knew. I had several years of military tactical jet flying. we had a rule, 100% O2 required from takeoff to landing. This one did get violated a little. Biggest issue was that on a long flight you used a lot of LOX, liquid oxygen. Not every base could recharge it, if there was lightning in the area they wouldn't. So, there was some mask dangling flying at medium altitudes that would give a cabin pressure around 10k, checking fingernail bed color, monitoring cabin altitude gage often. Also, 100% oxygen dries you out. But oxygen poisoning? We knew about hyperventilation and that risk is higher when using 100% oxygen. perhaps this is the poisoning?

[skytrax]

Whatever happened at FL380 it was extreme. So extreme that prevented the pilots from doing anything else but descending. If that was done with their intervention.
Aircraft couldn't be controlled otherwise they would have attempted an emergency landing somewhere away from that extreme terrain where it ended up.
They couldn't navigate or communicate. Only an initial reaction to aviate when the problem occured. I can only assume that they were both incapacitated or the aircraft was uncontrolable as soon as it started to descend.
This is what I make out of what is known so far. I wouldn't venture to speculate about the reason. That is yet to be established. I'm pretty sure the authorities have an ideea already.

[Pace]

PNF PF
1. ST BELT ON 1. TURN ALT, PULL ALT
2. ENG MODE SEL IGN 2. TURN HDG, PULL HDG
3.ATC CODE 7700 3. PULL SPEED
4.ATC MAYDAY 4. SPEED BRAKE EXTENDED
5. PAX SYZ ON

Aviate navigate communicate. There are items in there which appear to be the wrong way around?

[NigelOnDraft]

Agreed but there is no normal operational reason for an oscillation in the resulting V path. Have you ever heard of wind?

In a normal decent from cruise alt using OP DES the V/S will vary much as seen - if the HW drops off the V/S can increase beyond what one might deem acceptable and use a different mode (V/S, DES etc.)

[NigelOnDraft]

Aviate navigate communicate. There are items in there which appear to be the wrong way around? At a first glance, maybe so. But now split to PF/PNF and you'll see PF is prioritising flying,

For reason an Airbus pilot, and only an Airbus pilot will understand ;) the Speed Brake is well down the list, and for good reason. It needs to be extended slowly and carefully (watching PFD) else life will get interesting and counter-productive :sad:

[Skittles]

Agreed but there is no normal operational reason for an oscillation of the resulting V path

Yes there is. As already stated in open descent it doesn't maintain a V/S, it maintains a speed.

As an example, with a sudden headwind increase (and subsequent IAS increase), the aircraft will raise the nose to adhere to the selected speed target, reducing the V/S in the process.

In a normal open descent, especially in varying wind conditions (as would be completely expected around mountainous terrain) then the V/S will change significantly. It's not unusual for variations between 1000fpm and 4000fpm.

[MD11Engineer]

Wirbelsturm:
The BAC 1-11 failure was caused by the incorrect nuts being fitted into a window which was fitted to a pressurised hull from the outside!

The Airbus has interference fit windshields that are fitted from the inside and then sealed from the outside for exactly that reason if I recall correctly.

Not the A320s where I changed windscreens. They are fitted from the outside, same as the B747, B757 and B767. The only aircraft I worked on with windscreens fitted from the inside is the Boeing 737,but changing a windscreen there is a lot of work and takes time because one has to dismantle half the cockpit (liners and glareshield) to get access.

[Gerd53]

Loss of all hydraulics could explain a marginally controlled flight path. The 320 can be 'flown' with differential thrust and trim, correct?

No trim without hydraulic!

[Pace]

CVR data has been read. It seems structural failure (windshield? not determined yet)..It was quick... sound of cracks,but crew initiated emergency descent by autopilot and then they weren't heard anymore. Autopilot was on during whole descent, but disconnected automatically shortly before impact when GPWS alerts appeared."

If so the crew had an impossible task and the whole thing is very very sad ((

[busTRE]

Agreed but there is no normal operational reason for an oscillation in the resulting V path.

Yes there is. Not sure which but you're not sure of.

In an IAS/Mach Idle descent the VS and thus vertical path will vary with wind, temperature/density changes, vertical currents, IAS/Mach switchover and other factors. An Open Descent is always quite variable in terms of achieved profile.

[Cagedh]

@ HubertWilkins

The article is good. It sheds a light on the pros and cons of the oxygen rule under FAA. Even if wearing an O2 mask before de-pressurisation MIGHT have saved this flight, (We don't know anything yet) there are very good arguments to be made for the European rules concerning oxygen.

The fact that the majority of pilots, generally a very responsible group of people, seem to ignore this rule might be an indication that the rule might perhaps be wrong...

[averdung]

There were undoubtedly many calls to the acft. French ATC are known for being alert, especially near borders... they'll send you a couple friendly Mirage 2000s if you miss an entry time or forget to report when entering their ADIZ.

They were aware something was very wrong, but most likely powerless (and frustrated) witnesses, like Greek ATC in the Helios case.

[surfinJ]

Double windscreen failure seems remote unless it was caused by an impact.
It would also preclude any donning of masks much less A/P manipulation to start the descent. A slow failure that caused the crew to first start a descent out of precaution followed by something more catastrophic more likely.

[Bleve]

vapilot2004 says
You don't set a rate of descent. You basically close thrust ( open descent on the Bus ) and then the Elevators control the speed that you have selected. Therefore the rate of descent will vary.
Agreed but there is no normal operational reason for an oscillation in the resulting V path.

no normal operational reason for an oscillation in the resulting V path

In nil wind that would true, but the real world is not like that. As you descend (or climb) the head/tail wind component will change. That will change your IAS and if you have select a 'pitch for speed' mode, the pitch attitude (and thus the V/S) will change to maintain the selected speed.

[Capt Kremin]

Below are the IAS approximations taken from groundspeed readouts from FR24 for the flight. They were taken as a TAS and converted to an CAS, therefore they are not corrected for wind effect. There was a southerly blowing at around 13 knots in the lower levels, rising to about 30 knots in the higher levels.

I don't know how closely these correspond to the actual IAS considering all the possible errors and the fact that the aircraft was descending rapidly, however...

VMO/MMO for the A320 are 350 knots/0.82

32625 CAS 296 EAS 279 MN .823

28875 CAS 313 EAS 297 MN .805

24650 CAS 343 EAS 328 MN .81

20300 CAS 358 EAS 345

17000 CAS 355 EAS 345

15000 CAS 355 EAS 346

13300 CAS 358 EAS 351

11125 CAS 355 EAS 349

9975 CAS 350 EAS 345

8259 CAS 342 EAS 339

6925 CAS 343 EAS 340

There remains the strong possiblity that the hi speed protections activated during the descent. They activate @VMO +6

Normal Law - High Speed Protection

When high speed protection is active:

The autopilot disconnects

High speed aural warning is heard

Automatic pitch trimming stops

Bank angle limit is reduced from 67° to 45°

Positive spiral static stability is introduced to 0° bank angle (instead of 33° bank angle in normal law), so that when the side stick is release it always returns to 0° bank angle instead of 33° bank angle

High speed protection can be overridden, but side stick nose-down authority is reduced and a positive pitch-up command is introduced

If the stick is released, the airplane continues to pitch-up until the airspeed slows to VMO/MMO at which point the high speed protection is deactivated and normal control laws are restored.

The questions are whether this aircraft went fast enough to activate the high speed protections? If it did, why didn't it pitch up, and what was it doing flying so fast in the first place?

If pilot incapacitation occurred, why did the Auto-pilot maintain maximum possible speed, and why did it not capture an altitude selected on the FCU?

The standard drill for an emergency descent involves keeping the autopilot engaged if possible, dialing a lower FCU altitude, turning off the airway and commencing the descent by selecting Open Des.

The aircraft continued on track but commenced descending at maximum speed, so none of that appears to have been done. Unless there was a massive un-correctable error in the Auto-flight system, there had to be pilot intervention to get it to do that.

This is a very strange accident.

[NigelOnDraft]

If it is a fwd fuselage structural failure (e.g. windscreen) the investigators, I think, will have their work cutout :ooh: A high speed impact into a steep rockface will likely leave much evidence destroyed, and the chance of finding anything under the original failure point small, but possible. The crash site will be very hard to confirm "things not found" were never there and thus missing prior the crash.

The 14K V/S indication in the short cruise I'd be interested in a technical explanation of how/where it has come from? Mode S? Where does ADS-B get (or derive) this from?

[ATC Watcher]

There were undoubtedly many calls to the acft.
yes, a lot .
Last normal communication from the crew was one min before start descent.
then nothing.
It is quite traumatic for a controller I can tell you when you watch an aircraft you control go down.

[Pace]

The standard drill for an emergency descent involves keeping the autopilot engaged if possible, dialling a lower FCU altitude, turning off the airway and commencing the descent by selecting Open Des

If your not incapacitated or your brain isn't so scrambled that your inputs are as to the book ?

[Chronus]

Yes Nigel, the disposition and fragmentation of wreckage will undoubtedly make the task of indentifying the windshield and whether it was separated prior to impact. However in the event that it did blow out at 38,000feet, then as the aircraft commenced a descent just about when it was coasting in, then the evidence will be lying either in the water, close to shore or further inland, not with the main wreckage.

[darkroomsource]

Full Quote from Avherald

FORUM SECTION

Anonymous posting here:

http://avherald.com/h?article=483a5651&opt=0

Structural failure
By Uknown on Wednesday, Mar 25th 2015 09:01Z

CVR data has been read. It seems structural failure (windshield? not determined yet)..It was quick... sound of cracks,but crew initiated emergency descent by autopilot and then they weren't heard anymore. Autopilot was on during whole descent, but disconnected automatically shortly before impact when GPWS alerts appeared.

Again!
FORUM SECTION, referring to an "anonymous" post, on another FORUM


All this conjecture.


People, STOP the conjecture. Until the investigation is done, NO-ONE will know what happened.

[cirr737]

BEA has some pictures of the CVR here:

Mediathèque (http://www.bea.aero/fr/enquetes/vol.gwi18g/mediatheque.php)

Memory unit seems to be in good shape

[NigelOnDraft]

Does anybody know if the correct level off altitude was 6800ft (as reported on some sites) or FL068 (as reported on avherald)?The "data" I saw from FR24 stopped at 6800', did not "level at". Systems showing it levelling off may well be "predictive" when the data stream is lost?

AvHerald had someone deduce an accurate crash location which my Google Earth makes ~5500'. The ridge beyond it GE says is ~6100'. Very roughly, if you take the last FR24 position, the RoD then, and run forward to the crash site, another 1000'-1500' lost is "in the ballpark" (I've not spent a lot of time on this, so do not treat with much confidence).

As I said above, if it was an OP DES descent, the selected Altitude (which the AP would level off at) should have been transmitted over Mode S the whole way down, so the BEA may reveal that later today?

[aviator17]

FL 100 set maybe but a/c unable to level off with A/P disengaged!

[HubertWilkins]

@Cagedh
Just to be clear, we are talking about the US rule which states:
if one pilot leaves the cockpit at XXX level, then the remaining pilot must don O2 mask and keep it on until the other pilot returns.

I guess we can agree to disagree, I believe this rule is sensible.

If there are two pilots in the office and decompression occurs, there are two heads trying to solve one issue. decent odds.
If only one guy is there the odds are halved, so it is good sense to have a head start.
That is what I believe.

[jdsworld]

The 14K V/S indication in the short cruise I'd be interested in a technical explanation of how/where it has come from? Mode S? Where does ADS-B get (or derive) this from?

The ADS-B transmissions include altitude and speed, direction amongst other information but do not give v/s. I believe the -14k V/S is a blip from FR24 processing as I'm sure it showed the same altitude of 38k before and after this event.

[Kubalson]

http://wstaw.org/m/2015/03/25/CA8MlqyUUAEXKOp.jpg

[skippybangkok]

If it were a windshield failure @ FL380, it would be extremely violent. Question would be how long till they recover from the shock, and whether ie Oxy masks can be found quickly or dislodged ?

[Pace]

People, STOP the conjecture. Until the investigation is done, NO-ONE will know what happened.

This is predominantly a professional pilots forum? It may have changed so that every Tom Dick and Harry can input into it but whether its a single engine Piston where a family of four have been killed or an Airline where many souls are lost talking about possible causes is beneficial.

Why? because with all these tragic accidents information and lessons learnt are best taken in when the horror and impact of the accident is fresh in pilots minds.

Sadly a year down the line when the AAIB reports are released the event is long forgotten.

Sadly even AAIB reports are not conclusive

Sadly some accidents remain a mystery (Malaysian airline) and the reasons will Never be found.

As long as posters do not post as FACT and do so responsibly discussing the possibilities can only be educational and positive.
No one can turn the clock back but we can look forward

[threemiles]

Does anybody know if the correct level off altitude was 6800ft (as reported on some sites) or FL068 (as reported on avherald)?

ADS-B data is always QNE (=1013mb)

Anybody who wants to analyze ADS-B data go to the FR24 twitter page, then load the csv data file with 7,900+ data points to Excel. Packet interval is 1 sec and less. Apply an auto filter to receiver 1418. This receiver has continous uncorrupted and consistent data until the final packet. http://www.pprune.org/rumours-news/558654-airbus-a320-crashed-southern-france-9.html#post8914431

If you filter other receivers you can see that some deliver nonsens and must be ignored. The -14,000 fpm tale V/S is not present on FR24, it must be a different source. Note that Flightaware and Planefinder do not have as near as many receivers in the area as FR24.

[Bleve]

kbrockmanA catastrophic front wind shield failure could/would likely be immediately fatal for the pilot sitting behind it, I would imagine.

Ummmm - no. As the BA BAC111 incident shows, a windscreen failure has the windscreen blowing out. In that incident the Captain's windscreen failed, positive cabin pressure blew the windscreen out and sucked the Captain half out of the aircraft. Fortunately his feet snagged on the instrument coming which prevented him being completely sucked out of the aircraft. Fantastic flying and CRM from the F/O (well before CRM was even invented) had the aircraft safely on the ground with NO loss of life. The Captain survived.

[CargoFlyer11]

Germanwings to cancel more flights as crew members refuse to fly (http://news.yahoo.com/germanwings-cancel-more-flights-crew-members-refuse-fly-070537852--finance.html)

Germanwings will have to cancel more flights on Wednesday as some crew members refuse to fly, a day after an Airbus A320 operated by the budget arm of Lufthansa crashed in the French Alps.

"There will be irregularities... There are crew members who do not want to fly in the current situation, which we understand," a spokeswoman for Germanwings said.

[trtj]

I am not a pilot, I work in sensortronics.

Is there anyone in the know that could shed any light on if TAWS (terrain avoidance) or GCAS (ground collision avoidance system) will one day become automatic? I know NASA developed a system for the usaf but I doubt if it's commercial yet. Obviously if unconsciousness was the issue by this point of proximity to terrain it wouldn't be much help which leads me to my next question...

Could the emergency descent procedure be initiated automatically by the A/P in case of sudden de-pressurisation? This would leave the pilots' with severely reduced mental capability only one task. Oxygen. It seems emergency descent is the only option in case of extreme pressure loss, so why not make the initiation phase (flt level, heading etc) automatic, and immediate. Obviously this would have to be a highly redundant sensor system as you don't want spurious pressure readings leading you into an unwanted descent!

[mcloaked]

The photos of the CVR show considerable damage - but presumably the central cylindrical section contains the data store? Does anyone know whether the data is stored in sold state devices or whether the unit on this aircraft has a magnetic tape storage medium? I have seen pictures of the CVRs from manufacturers' web pages but both types look quite similar.

Is there much difference in impact survivability of the two different types of CVR regarding data integrity?

[737only]

http://www.extremetech.com/wp-content/uploads/2014/03/voice-data-recorder-diagram.jpg

[jonathanhoey]

Non-aviator here (when I fly it's strictly as SLC) so please forgive me if this is a naïve question or one that has already been answered elsewhere.

But is there a strong reason (other than tradition/precedent/The Way Things Are) why the CVR only captures audio?

Seems to me that in this day and age, it would be hugely beneficial to accident investigators to have video evidence from the cockpit as well as audio. 1080p digital video cameras (eg GoPro etc) can be had at retail for tens of [dollars/pounds/insert currency] so on an industrial scale, it doesn't seem like it would be cost-prohibitive to put a few in the cockpit of each passenger ship.

Perhaps onboard video of an accident would have too much of a ghoulish appeal for the news media, if released/leaked? Or perhaps it's a matter of crew privacy - although if the video was wiped/recorded over on each new flight, and never left the aircraft except in the event of an incident, I wouldn't expect that to be any more of a privacy problem than the CVR audio that is currently captured.

[MrSnuggles]

Swedish media reports that CVR was found and damaged but BEA are in the process of salvaging it and rumours has it that there might be some data released from it as early as today (CET).

Reading through all pages this far, it would be likely that a surprising rapid decompression took place and the flight crew wasn't able to react in proper time.

Four things that bothers me.

1) That -14000 feet glitch. It just reminds me of Valuejet and the exploding tyre.

2) No comms from the cockpit whatsoever. O2 supply not working?

3) Controlled descent, most likely initiated from the cockpit.

4) Maintenance the day before. Many bad things have happened when maintenance have forgot even the smallest thing, like the turn of a knob (Helios).

[lapp]

P.S. If you need forced pressure O2, to breathe at 40,000', then the pax are in real trouble with their dainty little masks. Which just demonstrates that you are completely wrong. So please provide some evidence, or apologise.

Why should he. You are the only one here claiming that no forced pressure is needed at high altitude when wearing a mask. Other people provided much more complete and authoritative postings than your, and to these nobody objected. Go back and read them.

[igs942]

From the Daily Mail:


"The doomed Germanwings plane may have crashed because the windscreen cracked, causing a sudden drop in oxygen that rendered the pilots unconscious, it was claimed today.
Reports circulating on professional pilot forums suggest the black box on the Airbus A320 has been analysed and reveals that a 'structural failure' was responsible for the disaster.
It is thought that the windscreen gave way, incapacitating the pilots and leaving them unable to send out a distress call."


Careful what you type guys and gals...

[neilki]

14 CFR 121.333 C (II)
"(3) Notwithstanding paragraph (c)(2) of this section, if for any reason at any time it is necessary for one pilot to leave his station at the controls of the airplane when operating at flight altitudes above flight level 250, the remaining pilot at the controls shall put on and use his oxygen mask until the other pilot has returned to his duty station."

Operators can also supplement this by requiring a CC seated in a jump or crew seat per approved sop

[MrSnuggles]

In answer to jonathanhoey:

One extra thing to certify for high altitude use, electrical wires being drawn, and so forth. Here, on firma terra we don't realise how hostile the environment is outside the airplane. Think Mount Everest and double that. You wouldn't think your gopro worked there, right? Besides that, many pilots feel it's a very palpable breech of their privacy. If you work at an office you wouldn't like your boss to know Every. Little. Detail. about what you do, right?

And for FDR/CVR streaming... I can only say bandwidth, Bandwidth, BANDWIDTH! We need about double the amount of space crap than is already up there for these streaming wishes to come true.

I do hope that all airlines realise the need for ACARS and/or engine monitoring since the MH370 disappeared though.

[pbeardmore]

A very high percentage of Mail readers will interpret that as fact. Sad how stuff circulates so quickly without verification etc

[GlenQuagmire]

Emergency Descent Mode is available and fitted on my current aircraft - I wondered if it was fitted or an option on the Airbus but judging by the comments on here, I don't think it is. On my aircraft it sets up the descent and turns off the airway - does everything apart from open the speedbrakes in fact. I saw the descent rates achieved by this aircraft and I'm assuming the rates indicated that the speedbrakes probably weren't open - can anyone who's current on the airbus confirm that? Could that indicate that a potential incapacitation happened very early on?

I hate the speculation and my only reason for writing this is a faint hope that all on board were unconscious or so hypoxic that they didn't have too much time to contemplate their fate. Recent times have been very tough in aviation and I'm off to work this afternoon thinking of all the families and friends of the people who boarded that aircraft.

Please can we all remember that they will be very likely to find these pages and read them, looking for answers.

[Founder]

@trtj

Any automated system relies heavily on sensor data and any manufacturer could probably not guarantee that a cause of a de-compression would not damage the sensors needed, which is one big reason why pilots still sit in those chairs in the front. Automated systems has a tendency to work well in controlled environments, when the aircraft is out of that environment it takes a bit more free-thinking system (pilot) to get the aircraft out of it.

Lets say that you have a de-compression because of a broken cargo door, it could very well destroy the AOA sensors which are located close by. How would the autopilot be able to fly the aircraft without one of the AOA sensors, which level of integrity of the system could the manufacturer guarantee?

As for automated terrain-avoidance it has already been seen that automated systems react in ways they were not designed to. For example radio altimeters reading the aircraft as if it was at 20 ft rather than 2000 ft and there by putting the engines into idle causing the crash of the Turkish B737 in AMS. This type of false sensor data is well known to cause failures of many automated systems on many types of aircrafts.

Automated procedures are nice, but in emergencies we need to realize that engineers can not develop systems which will save the aircraft out of every thinkable scenario. At some point the pilots need to do their work and perhaps manufacturers should design a better safety environment for the pilots in order to better shield them from a sudden change in the environment onboard?

[Denti]

14 CFR 121.333 C (II)
"(3) Notwithstanding paragraph (c)(2) of this section, if for any reason at any time it is necessary for one pilot to leave his station at the controls of the airplane when operating at flight altitudes above flight level 250, the remaining pilot at the controls shall put on and use his oxygen mask until the other pilot has returned to his duty station."


Quotes like that do not help at all. Remember that the aircraft was not flying according to FARs and that rules regarding oxygen use are very much different in euroland. European airlines simply do not fly according to FAR 121, that is a local rule in the USA, whereas in europe a multinational approach is used under the legislative rulework of the EASA.

[mcdude]

Could the emergency descent procedure be initiated automatically by the A/P in case of sudden de-pressurisation?

Airbus have been working on a concept like this for a number of years, but current status unknown. It is a complex concept to address because of the multiple sensor & system inputs. Maybe this event will provide a catalyst for change?

[igs942]

This is what I was asking a number of pages back. Airbus were certainly considering it for the A350. I was asking if it had been implemented as cannot find the definitive answer online.

[Bleve]

lapp:Quote:
P.S. If you need forced pressure O2, to breathe at 40,000', then the pax are in real trouble with their dainty little masks. Which just demonstrates that you are completely wrong. So please provide some evidence, or apologise.

Why should he. You are the only one here claiming that no forced pressure is needed at high altitude when wearing a mask. The other people provided much more complete and authoritative postings than your, and nobody objected. Go back and read them.

Maybe you should go back and read them. In my post dated 25th Mar 2015, 05:10 (currently #438) I explicitly stated that no forced pressure breathing is required up to 40 000' and gave exact technical reasons why. Every related post since then (up until yours) has supported this.

[Denti]

Business jets do have automatic descent for depressurization. But i don't know of any airliner that has that feature. Dunno why, but one reason might be the very different usage rate per year for airliners compared to business jets. We calculate with 3000 to 3500 hours a year for a narrowbody and around 6000 to 6500 a year for a widebody. From what i hear most business jets fly less than 1000 hours a year.

[threemiles]

Btw, have we ever heard from BEA what happened to Air Asia A320?

They were part of the investigation (though not in the lead). But how can it happen that 3 months after that accident we do not know about the cause WITH all recorders orderly retrieved.

What can we expect from BEA this afternoon and in this case?

[trtj]

@founder

Thank you for the reply. I guess there are just too many variables, sensor loops, and redundancy circuits to make a wholly reliable and viable single system that would do this.

[sp3ctre]

Besides that, many pilots feel it's a very palpable breech of their privacy. If you work at an office you wouldn't like your boss to know Every. Little. Detail. about what you do, right?

Sorry, I don't seem to have an option to quote people (unless I'm missing something)

MrSnuggles... This is pure presumption, but I thought the only time these recorders were accessed was after a disaster? Surely no contents of the CVR or a video alternative are accessible to "the bosses" on a routine basis?

[henra]

Business jets do have automatic descent for depressurization. But i don't know of any airliner that has that feature. Dunno why, but one reason might be the very different usage rate per year for airliners compared to business jets.

That's probably rather due to the fact that most current Business jets have much higher max ceilings (>/=50kft). At those altitudes TUC is practically non- existant, read zero. Therefore such devices are practically a necessity if you don't want to fly with pressurized oxygen mask in cruise and want to stand any chance in case of decompression.

[midiron]

I agree, but we should also talk and think about what is missing: signs of significant fire at the crash site. Even high-energy crashes like this will show signs of charring, more than the smoke here and there we are so far seeing. Why would that be?

[slf4life]

I find the concept of an automatic descent due to (insert failure scenario) , especially given the possibility of nonsense input which could trigger same, not a little disconcerting.

[henra]

Even high-energy crashes like this will show signs of charring, more than the smoke here and there we are so far seeing. Why would that be?

Good question. I haven't seen a trace of the Center Wing Box so far in the pictures. Nor a mark in the ground where it hit. In all previous cases of such frontal impact that I have seen pictures from there was a visible ground mark featuring the silhoutte of the aircraft to some extent. Maybe the main impact spot was outside of the areas shown in the pictures in detail.
Additionally, Engines at flight idle for 8 minutes will have cooled them down significantly. Maybe that also contributed to no major ignition.

[demomonkey]

TRTJ said:

I am not a pilot, I work in sensortronics.

Is there anyone in the know that could shed any light on if TAWS (terrain avoidance) or GCAS (ground collision avoidance system) will one day become automatic? I know NASA developed a system for the usaf but I doubt if it's commercial yet. Obviously if unconsciousness was the issue by this point of proximity to terrain it wouldn't be much help which leads me to my next question...

Could the emergency descent procedure be initiated automatically by the A/P in case of sudden de-pressurisation? This would leave the pilots' with severely reduced mental capability only one task. Oxygen. It seems emergency descent is the only option in case of extreme pressure loss, so why not make the initiation phase (flt level, heading etc) automatic, and immediate. Obviously this would have to be a highly redundant sensor system as you don't want spurious pressure readings leading you into an unwanted descent!

Emergency descents are not triggered automatically. Very few things are automatic and rely on pilots to know their memory drills well. Some newer aircraft have the ability for automated TCAS responses (e.g. A380). None (I know of) have automated TAWS, I guess that is because false TAWS alerts aren't unknown.

I think a lot of the reasons things are not automated is because incidents tend to happen in the grey areas where there are complex failures where simple (consistent) solutions may not always be the best option. That's why the Captain is a crusty old sort with millions of hour experience, who is able to use his/her professional judgement to save the day.

[silvertate]

Lapp

You are the only one here claiming that no forced pressure is needed at high altitude when wearing a mask. Other people provided much more complete and authoritative postings than your, and to these nobody objected.

But he is still wrong. Take a look at this Embraer 145 manual, using the standard Eros oxy system.

.. Only normal (N) oxy selection is required for all flight conditions, and it is normally diluted.
.. Above 33,000' the mask auto switches to 100% oxy.
.. (The valves sense the pressure. Note that it says if there is a depressurisation the mask will auto revert to 100%.)
.. There is a backup manual 100% switch, if you require.
.. But constant flow (emergency selection) is only required to prevent the pilot breathing fumes.
.. (That is why it is called 'emergency selection', and not the 'above 35,000' selection'.)

This is what our system says too, if I can find the book...

http://www.smartcockpit.com/docs/OXYGEN_E1.pdf

Again, if you have a reference that says something different, then please provide it.

[wiggy]

What can we expect from BEA this afternoon and in this case?

Press conference due this PM.

In the context of the supposed AVHerald comments re windscreens and CVRs the ex-head of BEA on French TV making great pains to point the protocol for handling the CVR and that it's unlikely at this stage (midday, 24 hours after the accident) that anyone has actually listened to it.

[FE Hoppy]

the_hawk how probable is it for pilots to regain consciousness during descent (when reaching appropriate flight levels)? does it depend on the duration of unconsciousness

Depends on the time and altitude both at alt and at lower (recovery) altitude.

[FE Hoppy]

silvertate

Read TSO-C89 (ETSO-C89 in EASA) and CS-25 for the standards required.

If the aircraft is certified to cruise above a certain altitude it has to be fitted with pressure breathing regulators to meet the required pressure and flow rates.

I'm not going to copy paste but if you really want to know you will find them.

[aterpster]

demomoney:

Emergency descents are not triggered automatically.

They are in some high end business jets if the crew doesn't take action and the cabin altitude rises above a prescribed value.

[Founder]

@trtj

The idea that a system can be created that could save an aircraft out of any thinkable emergency situation is a dream come true, to me that sounds like Artificial Intelligence that knows where it is, whats happening to it and also be able to adapt to it in order to save itself and not just rely upon pre-programmed commands.

I have no doubt that it will one day show up on the market, but I also think it'll take a very long time before we get there...

Autoland was developed and implemented in the 60's and aviation has still not perfected even that. I have had several unsuccessful autolands where we, the pilots, had to take over because the system could not cope with the sudden changes in environment such as downdrafts sudden change in crosswind etc.

[MrSnuggles]

To sp3ctre:

MrSnuggles... This is pure presumption, but I thought the only time these recorders were accessed was after a disaster? Surely no contents of the CVR or a video alternative are accessible to "the bosses" on a routine basis?

This was the gist for installing the CVR in the first place. Sadly, there are a few companies that sometimes use the CVR and FDR data to monitor pilots' performances and attitudes towards the employer/the job/etc so while it is not a standard procedure, there has been instances where "the bosses" have been poking around even though no accident has occured.

[AfricanSkies]

This bothers me. Here we have a flyable aircraft with an incapacitated crew. A CLEVER aircraft full of computers. It knows it's cabin altitude and it's altitude. It's got a terrain database. It's got a GPWS. It can tell if it's been suddenly depressurized. It's under control. But it can't automatically fly itself down to a safer altitude and then avoid terrain on autopilot?

Same as AF447. The aircraft KNOWS it's got a great chunk of weather in front of it. It should be expecting turbulence and icing and prepare itself for possible associated problems such as temporary loss of airspeed sensors.

In November a 321 relied solely on aoa info and dived the plane down. What about crosschecking with Inertial input and GPS input? Again, half a job of automation.

The systems people need to widen their view and concentrate not just on the minutiae of up down left and right but on the big picture.

[Founder]

@aterpster

Could those systems be in place in those aircrafts because TUC (Time of Useful Consciousness) is so short at the altitudes where those aircraft operate?

Manufacturers could load those aircrafts with billions of systems, but in the end who is going to pay for it? The customers doesn't seam to be interested in doing that... they're not even willing to pay for reasonable contracts for the employees onboard...

[ams6110]

Besides that, many pilots feel it's [cockpit video] a very palpable breech of their privacy. If you work at an office you wouldn't like your boss to know Every. Little. Detail. about what you do, right?

Many folks are on video recording at work at all times. Cashiers, bank tellers, etc. in particular. And they are only responsible for a bit of cash, not hundreds of lives.

[Hiflyer2010]

This button has been disabled on all A320-FAM A/C at DLH since before 2000, because of possible inadvertent high descent rate if used unintentionally.

Only a few old A319s at GWI still have this button... But definitly not D-AIPX

[flyonthewall]

If they lost a windscreen, they'd get a 400kt blast in the face of air at -40C or so.
Getting your mask on and establishing comms as per the checklist would be challenging to say the least. They may have initiated the descent but a 400kt breeze could easily rip the mask off your face. The noise would preclude any communication either in the cockpit or with ATC.

It would be a terrifying enough scenario without considering the possibility of potentially fatal consequences if the windscreen, or parts of it, came back into the cockpit. The cold air and wind may cause you to keep your head down below the coaming. If that was the case, you may not recover in time to look up and see the mountains looming large...

[silvertate]

Hoppy


Read TSO-C89 (ETSO-C89 in EASA) and CS-25 for the standards required.

If the aircraft is certified to cruise above a certain altitude it has to be fitted with pressure breathing regulators to meet the required pressure and flow rates.


Yes, and this document says that the max altitude for diluter-demand oxy systems is 40,000 ft. And for simple pressure systems, up to 45,000'. As I said, the normal (N) diluter-demand setting is good for all altitudes, unless you are above 40,000' which this aircraft was not. So your point is?

https://easa.europa.eu/system/files/dfu/CS-ETSO.pdf

[fireflybob]

As a pilot I would have no objection to being videod whilst on the flight deck so long as this data is only for accident investigation and it will not be in the public domain.

When CVRs were first mooted in the UK the pilot unions and indeed the regulators I believe would only accept the idea being mandated so long as the actual recordings would notappear in the public domain although transcripts of conversations in accident reports would be acceptable.

[AirScotia]

Quite apart from the autopilot flying the plane, I don't believe I've heard of automated communications facilities - ie, the plane's computer generating radio messages in an emergency situation? It's producing synthesized voice inside the cockpit - is there no value in it broadcasting 'Emergency: depressurisation!' to ATC or nearby aircraft?

[lapp]

But he is still wrong. Take a look at this Embraer 145 manual, using the standard Eros oxy system.

.. Only normal (N) oxy selection is required for all flight conditions, and it is normally diluted.
.. Above 33,000' the mask auto switches to 100% oxy.
.. (The valves sense the pressure. Note that it says if there is a depressurisation the mask will auto revert to 100%.)
.. There is a backup manual 100% switch, if you require.
.. But constant flow (emergency selection) is only required to prevent the pilot breathing fumes.
.. (That is why it is called 'emergency selection', and not the 'above 35,000' selection'.)

This is what our system says too, if I can find the book...

http://www.smartcockpit.com/docs/OXYGEN_E1.pdf

Again, if you have a reference that says something different, then please provide it.

I have read the references and relates postings and must say that what you say is correct. Notwithstanding, it is my totally personal opinion, that setting "EMER"for mask breathing at FL 380 can't do nothing but help breathing. Would you elaborate on the possible negative consequences of doing that.

[silvertate]

Good question. I haven't seen a trace of the Center Wing Box so far in the pictures. Nor a mark in the ground where it hit.


Sorry, this is a non-starter. They did a test of an F-4 Phantom hitting a nuclear power station concrete wall at 500mph, and the jet just disappeared. I won't post it here.

[GearDown&Locked]

By the look of things, whatever happened, prompted the crew to leave cruise alt immediately, but left the crew incapacitated in seconds, as they couldn’t execute any logical subsequent actions, to save their pax (and their own) lives.

Rapid decompression due to structural failure (or even a collision with some FOD dropped from another passing plane) could explain this scenario.

One of the possible keys to unlock this mystery is the reaction of the pax and cabin crew; in 8 long minutes, were there any attempts made to call or text somebody? Or the event that rendered the crew incapacitated also affected the pax and cabin crew at the same time?

[B772]

An aerial photograph released by AAP appears to show the cockpit cab generally intact if I am not mistaken.

[bartonflyer]

...... The noise would preclude any communication either in the cockpit or with ATC....

But presumably would be pretty obvious on the CVR?

[Aeromar27]

Decompression has been ruled out by GermanWings. This leaves me completely clueless.

[Wrist Watch]

This bothers me. Here we have a flyable aircraft with an incapacitated crew. A CLEVER aircraft full of computers. It knows it's cabin altitude and it's altitude. It's got a terrain database. It's got a GPWS. It can tell if it's been suddenly depressurized. It's under control. But it can't automatically fly itself down to a safer altitude and then avoid terrain on autopilot?
Automation does not imply artificial intelligence. You're blaming a mindless machine... If someone is to be blamed, it is manufacturers, Thales, Honeywell, and Rockwell Collins.
Autopilot works on the principle of a computer - you tell the computer what you want it to do in each situation you program it for. It doesn't figure it out on its own.
If your point is "current air navigation / flight management systems are outdated", I'd agree 110%. There is so much more potential but not enough initiative. Or money.

[PlaneMass]

@wigyori: Good points, thanks. I see what you're saying about retail/industrial, and I wasn't quite suggesting that the airlines just pop down to the shops and buy a few GoPros off the shelf for each craft ;) But nonetheless the technology is getting better and cheaper all the time, and one would imagine that principle would apply on an industrial scale just as it does in the consumer market, even if the actual numbers are higher. There's no technical reason why video recording equipment could not be fitted, and data recorded in a similar way to how it's done with the CVR.

The pilot unions have been against this for years though on the grounds of privacy.

[Tigger_Too]

This explanation might possibly help the oxygen debate:

"At 10,000 ft the partial pressure of the oxygen in the lung reaches 80 mbs. This is the minimum that a healthy person can tolerate and accordingly, above this height, the first symptoms of lack of oxygen, or hypoxia, appear. Between 10,000 and 15,000 ft the ability to perform skilled tasks such as aircraft control and navigation are impaired while between 15,000 and 20,000 ft there is a marked deterioration of performance, even of simple tasks, together with a loss of critical judgment and willpower. Thinking is slowed while muscular incoordination and clumsiness result. Above 20,000 ft the symptoms become severe, rapidly leading to unconsciousness.
The onset of hypoxia can be delayed by increasing the proportion of oxygen in the inspired air with the result that the partial pressure of oxygen in the lung is increased. Assuming that the pilot is breathing 100% oxygen, then the partial pressure of oxygen in his lungs will not fall below 130 mbs until above 34,000 ft. Above this altitude, even when breathing 100% oxygen, the partial pressure of oxygen in the lung will reduce, and breathing 100% oxygen at a height of 40,000 ft is equivalent to breathing air at 10,000 ft. Above 40,000 ft, hypoxia can only be prevented by employing pressure breathing."

[the_hawk]

Decompression has been ruled out by GermanWings. This leaves me completely clueless.

source? press conference?

[seagull967]

More to do with the fact that a small pressure vessel will lose all the pressurization very rapidly. A large aircraft could lose a few cabin windows and easily hold the cabin pressure, not so of a corporate type jet.

[NigelOnDraft]

It does get one thinking about being caught outside. In the font loo, take a big gulp from the dropdown, hold your breath then scramble in. Down the back, grab one of the portables and take it with you... Post Helios, there are SOPs for crew to enter the Flt Deck. I cannot envisage any Flt Crew remaining in the toilet during a gentle extended descent?

[busTRE]

Well, fro staters, the fact that you're using your oxygen far more quickly than the design scenarios account for.

[EGLD]

Re: the discussions on automatic terrain avoidance, I find it incredible that an Airbus which can automatically ensure it is not flown outside of it's flight envelope can still be flown into terrain

No doubt the cockpit was full of blaring sirens, the radar altimeter knew (or thought it knew) what was happening, GPS knew where they were, and yet the aircraft seems to have flown straight into a mountain

Assuming these things can be manually overridden, and accepting nothing is infallible, I've seen no explanation yet as to why it wouldn't be better for the aircraft to halt it's descent and possibly climb if it thinks it's about to fly into terrain with landing gear not down, and perhaps even inititate a transponder code to indicate it has just manually intervened and the pilots may be incapacitated

I would wager most SLF would gladly fly on an airline that implemented such a solution

[susier]

Germanwings crash: Evidence points to mechanical failure, say experts | News | Travel Trade Gazette (http://www.ttgdigital.com/news/germanwings-crash-evidence-points-to-mechanical-failure-say-experts/4695632.article)


This may be the source that Aeromar was referring to wrt decompression being 'ruled out'.

[LTETristar]

I notice that although almost of the plane seems to have been reduced to tiny fragments (according to media coverage so far), the large section showing the D-AIPX registration survived intact, and landed face up; a useful design feature.

[deefer dog]

I'm not going to speculate, but as rapid decompression has been discussed, here is my tuppence worth.


Irrespective of what many here have stated, and despite how many times you practice in the sim, a rapid decompress at or above FL400 is certainly going to present any pilot with a major challenge. You can forget the procedure we are all ready for while sitting in our nice warm sim every six months, because the first sign of anything abnormal in real life is 100% for sure going to scare and confuse the cr@p out of you (quite probably, literally). There is one video posted previously that illustrates this very well....the pilot, who was fully prepared for the event, sat for about three or four seconds like a startled rabbit, and following this was unable to get his mask on without assistance. Again, this was someone who was fully ready and prepared to do only one thing....get his mask on!

It surprises me that some here are not able to imagine the physics behind what happens - all air suddenly expelled from your lungs, eardrums, and bodily cavities, and finding oneself shocked by the dramatic temperature reduction, terrible noise, fogged air and debris flying around the cockpit. Total confusion doesn't even begin to describe the state most of us would be in.

I would even go so far as to state that as airliners are now cruising at higher and higher levels compared with 30 years ago, a re-think on the rules is needed to get this uncomfortable elephant out of the room.

[Discorde]

I find the concept of an automatic descent due to (insert failure scenario) , especially given the possibility of nonsense input which could trigger same, not a little disconcerting.

Agreed. Over the ocean auto descent after pressurisation failure might be useful but in busy European & US skies a plummet without some sort of ATC clearance could lead to more serious consequences. A mid-air would clearly be more hazardous than temporary hypoxia for some passengers.

[Aeromar27]

Quote:
Decompression has been ruled out by GermanWings. This leaves me completely clueless.
source? press conference?

Philippa Oldham, Head of Transport at the Institution of Mechanical Engineers

I don't think it makes sense though as I don't think she has more information than the rest of the people not involved in the investigation do.

[Pace]

How on earth could they rule out depressurisation and crew incapacitation? There is no basis to do that at this stage.

they would have had 8 minutes to have made ATC aware of a control problem yet made no contact?

The aircraft flew in a straight line surely any pilot faced with such a situation would try everything to gain control which would make it extremely unlikely that the aircraft would fly a straight line.

Every indication points to the pilots being incapacitated and the autopilot holding the aircraft on a heading and nothing to two alert pilots trying to control or regain control of an aircraft

[dicks-airbus]

Germanwings crash: Evidence points to mechanical failure, say experts | News | Travel Trade Gazette (http://www.ttgdigital.com/news/germanwings-crash-evidence-points-to-mechanical-failure-say-experts/4695632.article)

I fail to see any "evidence" here. Another BS article.

The aircraft flew in a straight line surely any pilot faced with such a situation would try everything to gain control which would make it extremely unlikely that the aircraft would fly a straight line.

Either they were incapacitated or unable to stop the decent due to mechanics. Both options point to a mechanical failure. As soon as the FDR is found and read we may know more.

[NigelOnDraft]

Assuming these things can be manually overridden, and accepting nothing is infallible, I've seen no explanation yet as to why it wouldn't be better for the aircraft to halt it's descent and possibly climb if it thinks it's about to fly into terrainSo long as you did not want to fly into Italy recently, where a spurious 8000' mountain appeared on the database for a while :{

Technologies are at various stages of development and maturity. You are trying to elevate airliners to the "Terrain Following Radar" of mil jets... IMO (E)GPWS is great for safety, but it is not yet robust enough to override a pilot.

[aterpster]

Founder:

Could those systems be in place in those aircrafts because TUC (Time of Useful Consciousness) is so short at the altitudes where those aircraft operate?

Indeed so. Of course one pilot is supposed to be on O2 at those altitudes, but we know how that one goes.

The other reason, I suspect, is the Payne Stewart (sp?) accident at the beginning of the century.

[STBYRUD]

Thats a rule for non-quick donning masks... Still exists.

[busTRE]

Tigger too

The point is that you need pressure oxy to sustain activity below 80mps. For shortish periods you can easily work efficiently above 10000 cabin alt. I have personally experienced 15000 in air tests with no obvious impact (not at controls I hasten to add). Thus it is safe to allow crew to operate to 45000 without pressure breathing equipment since they would experience the relatively small shortfall for only seconds as they started descent. Concorde at 65000 was a different matter and had full pressure sets and mandatory baro cell/pressure breathing training for the pilots.

[Lonewolf_50]

Germanwings crash: Evidence points to mechanical failure, say experts | News | Travel Trade Gazette (http://www.ttgdigital.com/news/germanwings-crash-evidence-points-to-mechanical-failure-say-experts/4695632.article)

What evidence is she referring to? :confused: Unless this person has access to flight recorder data and the crash site, I find this analysis premature at best ... at first blush it borders on irresponsible and unprofessional given her position.

Hunter58:
IMHO those doors have, whether aplicable in this case or not, endangered more
lives than saved.
That might be a topic worthy of a second thread. Some might be interested in how you came to that conclusion.

[Eboy]

Perhaps ACARS reported abnormal equipment events.

[abdunbar]

Btw, have we ever heard from BEA what happened to Air Asia A320?

They were part of the investigation (though not in the lead). But how can it happen that 3 months after that accident we do not know about the cause WITH all recorders orderly retrieved.

What can we expect from BEA this afternoon and in this case?

The further away in time from an event the dynamics change;

the public forgets and isn't as interested or at least the press doesn't think so and for that reason the old incident is not on the front burner with the press.

next there are many interest groups with joint and opposing interests who will lobby government bodies and try to control the narrative and news releases in their favor. These interest groups are company, manufacture, regulators, politicians, employees and employee unions. Probably others also and they all have lawyers.

Now if there is some profound discovery early on in an investigation, a discovery that points to likely further and imminent occurence of similar failures, then you will see regulative action right away. As that has not occurred in the Latest Malaysia case then it would be fair to assume that nothing profound or unusual that has not been dealt with by previous rules and notices has been found. Now is the time for the lawyers and politicians to maneuver and determine whose ox will be gored.

[Aldente]

Germanwings crash: Evidence points to mechanical failure, say experts | News | Travel Trade Gazette

"This, she said, indicated that the crew were struggling to control the pitch of the aircraft “due to a servo actuator or hydraulic failure” and was therefore unable to fly high enough to clear the mountains"

However, the theory does not explain why no distress call was made during the eight-minute descent .

Quite so......

:ugh:

[busTRE]

To those calling for auto terrain avoidance.

In the past 5 years my Airbus has 'thought' it was going to hit some granite on 3 occasions including while holding over London. If it had taken it upon itself to carry out the avoidance maneuvre on each occasion there is a significant chance I would not be here now.

More automation isn't always the answer.

[Vilters]

Some questions are posted about the crash site.

Car crashes are performed at 60 km/u, and see what remains of these steel cages.

Some time ago an institute did a car crash test at 120 km/u. The nominal max speed in Western Europe. => those results where eye openers.

Now you have an alumunum thin walled tube, smashing in a rock at a multiple of those car crash speeds.

Technical failure preventing pitch control as stated abvove?
Does that reporter even ""know"" how many ways there are to control pitch?

Windscreen crack or blowout "IS" a possibility.
With a 450 kt , -40°C windchill, storming into the cockpit?

After the initial shock, (averaging 5-10 seconds for a normal human in a relaxed state) , remember, you are just leveling off, checks done, starting to relax as this is supposed to be the "easy part".

After the intial BANG, the first pilot/human reaction is life preservation.
And it takes seconds to analyse, think, act - react.
+ Certainly shock of seeing a wounded pilot/copilot next to you.

Deathening noise, shearing -40°wind, "Where is my mask". be sure it will be NOTHING like in a simm, hell, I have to get lower.

Damm, start desend . . no time
it's over in seconds..

[Flaperon75]

...that's what you have at 38,000ft.... 12 seconds of useful consciousness.... not long!

Imagine a scenario where, say, the windscreen goes. All of the paperwork in the flight deck gets thrown into the air, several kilos of dust from every surface in the flight deck is sucked into the air also, visibility reduces. You've got 400 kts of headwind in your face. The loud roar this produces makes communication impossible. Your ears are agony. Any trapped air inside your body is agony. Maybe you've been hit by parts of windscreen blown into the flight deck and you're injured.

With this as the backdrop you have to fumble for your oxygen mask and get it on. A a previous post said..

If the masks are donned in an unpressurised aircraft at FL380 they will not provide sufficient O2 for the crew as there is insufficient partial pressure to breathe. The mask must be switched to the emergency setting (unless A320 has a different system) to provide ram air O2 to enable breathing. If this was not known or done by the crew then the mask would be of little use.

So you've donned your mask, maybe it's not set to 'emergency' setting. You cary out the initial items of the emergency descent drill which include 'pull altitude knob and turn' (set to FL70?) Remember at this stage you are not checking the value you have set it to. At a later stage in the drill you are to return to the alt knob and set FL100 or MSA (whichever higher) but before you can get to this stage your 12 seconds are up. So the aircraft continues in a controlled, thrust idle, descent, with 2 unconscious crew in the flight deck and FL70 set in the window.

At FL70 (6800 feet) the aircraft levels off and you are now below the level of the terrain. We know what happens next.

[Bleve]

Originally posted by lapp:
I have read the references and relates postings and must say that what you say is correct. Notwithstanding, it is my totally personal opinion, that setting "EMER"for mask breathing at FL 380 can't do nothing but help breathing. Would you elaborate on the possible negative consequences of doing that.

Have a careful read of my post at 25th Mar 2015, 05:10 (currently # 438) that describes exactly how a diluter/demand system works. It doesn't matter if the Demand setting is in Normal or Emergency, when you inhale you will get exactly the same pressure of gas. The only difference is when you are NOT inhaling - in Normal no gas will flow, in Emergency gas will flow (to keep the mask clear of smoke or fumes). So you are sort of half correct and fully half wrong. You are wrong by saying 'nothing but help breathing' because it provides no additional benefit - when you are breathing in you get the same amount of gas regardless of the Normal/Emergency setting. You are nearly half correct by asking about 'possible negative consequences': in a smoke/fumes incident there are none, but in a 'simple' depressurisation event the possible negative consequence is that you are unnecessarily wasting oxygen.

Are you freespeed2 posting under a different name?

[Founder]

According to Swedish Media the French Accident Investigators will have a press-conference at 16:00 Central European Time... in less than an hour from now...

[Shaggy Sheep Driver]

Concorde at 65000 was a different matter and had full pressure sets and mandatory baro cell/pressure breathing training for the pilots.

Concorde never flew above 60,000' with pax on, a rule imposed because of what would happen in the case of a depressurisation event.

[areobat]

Decompression has been ruled out by GermanWings. This leaves me completely clueless.ACARS sat data? I believe that cabin altitude is a transmitted parameter. If this stayed WNL for the last segment of the flight, then decompression could be ruled out.

[Pontius Navigator]

Explosive decompression is a near instantaneous as you will get. As suggested, on a large aircraft you would not expect explosive decompression from loss of cabin Windows etc.

Loss of cabin pressurisation could be a slower event but one presumes loss of pressure warnings would give time to react.

Between these is rapid decompression. Now there was speculation of loss of a windscreen. In the case of, poof its gone, you would have an explosive decompression. But more likely might be a rapid failure.

Say one layer cracking, then detaching, then intermediate and final layers failing in turn. At that point you might reduce cabin pressure and reduce pressure differential. The rate of failure may then increase leading to explosive decompression.

I am not suggesting this as a cause but suggesting that there are slower ways for decompression to occur.

[highflyer40]

As to the wreckage. Just look at how much was left of the aircraft that hit the twin towers, tiny pieces is about all, and that was hitting a building, granite is much stronger

[BravoDeltaVictor]

French media now report a shepard saw the aircraft flying at low altitude, turning around a hill top and then crashing another hill.


Crash dans les Alpes : "On a sûrement été les derniers à voir cet avion" (http://www.francetvinfo.fr/faits-divers/accident/crash-dans-les-alpes/crash-dans-les-alpes-on-a-surement-ete-les-derniers-a-voir-cet-avion_857879.html)


Not sure if this is a credible witness, but this would mean at least someone was still flying the plane. Makes the mystery of why there was no comms or even changing squawk bigger.

[Lord Spandex Masher]

Post Helios, there are SOPs for crew to enter the Flt Deck. I cannot envisage any Flt Crew remaining in the toilet during a gentle extended descent?

Not at every airline there isn't.

[ia1166]

It's made it to the papers now, and it's is speculation at best, a poor theory at worst.

[Lonewolf_50]

Decompression and pilot capacitation would result in the aircraft continuing to destination. Why is everyone fixated on this?
Because (see numerous posts in the last few pages) there may be enough time to get the first few steps of the emergency procedure drill completed before losing consciousness. A well trained crew will revert to training in an emergency, points on startle factor above considered.

[Denti]

Sorry if a lame question, but I have been trying to find a definitive copy of the European equivalent of FAR 121 in the European regulations and have been unable to do so.

Took me 3 minutes to find the FAR 121 bits, but unable still to find the EASA(?) equivalent. The old JAR was almost a carbon copy of FAR.

The JARs were in many parts similar, but far from being a carbon copy of the FARs.
´
Anyway, check out CAT.IDE.A.235 Supplemental oxygen — pressurised aeroplanes.

The regulation can be found on the EASA page of course.

[WingNut60]

Has anyone considered what the dynamic pressure might be like in the cockpit with the door closed and one or more windshield panels missing.


Air flow past the missing panel might result in a lowering of pressure inside the cockpit (ref venturi / Bernoulli) OR there could be some ram effect.


I can well imagine that the environment would be extremely turbulent and debilitating (deadly) but not so sure that you'd be in a low pressure environment or that O2 partial pressure would be a problem in itself.

[Flaperon75]

Decompression and pilot capacitation would result in the aircraft continuing to destination.

Hmm... not true. Airbus doesn't automatically descend at FMCG calculated 'Top of Descent' point - it requires pilots to descend aircraft.

Plus see my post above. In that scenario the descent is initiated and follows lateral flight path but in a descent.

[ia1166]

The first few steps of the excess cabin altitude drill does not include

Autopilot.....disconnect.

It is

Oxy mask....don

Comm...establish which in the sim includes a mayday call requesting descent.

You are barking up the wrong tree.

[ia1166]

I did not say it would descend. I said it would continue to destination.

I only have 13000 hours on the 320.

[henra]

Air France and air asia. Neither crew got a mayday out. Both lost control of the aircraft.


Here, we have an IAS of around 340kts and a straight flightpath for 8 minutes. This doesn't scream loss of (aerodynamic) control...

[Sanbaronto]

Dutch media report FDR has been found but very damaged. Memory card is missing.

[procede]

Has anyone considered what the dynamic pressure might be like in the cockpit with the door closed and one or more windshield panels missing.


Air flow past the missing panel might result in a lowering of pressure inside the cockpit (ref venturi / Bernoulli) OR there could be some ram effect.


I can well imagine that the environment would be extremely turbulent and debilitating (deadly) but not so sure that you'd be in a low pressure environment or that O2 partial pressure would be a problem in itself.

According to ISA static pressure is .228 Bar. Density 0.35 kg/m3.
Speed =400 kts = +/- 200m/s (ignoring wind speed)
Dynamic pressure at stagnation point is thus 0.5*0.35*200^2=0.07 Bar, thus about a third outside pressure making the total pressure in the cockpit .3 Bar, equivalent to 30k altitude (at best).

The static pressure with a side window would be the static outside air pressure, as the dynamic pressure is caused by the airplane speed, not a narrowing of a channel.

Another issue would be the deafening noise inside the cockpit flying at 400 knots TAS with an open window...

[CDG1]

The French Ministry of the Interior have published official high resolution pictures of the crash site.

Moyens mobilisés sur la zone du crash de l'A320 de la Compagnie Germanwings
Ministère de l'Intérieur - SIrpa Gendarmerie - F.Balsamo

https://www.flickr.com/photos/ministere_interieur/16924817002/in/photostream/

(click on the pictures for high resolution)

[deefer dog]

The first few steps of the excess cabin altitude drill does not include

Autopilot.....disconnect.

It is

Oxy mask....don

Comm...establish which in the sim includes a mayday call requesting descent.

You are barking up the wrong tree.

Establish comms does not mean the inclusion of a mayday call requesting descent.

[skyhighfallguy]

I've just seen a picture of the CVR and it is messed up.

BUT when you see it, the rectangular part is messed up, but the round part, which is the part with the memory modules, looks pretty good.

[wiljaxon]

I used to be a CAA licensed engineer - a failure of the the forward pressure bulkhead could be the cause. An inability to close the nose gear doors may have been a symptom. There was a proposed airworthiness directive, PAD No.: 14-110, I quote:

"During the A320 fatigue test campaign for Extended Service Goal (ESG), it was determined that fatigue damage could develop on the forward pressure
bulkhead at Frame (FR) 35 on Left Hand (LH) side and Right Hand (RH) side.

This condition, if not detected and corrected, could affect the structural integrity of the aeroplane.

To address this potential unsafe condition, a reinforcement modification was
developed, which has been published through Airbus Service Bulletin (SB)
A320-53-1268 for in-service application to allow aeroplanes to operate up to the new ESG limit.

For the reasons describe above, this AD requires reinforcement of the centre
fuselage forward pressure bulkhead at FR35."

Maybe this AD was carried out, but incorrectly?

[Flaperon75]

My point is that in a decompression, you don your mask and establish comm.

The pf initiates a descent to 100 or msa, and the PNF makes a mayday call.

Incorrect.

Initial drill is to initiate descent.

At a later stage in the drill you set FL100 or MSA.

Big difference from what you said and may be very important.

[MichaelKPIT]

"But the search for clues about what caused the crash was dealt a setback Wednesday afternoon, as investigators said they had so far been unable to retrieve any data from the plane’s cockpit voice recorder. The inquiry has been hampered further, an official said, by the discovery that the second black box, which was found on Wednesday, was severely damaged, and its memory card was dislodged and missing."

[ia1166]

The initial drill is to don your oxygen mask, make a pa to the cabin and initiate a descent.

The PNF should don oxy mask and make a call to atc.

What pilot would initiate a descent before donning his mask

It's not the correct procedure at all.

[grimmrad]

Satellite link and frequent data upload anyone...?

[Aeromar27]

Incorrect.

Initial drill is to initiate descent.

At a later stage in the drill you set FL100 or MSA.

Big difference from what you said and may be very important.

If related to this particular accident we still don't know, but, wouldn't it be good to limit the range at which the altitude selector changes 1000ft per click? Or at least make it stop at a certain altitude selection requiring further input to go below that limit.

[surfinJ]

Back in the air force I underwent hypoxia training, mostly to recognize symptoms, at a slow depressurization rate. I remember it being not at all unpleasant. You were barely conscious of the changes acurring to your mental state.

I recently experienced a rapid decompression to 12900' cabin altitude. A cabin pressure controller failed, the backup switching circuit failed, and as a surprise the fail safe mode drove the outflow valves full open. Timely actions of my FO regaining manual control over the outflow caves saved us from an emergency descent.

What I didn't expect was how the rapid depressurization felt. You felt very ill throughout your whole body. I can only imagine a catastrophic pressurization loss would combine the two, leaving very limited functioning ability.

The BA windscreen event happened at 17000', closer to what I experienced, not nearly what FL380 would produce.

[ionagh]

Grimmrad

Since MH370 the ITU-R has set up a working group specifically to investigate and propose suitable technology for real-time tracking/monitoring of aircraft.
May take a few years but it will come.

[GearDown&Locked]

NY Times said what? :rolleyes:

the pics (from BEA!!) of the CVR show the memory cards cilinder quite intact and still attached to its base. Unless the memory cards can "evaporate" :ugh:

[ia1166]

My point about the autopilot is that the aircraft should have levelled off at the fcu selected altitude. The PF should have whizzed in a lower altitude, and then refined it second time around. Either way it should have been set at something above 100 or refined to 100 or msa. If the pilots were incapacitated then the ap would have levelled off at the fcu alt.

Who knows anyway, it's all speculation and the conviction here for this theory is unfounded.

There are many other possibilities. Some more likely than this one.

[SAMPUBLIUS]

md11 said... They are fitted from the outside, same as the B747, B757 and B767.

From recollection- B767 cockpit skull cap ( upper half of cockpit-windscreen assembly ) used Titanium surround. This was the result of tests with chicken cannon which fired a large ( dead) chicken carcass at windshield and windshield crown section. On the early 767, major hydraulic systems/valves came together in the crown and loss of those would be a disaster.


And from memory - it is NOT impossible that some sort of ' bird' strike' at that altitude may have happened.

[skyhighfallguy]

geardown:

the picture is of the CVR, which I commented upon.

the NY TIMES is talking about the recovery of the FDR, which seems to have more damage to the round part containing the memory modules.

FDR is not CVR, capish?

[skippybangkok]

Re: the discussions on automatic terrain avoidance, I find it incredible that an Airbus which can automatically ensure it is not flown outside of it's flight can be flow into terrain

It's call a landing... Typically executed on a runway

[DIBO]

BEA Press Conf about to start (4pm Paris time)
https://www.youtube.com/watch?v=yAQOSveCJqc

[MichaelKPIT]

Well the pics are showing the CVR. What NYT is saying is that they found the FDR but it's card is dislodged and missing.

[wiggy]

Gear/Michael

Well there now doesn't seem to even be agreement as to the state of the black boxes, so what hope for coherence on anything else....this from AFP this afternoon..(1425 European time):

"A second so-called black box, in this case recording flight data, has yet to be found on the mountain in the French Alps where the Airbus A320 went down Tuesday.

Photos issued by the BEA crash investigation office showed the black box -- in fact coloured orange -- in a badly mangled state, its metal casing twisted and ripped by the force of the crash.

Officials acknowledge it is badly damaged but say they still expect to retrieve some data from it, although it may take some time."

I must admit having seen a fair bit of French TV coverage over the last 24 hours, some good, some bad, I'm inclined to agree with the French take on what's been found and the state it's in ...and I suspect in any case we really can now consign this mornings story about investigators hearing the windscreen breaking to the bin.

Flash - French air disaster black box 'damaged' - France 24 (http://www.france24.com/en/20150325-french-air-disaster-black-box-damaged/)

[Lonewolf_50]

ia1166
Am familiar with this AD (http://www.caa.co.uk/docs/33/20121204EASAAD20120258E.pdf)and the more recent issues related to OEB 48.

Since a crew recently recovered in about 4000 feet from that malfunction, and this A320 accident had an altitude differential of about 30,000 feet between ToC and ground impact, and the issues with the AoA malfunction have gotten wide circulation, an initial estimate of the crew being able to handle that AoA malfunction seems reasonable.
Granted, ruling that out is probably premature (particularly if other malfunctions were present) but it doesn't seem to fit very well with what is known in the public domain. Your caution on over-speculation is accepted. :ok:

[skyhighfallguy]

Because we practice the proper way to handle a loss of cabin pressure, and we have to show examiners in the simulator, over and over, for years, we would LIKELY do it the right way in an emergency because it is now the easiest way to deal with things.

THE WEAK point is that the oxygen system is not duplicated at the source of the oxygen. We have two engines on the plane, but only ONE cylinder of oxygen. (cockpit).

IF the oxygen masks dropped in the main cabin, flight attendants with "WALK AROUND BOTTLES" would eventually check on the pilots if possible. PA announcements from the cockpit would preclude the need to check on them.

IT IS Likely the passenger oxygen system was a design with oxygen generators, BUT SINCE I AM NOT a pilot for GERMANWINGS, I ask this question:


IS THE MAIN CABIN/PASSENGER oxygen system a cylinder or individual oxygen generators?

I hope this is a reasonable question and not flamed like what happened to old boeing driver's reasonable question.

[Sillert,V.I.]

Anyone considering windscreen failure/rapid decompression would do well to read the AAIB report for the 1-11 incident (http://www.aaib.gov.uk/cms_resources.cfm?file=/1-1992%20G-BJRT[2].pdf) to G-BJRT.

That happened as the A/C was passing FL170; imagining the same scenario at FL380 is thought provoking.

In that incident, "the flight deck door had been blown onto the flight deck where it lay across the radio and navigation console".

Would a current-day reinforced door remain in place after a rapid cockpit decompression at FL380?

[Bleve]

Pontius Navigator
Explosive decompression is a near instantaneous as you will get. As suggested, on a large aircraft you would not expect explosive decompression from loss of cabin Windows etc.

The 2008 Qantas event is informative. When cruising at 29 000' (cabin altitude 3 700') an oxygen bottle exploded creating a 3 square metre hole in the fuselage. One second later the A/P disconnected and the aircraft pitched nose UP. Three seconds later the cabin altitude reached 10 000'. Pilots put on oxy masks and established communications with each other. At 22 seconds descent was initiated (thrust to idle/ speed brakes extended). At approx 40 seconds the uncommanded climb was reversed and and the descent established, maximum cabin of 25 900' occurred at about this time. The mean rate of descent was about 3 000 fpm and the cabin altitude was about about 3000' below the aircraft's altitude during the descent.

The key points are that at 29 000' and with a 3 sq m hole, cabin altitude reached 10 000' within 3" and 26 000' within 40". With idle thrust, speed brakes extended snd IAS at the cruise IAS, descent rate was ~ 3 000 fpm.

[Evanelpus]

This is my first post on here. As a non-professional pilot (PPL in training) but a long time follower of this forum, it is most tiresome to read constant "stop speculating" posts.

OK, we all want to know the truth about what has happened, but this thread is now 30-odd pages long, half of which is speculation and half of which is people moaning about the speculation.

Every thread about air accidents here is full of conjecture. That's the nature of a forum - people discuss their different opinions. Constantly bleating about this adds nothing, but the speculation does at least stimulate debate. But surely it's time to recognise that this is a forum and everyone is entitled to an opinion. Moaning about it won't change it. If you don't agree with what someone says, offer an evidence-based rebuttal which can further inform the debate. Throwing the teddies out of the pram hardly helps things does it, and history proves that you're on a hiding to nothing anyway!

Can you imagine what these forums would look like if it were entirely speculation and debate-free?

Post 1: There's been a crash
Post 2: (8 months later) AAIB report
End of thread.

Some posts are stupid, I accept that, but why oh why do people need to take such issue with people offering a potential cause or asking about the viability of certain events occurring?

Some people know more than others, but seriously - join in what is, on the whole, a constructive debate. If you don't want to discuss the possibilities, don't join in at all.

As someone who takes an interest in air safety and aviation incidents, I find this forum most informative and it allows me to consider privately, what my views about a potential cause of this tragedy might be. I won't post that, because I'm not well-informed enough to know the truth, but I read all the posts with an open mind and with interest.

I would also like to thank all of you guys who do have first-hand knowledge of these aircraft, flight procedures and protocols, systems and other aspects who make these threads very interesting.

And for those journalists who think that this forum is full of facts ready to be spewed verbatim onto the TV screen, please think again. This is a rumour network after all

Quite a first post there Morten. For a lot of us here (who seem to have been here since Pontious was a pilot) what you said isn't new. You won't stop what you've written about and I, for one, am tired of 'newbies' first post telling us what we should and shouldn't be writing about. Lecture over.

found the FDR but it's card is dislodged and missing.

It's either dislodged or it's missing, it can't be both schurley Mish Moneypenny.

[sp3ctre]

Quite a first post there Morten. For a lot of us here (who seem to have been here since Pontious was a pilot) what you said isn't new. You won't stop what you've written about and I, for one, am tired of 'newbies' first post telling us what we should and shouldn't be writing about. Lecture over.


You must admit a lot of people on here seem borderline aggressive in response to some questions. Sure, some pilots on here have 200 years of flying experience, but they could at least maintain a level of politeness when addressing people's questions/comments, however stupid they maybe.

[A310bcal]

"One thing that may be important: with both this incident and MH370 one of the pilots was relatively inexperienced. The emergency may have occurred when the more experienced pilot was in the bathroom for instance. When was the last time a serious incident occurred with two very experienced pilots in the cockpit? (without being successfully resolved, I mean)"

Has anyone yet seen/heard what the F/O's credentials are ? The Captain has massive history/experience, but what of his co-pilot? It is supposed ,after all , to be a crew. But I'd be interested in knowing a bit more about the guys background , nationality , etc.

[Officer Kite]

To whoever came to their own conclusion that it was a windscreen crack that caused the accident ...

Did Germanwings 4U 9525 plane windscreen CRACK before French Alps crash? | Daily Mail Online (http://www.dailymail.co.uk/news/article-3010610/French-alps-crash-French-alps-Germanwings-plane-crash-Lufthansa-GWI9525-4U9525-Airbus-A320-Barcelonnette-Alpes-Hautes-Digne-Les-Bains.html)

I'm amazed at how people can be so informed about an event while watching it all from their armchair.

If ever I needed a reason not to read the Daily Mail.

They even provide a link to this site as ! :ugh:

[DIBO]

BEA Press Conf about to start (4pm Paris time)
but first the politicians....
https://www.youtube.com/watch?v=1ZYZG8Yybgw

[henra]

There are many other possibilities. Some more likely than this one.

If you are referring to OEB48: Rather unlikely.
For multiple reasons.
Besides what @Lonewolf mentioned:
1. They were in cruise. Freezing would have occcured earlier in all likelyhood.
2. This problem is mostly relevant in climb. In climb Mach number will increase with altitude, thus critical AoA will reduce. At the same time the AoA will increase with decreasing CAS. Therefore with a probe frozen at a constant angle the system will try to correct for increasing Mach. In cruise Mach won't change significantly and Alpha_prot won't usually be reached (especially since there was no significant weather reportde in the area). Only at Alpha_prot and at the same time significantly increasing Mach number the chain described in the Bulletin will be triggered.
Edit: So in summary for this to apply here you need: No freezing in climb, then freezing in cruise, flying at Alpha_Prot, Mach number increasing. And all at the same time and while flying at ~280kts (Alpha_prot @1g should kick in around 170 - 180 kts, so you would have a margin of about 2,4g).
/Edit
3. They had 8 minutes time to:
pull two CB's or
change heading towards lower terrain or
communicate their problems or
select 7700.
Nothing of those happened.
Not saying it is necessarily decompression but Occam's razor has a hard time with the scenario described in the OEB.

[oceancrosser]

The 2008 Qantas event is informative. When cruising at 29 000' (cabin altitude 3 700') an oxygen bottle exploded creating a 3 square metre hole in the fuselage. One second later the A/P disconnected and the aircraft pitched nose UP. Three seconds later the cabin altitude reached 10 000'. Pilots put on oxy masks and established communications with each other. At 22 seconds descent was initiated (thrust to idle/ speed brakes extended). At approx 40 seconds the uncommanded climb was reversed and and the descent established, maximum cabin of 25 900' occurred at about this time. The mean rate of descent was about 3 000 fpm and the cabin altitude was about about 3000' below the aircraft's altitude during the descent.

The key points are that at 29 000' and with a 3 sq m hole, cabin altitude reached 10 000' within 3" and 26 000' within 40". With idle thrust, speed brakes extended snd IAS at the cruise IAS, descent rate was ~ 3 000 fpm.

I could see an event where the crew oxygen bottle blew out leading to something like this. Explosive decompression, pilots without oxygen. Not an Airbus pilot, where is the oxy bottle on the A320?

[Fafnir_stolberg]

The toxicity of oxygen is a problem when (mostly ill) lungs are exposed to high concentrations of oxygen> 50% for a long time (days). Oxygen radicals are supposed to do structural damage to the alveolar membranes. Another problem of breathing of 100 % oxygen are atelectasis (collapsed areas of the lung due to complete resorption of oxygen in absence of nitrogen). A continous flow, providing an positive endspiratory pressure, solves the problem.Conclusion: If an pilot is alone in the cockpit in dangerous hights, he would be wise to wear a mask, breathing 40 % of oxygen, thus changing his hypoxia tolerance from seconds to minutes. Hygenical problems shouldn`t be a problem in the times of single use devices. By the way- every fire brigade can show you how to keep reusable masks hygienically clean.

[SAMPUBLIUS]

Tigger said Between 10,000 and 15,000 ft the ability to perform skilled tasks such as aircraft control and navigation are impaired

I've been at 14K feet on Mount Rainier. The above description is accurate, especially when happening almost instantaneously. While climbing from 10,000 feet for 6 to 8 hours allows one to sort of acclimate- most first timers( like myself years ago ) start to have a hard time doing all but the most simple tasks-or concentrating. While one would think you would be gasping for breath above 12K or so, you do NOT notice that effect other than the exertion issue which **seems** to be moderate. IMHO- those who think they can remember a multi step procedure under more severe cases ( above 25 to 30 K feet for example ) are simply kidding themselves. Any such response will probably be from " memory' - muscle memory- or similar. Which requires practice, practice, practice. I'm sure a condensation ( moisture smoke) filled cockpit does not help ..

[pavlik1]

to me the container with the memory is intact.
http://stat.ks.kidsklik.com/statics/files/2012/05/13372140021941522945_300x279.54545454545.jpghttp://avherald.com/img/germanwings_a320_d-aipx_barcelonnette_150324_5.jpg

[Mozella]

Agreed. Over the ocean auto descent after pressurisation failure might be useful but in busy European & US skies a plummet without some sort of ATC clearance could lead to more serious consequences. A mid-air would clearly be more hazardous than temporary hypoxia for some passengers.

I'll have to disagree. A study done some years ago concluded that, strictly from a statistical point of view, mid-air collisions would occur at a lower rate if pilots flew at random altitudes and directions completely uncontrolled. In other words, the sky is a big place.

Yes, a midair will ruin your day, no argument there. But if you turn off course, it's so freakishly unlikely that it's hardly worth considering. Can anyone reference a single midair resulting from an airline pilot doing what he felt was necessary during a serious emergency?

In an airliner suffering decompression, if you do everything correctly, the pilots are still in serious danger as long as they are at an altitude above which they can operate without supplemental oxygen. If it were me, I'd be on my way to a lower altitude immediately.

Waiting for ATC clearance during ANY very serious emergency was NOT in my bag of tricks back when I was flying over the North Atlantic and Europe. I suspect more people have died by turning control of their aircraft over to ATC than have died by doing what was necessary during a genuine emergency and then telling ATC about it later.

[pbeardmore]

NYT

Speaking on the French radio station RTL, Interior Minister Bernard Cazeneuve said on Wednesday that terrorism was “not a privileged hypothesis at the moment,” but that no theories had been definitively excluded. Mr. Cazeneuve said the size of the area over which debris was scattered suggested that the aircraft had not exploded in the air but rather had disintegrated on impact.

He said that the plane’s cockpit voice recorder, the first black box that was recovered, was damaged, but that investigators expected to be able to recover the conversations stored on its memory chip.

But as of early afternoon, a senior official involved in the investigation said analysts had so far been unsuccessful in retrieving any information from the cockpit voice recorder.

[MrSnuggles]

After looking on a few photos of the crash site, I believe there were some kind of post impact fire. The hillsides are blackened and in one picture you can see a small spruce all black. It seems the soil layer was very thin and it is unlikely that the aircraft would have made a large crater. A dent would be more in line with what the photos tell.

My sympathies goes out for all that lost dear ones and for the rescue crew. I can't imagine the awful awful task they have, picking pieces of humans from the ground. If anybody knows how to help the helpers, I wouldn't think twice to volunteer!

[Cagedh]

Live speech from Hollande, Merkel and Rajoy.
https://www.youtube.com/watch?v=1ZYZG8Yybgw

[carma1958]

What pictures are these on CNN of the CVR and FDR??? These units have old corrosion on them. In my opinion these 2 units have been damaged quite a while ago.

[MrSnuggles]

Here is a good picture of the charred mountainside. If you look closely you can see burnt trees. The unharmed terrain is beige-brown with the affected parts being black.

https://farm8.staticflickr.com/7288/16718867657_db3d6fdaba_c.jpg

Picture taken from https://www.flickr.com/photos/ministere_interieur/16718867657/in/album-72157649223170784/

[elkinsoto]

Hollande said only one "black box" was found...

[ATSMAN]

I was an ATC instructor, with tuition including ATC handling of all types of aircraft emergencies. In the event of explosive decompression we'd expect the pilot to turn off track, initiate a descent and only then..set the emergency sqk and communicate. With TCAS, turning off track may not be immediately necessary!

[ZeBedie]

Is there any data from ACARS?

[Cagedh]

quote from press conference: useful information gas been retrieved from CVR

[RHRHRTTG]

Food for thought, the "bulkhead" separating the cockpit from the rest of the cabin is obviously not designed as part of the pressure cell. If the door has been beefed up sufficiently to prevent an aggressor entering the cockpit and should it remain (or try to remain) in place during a rapid decompression via the cockpit area then the parts that will not remain in place will be the toilet and galley backwalls. Seeing that the O² masks are situated slightly to the rear of the crew and are accessable via a small cover door that has to be raised in order to gain access which could be prevented by debris from the backwall failure. If the main cabin evacuates via the cockpit there will be massive movement in this area. Lets hope the CVR and FDR throw some light on this tragedy

[wiggy]

...and one of the main priorities now is finding the FDR......

[auldlassie]

From the Guardian - Recordings successfully extracted from cockpit voice recorders

As the press conference ends, Reuters reports that the French air accident investigator, BEA, says it has successfully extracted recordings from the cockpit voice recorder of the downed Germanwings Jet, contradicting the New York Times report from earlier.

And for elkinsoto - At the briefing, the Hollande said that the “envelope of the second black box has been found, unfortunately not the black box itself”. He said the search goes on for that.

The BEA press conference is about to start.

[Velhurstairport]

The Les Echos live app won't let me copy and paste but is reporting that the envelope of the FDR has been recovered but not the actual FDR.

Also that the CVR has been exploited.

[jkstark]

From avherald


According to Finnish CAA in Finnish newpaper Helsingin Sanomat, the CVR has revealed crew was unconscious in the start of descent.So looks like Helios 2.


Actually, the article states that they were *probably* unconscious - essentially they are speculating just as much as everybody else at this time. They do mention that some data has been recovered from the FDR, and state that the assumption is that the crew was unconscious based on the lack of communication as evidenced by the CVR. They go on to speculate that the unconsciousness may have been due to hypoxia, and then on to how pressurization may have failed - ie. a puncture or a failure of the pressurization system.

[Checkboard]

No!

Not if the pressure failure was forward of the door, in that case the cockpit door controller unit unlocks the door, and the door opens (towards the cockpit) under differential pressure.

[threep]

At the briefing, the Hollande said that the “envelope of the second black box has been found, unfortunately not the black box itself”. He said the search goes on for that.

Although its difficult terrain, its not unimaginable that a square metre by square metre search will find the missing memory unit from the flight data recorder, even if it takes weeks or months.

[Speed of Sound]

BEA spokesman has just categorically confirmed that they have NOT found the FDR.

[Superpilot]

I, like most pilots have not experienced a rapid decompression but I have flown with a captain who has. The experience he shared was most enlightening. When it happens you literally feel like the back of the aircraft has exploded. Your tongue is swallowed by your throat in a second, your ears begin to hurt and teeth become a hundred times more sensitive. If you already have an ear infection or a bad filling, you're likely to pass out as a result of the instant pain. None of these can be simulated in a sim or be trained for. On top of that, the cockpit fills with a cold mist that freezes the skin. All of these aspects make it incredibly difficult to recognise and reach out for the oxygen mask and autopilot controls. Stressing or moving about rapidly to find/don the oxygen mask chews into the time of useful conciousness.

I also agree that the flight path and steady descent indicates an informed decision to initiate an emergency descent. Done correctly, the target altitude would have been set to FL100 as a minimum. However looking even 30cm ahead can be challenging and that has the potential to result in the pilot setting the wrong target altitude.

[JamesT73J]

Was there a fire on impact of germanwings ?


I think the blackened mountainside is just the rock colour - reason being the painted parts of the wreckage that you can see in the photos don't appear to have been sooted or charred.

[Pontius Navigator]

The 2008 Qantas event is informative. When cruising at 29 000' (cabin altitude 3 700') an oxygen bottle exploded creating a 3 square metre hole in the fuselage. One second later the A/P disconnected and the aircraft pitched nose UP. Three seconds later the cabin altitude reached 10 000'. Pilots put on oxy masks and established communications with each other. At 22 seconds descent was initiated (thrust to idle/ speed brakes extended). At approx 40 seconds the uncommanded climb was reversed and and the descent established, maximum cabin of 25 900' occurred at about this time. The mean rate of descent was about 3 000 fpm and the cabin altitude was about about 3000' below the aircraft's altitude during the descent.

The key points are that at 29 000' and with a 3 sq m hole, cabin altitude reached 10 000' within 3" and 26 000' within 40". With idle thrust, speed brakes extended snd IAS at the cruise IAS, descent rate was ~ 3 000 fpm.

I was cite that as rapid. Loss of the windscreen may well have become explosive after initial slower decompression.

[Speed of Sound]

BEA spokesman getting very jittery in response to questions about the CVR.

He has admitted that it has useful information (suggesting it has been listened to) but won't say what was heard!

[Curious Mind]

BEA spokesman getting very jittery in response to questions about the CVR.

I would not say "jittery", but "prudent" and reluctant to give information that are not confirmed (he said he did not listened to that recording) and could be misinterpreted.

[mosteo]

BEA spokesperson just said that he has no info on the availability of ACARS in this flight

[NigelOnDraft]

I may have missed it but has anyone mentioned ACARS data transmission? If the A/C was equipped and if it was used? Bear in mind ACARS overland is typically crude VHF unencrypted data transfer, which spotters / ham radio types can receive AFAIK? So if anything dramatic was sent, somebody might have said?

I would think the BEA will prioritise what they do have in conventional data sources (CVR, FDR, Mode S, ADS-B, ATC etc.). AF447 resorted to ACARS due to a high level of integration, and absence of other sources...

[Cows getting bigger]

There can only be three reasons why pilots would not communicate with ATC under such circumstances (an unplanned rapid descent):

a. They are incapacitated - 30 or so pages discussing hypoxia.
b. They are unable due to equipment failure - not much discussion.
c. They (plural or singular) chose not to communicate - no discussion at all.

I'm not pointing in any particular direction other than highlighting the fact that we, the Great pprune Collective, seem to have decided to focus on only one of the above.

[geneman]

Two recent quotes from Remi Jouty of the BEA (accident investigation team) at the news conference.


Jouty: Sound recorder was found on site around 17:00 local time on Tuesday and was quickly sent to BEA, arriving at 09:45 on Wednesday

Jouty: We have been able to extract a usable audio file from the sound recorder.

[costalpilot]

giving indications that the ac flew till the end

no in air explosion indicated

audio file usable

has no info on whats on it

they haven't got or tried to get any info from the airline involved...yet

(the cnn feed translator is very good)

[betterfromabove]

As a geologist who's done fieldwork in this area, agree with JamesT73 that these look like classic organic-rich (i.e. intensely black) shales to me and hence is their naturally colour. The more resistant, thin, lighter coloured rocks (seemingly uncharred) are white-yellow sandstone layers. Both formed in a deep ocean, but now find themselves thrust several thousand metres into mountains. When thick, these sandstone layers will make up the base of the hill and the higher summits behind.

The damage of this impact is truly phenomenal.

[fireflybob]

Agreed. Over the ocean auto descent after pressurisation failure might be useful but in busy European & US skies a plummet without some sort of ATC clearance could lead to more serious consequences. A mid-air would clearly be more hazardous than temporary hypoxia for some passengers.

In the event of an explosive and sudden loss of pressure sheer self survival says "Go down!" - I can assure you that no pilot in the world would be messing about asking for a clearance to do so.

That does not mean that, if possible, once the descent has been started and immediate actions complete you wouldn't send a MAYDAY and/or select 7700 when you can.

[MrSnuggles]

A seemingly knowing reporter with grey hair and suit asked if there were any sounds on the CVR during the time of the descent. The BEA spokesman did not answer that and/or he said something I didn't hear properly. Does anyone know of what I am talking and if so, did you happen to hear Mr BEA's answer?

The press conference is over. It was mostly uneducated questions about how a crash investigation is conducted, if there had been terrorist threats or bombs, but this gentleman in grey hair seemed to be in the know. Maybe a reporter for an aviation journal?

[atakacs]

Well just watched the press conference and not much news: they have the cvr but would not talk about its content, categorically refuted that anything was found about the FDR, no ACARS one way or another. I guess still very early in the investigation

[oldchina]

Mr BEA didn't say when on the recording the sounds (at one point he did say 'voices') were heard. So he didn't say anything about noises during the descent.
And they are still searching for the FDR. So Pres Hollande's comments were BS.

[wiggy]

His general answer (in both French and English) to all questions about the CVR was that whilst there whilst an audio file had been found it was going to be some time before the data had been fully extracted/analysed and so he was not willing to speculate on it's contents.

His comments about the FDR are consistent with all other credible local reports - it (or at least the important bit) hasn't been found yet.

[Discorde]

Agreed. Over the ocean auto descent after pressurisation failure might be useful but in busy European & US skies a plummet without some sort of ATC clearance could lead to more serious consequences. A mid-air would clearly be more hazardous than temporary hypoxia for some passengers.

I'll have to disagree. A study done some years ago concluded that, strictly from a statistical point of view, mid-air collisions would occur at a lower rate if pilots flew at random altitudes and directions completely uncontrolled. In other words, the sky is a big place.

Yes, a midair will ruin your day, no argument there. But if you turn off course, it's so freakishly unlikely that it's hardly worth considering. Can anyone reference a single midair resulting from an airline pilot doing what he felt was necessary during a serious emergency?

In an airliner suffering decompression, if you do everything correctly, the pilots are still in serious danger as long as they are at an altitude above which they can operate without supplemental oxygen. If it were me, I'd be on my way to a lower altitude immediately.

Waiting for ATC clearance during ANY very serious emergency was NOT in my bag of tricks back when I was flying over the North Atlantic and Europe. I suspect more people have died by turning control of their aircraft over to ATC than have died by doing what was necessary during a genuine emergency and then telling ATC about it later.


It's a judgement call, Mozella. Statistics might not be on your side if you're dropping at max rate through, say, the Washington-NY-Boston area. Your TCAS advisories will be inappropriate and you will probably trigger multiple TAs and RAs on other aircraft, which could be highly disruptive (or worse).

[mosteo]

My understanding of the many replies on the CVR contents is that they had retrieved an audio file short ago, they had corroborated that things could be heard so it is usable, and that it belongs to the flight in question, but any deeper analysis is ongoing so he couldn't comment yet on whose voices are there, at which phase of the flight correspond, etc.

But yes, at some point he said there were voices on record.

[strake]

This is the best translation of the exact statement I can offer:
'We have not been able to analyze everything the pilots said after recovering the voice recorder of the crashed Germanwings plane."

We should be able to analyze and time-stamp everything recorded in the cockpit, but it may take a couple of days.

This is what Rémi Jouty, Director BEA (Bureau d'Enquêtes et d'Analyses pour la sécurité de l'aviation civile) explained today.

He did not confirm to have located the second part of the black box containing all technical data.

He had no reason why the plane started a decent and crashed with full speed in the French mountain region. French civil aviation professionals tried to contact the pilots after they noticed the unexpected decent without success.

When asked if they were be able to recognize the voice of pilots after the decent started, he refused to respond.

The speed of descent was about 3,500ft per minute, he says. There is a question about rumours of lithium in the cargo. Jouty says such questions have to be investigated.

When asked about a possible a terror attack, he also refused to respond.

[BigFrank]

I claim to accept the need for extreme prudence by the head of such an organisation in such circumstances as these.

I was however surprised that:

i) He said that he hadn't listened to the cockpit recording at all himself almost 8 hrs after it arrived on site.

ii) He refused to say if the voices were speaking in English or German

iii) He intimated that his organisation had not yet received a copy of the cargo manifest (in response to a question concerning the presence there of lithium batteries.)

[INeedTheFull90]

Stupid? Fair enough. Maybe my post was. However just watch. As the post goes on and more 'news' articals are published the theories will get more and more sensational.

A few words from the BEA could have kept some sort of restraint by the press and maybe go a ways toward reassuring the thousands who work on the 'Bus and the millions who travel on them. That is all and I make no apology whatsoever.

If you're going to have a press conference or a news conference then have something to tell. Don't regurgeteate facts already printed 24 hours ago by germanwings with a couple of extra bits of information. Give us something meaningful. In a world where people want to know EVERYTHING and know it NOW, people will just make things up to fill in the blanks.

[grumpyoldgeek]

With the talk of finding the FDR but no memory card, is it possible that they found the QAR, less it's memory card and mistaken it for the FDR?

[Speed of Sound]

But yes, at some point he said there were voices on record.

He actually said 'sounds and voices' which is no surprise.

His reason for giving no further information was that they were still syncing the recording to the flight in question.

[espike007]

Of course you can simulate explosive decompression. Every military pilot has to go through it. I went through the altitude chamber several times during my career in the Army, including explosive decompression. Yes, it's disorienting. Yes, it makes the air in your lungs expand and you cannot speak, but all of the symptoms dissipate after a few moments and you are free to put on your oxygen mask and then fly the aircraft. That cockpit crew should have had quick-don mask at the ready. Something else happened to this crew.

[SLFplatine]

We have not been able to analyze everything the pilots said after recovering the voice recorder of the crashed Germanwings plane."

We should be able to analyze and time-stamp everything recorded in the cockpit, but it may take a couple of days.

Which I would read as the pilot's voices are on the recording however, as at what point in the flight these voice recordings occurred has not been determined. Just my opinion mind you.

[ZeBedie]

is it possible that they found the QAR,

QAR is unlikely to have survived.

[Ian W]

From an anonymous comment on avherald:

Quote:
CVR data has been read. It seems structural failure (windshield? not determined yet)..It was quick... sound of cracks,but crew initiated emergency descent by autopilot and then they weren't heard anymore. Autopilot was on during whole descent, but disconnected automatically shortly before impact when GPWS alerts appeared.



Here we go again - sets of 'experts' listening to noises and trying to ascertain what went wrong and who did what. All the potential evidence was destroyed by a 375Kt collision with a rock face.

A workhorse airliner could have a fault that has demonstrably incapacitated a crew and led to the loss of life of all on board, yet because management pilot relations are so untrusting there is no simple video recording to show what went wrong.
So let's hope those SME's can identify what the failure was from the noise. Or all the A-319 - 321 series, of that vintage at least, may be flying with a problem.

[threep]

Surely if anything was heard they could have briefly summarised it. I appreciate they need to be meticulous. However the CVR has been at the BEA for several hours now. Chance for the last ten minutes of the flight to be listened to many times over. They MUST know something. This lack of information will just cause people to read between the lines and again as night falls on now day 2, with no more REAL information, speculation will become frenzied and tomorrow's newspapers (especially the vile ones we have here in the UK) will be full on sensationalist speculation and scaremongering based on what some FS98 pilot has said on here..

The media can go to hell! They are usually poorly qualified to understand air accident investigations, they like simple, dramatic stories and will make great logical leaps with little or no supporting data. We need to let the BEA and the other organisations assisting the investigation do their job thoroughly and not heap pressure on them to come up with hasty opinions just to feed the media beast.

[SFKL]

"these look like classic organic-rich (i.e. intensely black) shales to me and hence is their naturally colour. The more resistant, thin, lighter coloured rocks (seemingly uncharred) are white-yellow sandstone layers."

I walk a lot in this area and confirm this. The ground is a loose, friable clay/shale with isolated pieces of sedimentary rock. It's usually dark grey to black. Black appears more when cut open or if wet. Scrambling on it is hard work as the ground if heavily ravined and breaks up easily and falls apart. Landslips and erosion are common after rain/thaw. The detailed landscape can change from year to year as features collapse or wash out.

I'm surprised to see no main impact point. I think it possible significant amounts of aircraft parts lie under shale that has broken off and fallen on top. Possibly the FDR has been buried in this way.

[hum]

Of course you can simulate explosive decompression. Every military pilot has to go through it. I went through the altitude chamber several times during my career in the Army, including explosive decompression. Yes, it's disorienting....... Something else happened to this crew.

I too have done this in a previous life. But if you check your logbook as I just did I think you will find it was not from 6k to 38k. I am also certain it would not have been air at -40c (possibly at 350kts) coming at you. I seem to recall the most uncomfortable thing about my explosive decompression experience was the stench of the previous night's Ruddles...
I reckon the real thing is very different :-/

[nnc0]

All these comments about what happens in an explosive decompression - my first hand experience as the flight test engineer (B744) and caught not paying attention - when those valves were opened I was unconscious in less than 15 seconds - I remember the world getting very slow but that's it. Woke up around 8 000 ft somewhere if I recall. Barely functional the rest of that day.

(I was biking about 70 K a day back then and in great shape)

[G-CPTN]

Whilst realising that this aircraft suffered a tremendous impact, is it possible that even greater protection for the CVR and FDR might now be considered - such as a detachable capsule?

[keithl]

Hum: the mention of Ruddles gives yr post authenticity, all right! But my log book says 25k - 45k and later, 27k -56k. So not all were the same.

Fonsini: in your hypothesis, 7700 would not be the appropriate squawk.

[SLFplatine]

From an anonymous comment on avherald:

CVR data has been read. It seems structural failure (windshield? not determined yet)..It was quick... sound of cracks,but crew initiated emergency descent by autopilot and then they weren't heard anymore. Autopilot was on during whole descent, but disconnected automatically shortly before impact when GPWS alerts appeared.

an anonymous comment -all you need to know

another bit said to be from the same avherald (The Aviation Herald avherald(.com) is the website) posted several the pages back indicated that some data has been recovered from the FDR -Hello?

The at the present story (not the comments thereto) from said same avherald.com website states:
When confronted by journalists with rumours originating in Finnish media quoting Finland's CAA about a burst windshield, the BEA said they have no such information.

[GlobalNav]

@G-CPTN

When, where and how would a capsulized recorder be "ejected" for the sake of saving the data? What would trigger it and what about the lost data prior to impact?

Just asking.:confused:

[wiggy]

I claim to accept the need for extreme prudence by the head of such an organisation in such circumstances as these.

I was however surprised that:

i) He said that he hadn't listened to the cockpit recording at all himself almost 8 hrs after it arrived on site.



He's the head of the organisation and judging by the TV coverage in the last 24 this gent has been working flat out (interviews, statements to French TV, meeting with the politicians) since the accident happened. I suspect he's been far too busy to listen to recordings, even if it was part of his job spec.

[GlobalNav]

We have as yet insufficient information to establish a cause or even contributor to this tragic event.

But if there is any benefit from all the educated speculation, perhaps it is motivation to pilots still flying to review the emergency procedures for a decompression and be better prepared for such an unlikely - but still possible - event. First actions are critical.

I think that might be the kind of reaction our successful Captain Sullenberger might encourage.

[aterpster]

BigFrank,

I claim to accept the need for extreme prudence by the head of such an organisation in such circumstances as these.

I was however surprised that:

i) He said that he hadn't listened to the cockpit recording at all himself almost 8 hrs after it arrived on site.

ii) He refused to say if the voices were speaking in English or German

He's doing his job. The CVR is probably in Paris by now, being carefully disassembled, properly set up in a specially equipped sound proof room, then preferably having a full CVR team present to listen to the recorder.

That's the way it's done at the NTSB. I resume the French follow a very similar protocol.

[dlen]

Africanskies seems logical

All the emergency descend actions: set FL100 or secure altitude and initiate descend with AP, deviate from course, emit emergency message 7700, set passenger belt sign, let passenger oxygen masks fall down, could be initiated by one single command.

[frg7700]

As a FWIW there have been multiple interviews broadcast on French TV with the several eyewitnesses (farmer, local villagers) who saw the A320 in the moments just before it crashed. All were deeply shocked by what they witnessed but not one, not a single one, mentioned another aircraft in the vicinity..... I wonder where the Mail/Twitter found "their" eyewitnesses....frankly I'd call BS on that story

To be honest the first eyewitness report I heard, sounded like a 'phoner, on the Beeb yesterday the witness mentioned that he had seen several fighters soon before and thought the Airbus was another at first. Presented purely for balance.

[GlobalNav]

This question of 8 minutes vs. 18 minutes puzzles me. Likewise the media story about descent from 28,000 ft - IF the flight tracker was anywhere near accurate, which shows approximately 3 minutes at FL380 level off, then a descent at around :31 or :32 after the hour, end of data around :41 or :42 after the hour. A significant contradiction.

[threemiles]

Bear in mind ACARS overland is typically crude VHF unencrypted data transfer, which spotters / ham radio types can receive AFAIK? So if anything dramatic was sent, somebody might have said?

I would think the BEA will prioritise what they do have in conventional data sources (CVR, FDR, Mode S, ADS-B, ATC etc.). AF447 resorted to ACARS due to a high level of integration, and absence of other sources...

LH a/c do send only very limited operational ACARS data due to a major disagreement with the pilot's union. Data are considered as personal and performance data of the flight crew that the employer may not have access to without proper request and worker's council approval.

All LH ACARS messages are encrypted.

[Ian W]

yes, a lot .

It is quite traumatic for a controller I can tell you when you watch an aircraft you control go down.

This is a point that is not appreciated by many. Having someone die on your frequency is a very unpleasant experience and leads to continual thoughts that "perhaps had I done something differently...." It is even worse, when, as often happens, the flight crew is known personally to the controller(s).

[Easy Street]

Would the cabin crew have expected any communication from the flight deck following a depressurisation? I can see a terrible image of all pax and cabin crew sitting there with their oxygen masks on, waiting for the aircraft to level off. At what point would anyone think to ask whether the flight deck crew were OK, and try to gain access to the cockpit?

[Eaglebaby]

A bit like CRM...it teaches you to never be too sure about your knowledge never mind how long you have been there....why not listen to a "younger" opinion. It can be wise not to be too self confident/arrogant.

[Rotodyne]

I think the blackened mountainside is just the rock colour.

I have been to the area several times. After heavy rain, the Ubaye river is so black it looks like used engine oil. That is all runoff from the same mountains.

[kafky]

Pace, that data on suicide is largely inaccurate. This is a real issue, much more frequent we would like to. Last year, Namibia crash, there are strong evidences of suicide.
The main problem is that too many consider this exceptional and rare, so there is no awareness protocol to evaluate and prevent.

http://avherald.com/h?article=46c3abde/0010&opt=0

[AfricanSkies]

Africanskies seems logical

All the emergency descend actions: set FL100 or secure altitude and initiate descend with AP, deviate from course, emit emergency message 7700, set passenger belt sign, let passenger oxygen masks fall down, could be initiated by one single command.

That's it. After perhaps a delay to see if the pilots react first. If they don't then do the necessary actions. Including intelligent MSA settings as per terrain database. And avoid weather and avoid mountains and avoid other aircraft. It's aware of all of these things via its radar, GPWS & TCAS. All the data is there it just needs a macro system to link all the threads together.

If you extend that train of thought it wouldn't take much but software changes to enable a ground based pilot to set up the approach and auto land at a safe place.

[Cagedh]

Would the cabin crew have expected any communication from the flight deck following a depressurisation? I can see a terrible image of all pax and cabin crew sitting there with their oxygen masks on, waiting for the aircraft to level off. At what point would anyone think to ask whether the flight deck crew were OK, and try to gain access to the cockpit?

IF this turns out to be a drama with two unconscious pilots in a de-pressurized cockpit, that would become a very important question.

[Teddy Robinson]

We have the media, popping up talking heads so that they can somehow claim a scoop. Surely it is time for professionals in this industry to take a stand and speak with a common voice.

The only information we have is that the aircraft crashed at this location and that nobody survived.
As soon as the investigators have information to release to the media, it will be released. END OF.

It is high time that more respect is shown for the families of those who lost their lives, by the media as well as other speculators and theorists.

[ILS27LEFT]

Explained in simple words.
As soon as cruise height was reached the problem started, critically this was a sudden event likely linked to pressure: any loss of structural integrity (e.g. windscreen or other) started in coincidence with reaching max cabin pressure differential with the outside pressure. This timing cannot be a coincidence, the rest is hypoxia of all those on board whilst pilots being unable to do anything else except start descending; heading and speed remained constant until impact. No communication, aircraft continues with pre-set heading and speed: this is typical behaviour of aircraft with unconscious pilots in cockpit. It has happened before.
I have no doubts this was hypoxia (or unconscious pilots for any other reason). The fact that ATC lost contact and it quickly happened shortly after reaching altitude it would reinforce the hypoxia theory as a consequence of decompression, possibly caused by structural failure. I would exclude external factors at that altitude, the problem coming up at 1030/1031 time would confirm internal/external pressure extreme difference as likely trigger of decompression, in coincidence with max stress on structure, loss of fuselage integrity (aircraft still perfectly able to fly) with subsequent rapid hypoxia. To react to a decompression at that altitude is not as easy as thought or simulated, especially if cockpit environment is disrupted by the cause of the decompression (e.g. air coming in at very high speed). I have no doubts that these were excellent pilots who were not given a chance to follow standard simulator procedures, which can never cover all "real" scenarios.

[wiggy]

IF this turns out to be a drama with two unconscious pilots in a de-pressurized cockpit, that would become a very important question.

It's an important question but it was sort of covered earlier .... If there's a decompression and the aircraft doesn't start descending fairly promptly then it's probably reasonable that the Cabin Crew take some action and some are trained to do so

OTOH if there there's a decompression and the Flight Crew do start an emergency descent then one of the last things they then need is a Cabin Crew member trying to access the flight deck or trying to contact them via interphone.....it's nothing personal, but safely managing an Emergency descent can rapidly fill up the "capacity bucket".

Of course if you still want to go through the "what ifs" you then have to ask yourself - in the worse case if a cabin crew member somehow does gain access to the flight deck and finds that the aircraft is in an emergency descent with all pilots incapacitated what would they (the cabin crew member) do in the time available??

[malr]

We think about the most likely scenarios first. Extraordinary claims require extraordinary proof, etc.

This reminds me of an axiom in medicine: When you hear hoof-beats, you look for a horse, not a zebra.

[kwh]

In the light of more than one recent catastrophic incident where it seems at least possible that a depressurisation causing crew incapacitation was a significant factor, is it time for the automatics on modern passenger jets to be fitted with a software system that executes a pre-set sequence if certain conditions are true? For example, if cabin altitude is greater than 10K feet, and no significant control inputs or crew actions have been detected for a period of x minutes (where x is some agreed time period long enough not to be prone to false positives in the event of a crew responding normally to a depressurisation event), then would it be a good idea to let the automatics first announce to the flight deck that they are about to take control if nobody pushes a button in the next ten seconds, and then

1. Set a unique 'This is George, I have taken over because the crew is apparently incapacitated through hypoxia and this aircraft will be executing the standard set of pre-planned internationally agreed manoeuvres in ten seconds time' transponder code...

2. Terrain permitting, commence a circling descent to 10K feet, and hold altitude at 10K indefinitely until either a human wakes up and takes control or the engines flame out.

3. If terrain does not permit a circling descent to 10K, do something else sensible, standard and pre-agreed to get to a place where terrain does permit, and then descend/circle etc...

It _seems_ to me as SLF that at the moment there is a single point of failure, in the event of rapid decompression at high enough altitude - if for any reason, from mechanical failure to human error to who knows what, the person/people in the hot seat [and it is person singular if the other pilot is in the khazi] doesn't get oxygen out of the mask they put on their face when the cabin loses pressure, basically everybody on board the plane dies, possibly several hours later, possibly sooner if the aircraft starts descending before the pilot passes out, but their fate is irrevocably sealed. Against that, a 'dead man's handle' device might be a potential life-saver, no?

[alistair®]

The only information we have is that the aircraft crashed at this location and that nobody survived.
As soon as the investigators have information to release to the media, it will be released. END OF.

We hear this time and time and time again, on every single accident thread. It's a RUMOUR network, so either people just accept that for what it is (speculation and theory), or the forum is locked away to pilots only. I don't see the point of comments like yours (though this will probably be deleted anyway!)

[NigelOnDraft]

Originally Posted by Easy Street

Would the cabin crew have expected any communication from the flight deck following a depressurisation? I can see a terrible image of all pax and cabin crew sitting there with their oxygen masks on, waiting for the aircraft to level off. At what point would anyone think to ask whether the flight deck crew were OK, and try to gain access to the cockpit?
IF this turns out to be a drama with two unconscious pilots in a de-pressurized cockpit, that would become a very important question. As Wiggy says, Helios lead to a change in some SOPs - certainly ours, for an apparent non-reaction to a decompression.

If this turns out to be a partial / incomplete reaction to a decompression, and there is something feasible the CC could have done (e.g. rouse pilots), then I suspect we will see SOPs change again. But there is only so much second guessing you can expect CC to do over our job.

As I posted earlier, if there was a complete decompression, pilots not on oxygen, and it took 5mins or more to get below ~25K' Cabin Alt, I am afraid my limited AvMed knowledge indicates your SOP is not going to further involve the pilots :oh:

[BigFrank]

"He's the head of the organisation and judging by the TV coverage in the last 24 this gent has been working flat out (interviews, statements to French TV, meeting with the politicians) since the accident happened. I suspect he's been far too busy to listen to recordings, even if it was part of his job spec."

I take the point you make in the first sentence.

Yet I beg to disagree with the conclusion.

Given the magnitude of this catastrophic accident and given also the possibility of these cockpit recordings throwing significant light on the "mysterious" causes, I stand by my observation that his failure to listen to the cockpit recording is very striking.

[mm_flynn]

Would the cabin crew have expected any communication from the flight deck following a depressurisation? I can see a terrible image of all pax and cabin crew sitting there with their oxygen masks on, waiting for the aircraft to level off. At what point would anyone think to ask whether the flight deck crew were OK, and try to gain access to the cockpit?

Assuming for a minute the depressurisation/hypoxia scenario is correct, the flight path seems to have been exactly as the cabin crew would have expected, until they descended below 10,000 feet. So for a minute or two people may have thought 'we are getting close to the ground, why are we still descending?'. The FR24 flight path then suggests the aircraft levelled off c 3000 feet above the local terrain and then a minute later .... when the 350 knot aircraft intersected the rapidly rising terrain.

I would have thought the cabin crew would have been focusing on breathing, making sure the passengers didn't do anything dumb, and hoping to get warm soon for most of the descent and letting the flight crew get on with resolving whatever problems they were dealing with.

[Chris_Clark]

The Guardian reported this at 18:26:

Jouty said it was too early to give details of the cockpit recording. However, he said the information investigators had put together suggested the plane had not exploded and did not suffer a “classic decompression situation”

Voices heard on recorder from cockpit of Germanwings plane crash | World news | The Guardian (http://www.theguardian.com/world/2015/mar/25/recordings-voices-alarms-extracted-cockpit-crashed-germanwings-flight-4u9525)

[Greasy Monkey]

If there was an explosive decompression, that descent took too long. The oxygen generator masks for the passengers would not have provided sufficient oxygen at sufficient pressure to keep them awake for that duration to get below 25,000'. At 38,000' you are really looking at pressure breathing apparatus if spending too much time up there.

I am amazed when I read of PJ crews, cruising at FL510 for example. Get a blowout up there you are a gonna. Period. Forget about the passengers, they will most likely be dead very quickly. End of.

From what I can find, it is the lower-left forward fuselage, I would assume as close to the flight deck as possible.

[cockpitvisit]

Very few suicides take 150+ innocent lives along with their own. It's literally is almost unthinkable and certainly exceedingly rare.


Suicides are not rare at all (compared with the overall frequency of fatal crashes in the cruise phase).

There were 3 pilot suicides with killed passengers in the last 20 years (EgyptAir 990, SilkAir 185, LAM 470).

Compare this with just 2 fatal mechanical failures during cruise flight in the same time period (China Airlines 611 and Helios 522).

[ironbutt57]

If the pilots were indeed incapacitated by hypoxia, is it possible that one or both could regain consciousness upon reaching lower altitudes?

Yes Navcant...entirely possible....

[Pontius Navigator]

If the pilots were indeed incapacitated by hypoxia, is it possible that one or both could regain consciousness upon reaching lower altitudes?
Asked and answered earlier. The short answer is maybe. The longer answer is it depends - fitness, time unconscious, time to regain useful consciousness.

[ECAM_Actions]

Germanwings crash investigators review cockpit recordings found on black box | World news | The Guardian (http://www.theguardian.com/world/2015/mar/25/recordings-voices-alarms-extracted-cockpit-crashed-germanwings-flight-4u9525)

The Airbus A320 that ploughed into an Alpine mountain flew “right to the end”, the investigators said, and did not explode mid-flight. It also appeared not to have suffered a sudden drop in pressure.Jouty said it was too early to give details of the cockpit recording. However, he said the information investigators had put together suggested the plane had not exploded and did not suffer a “classic decompression situation”.Asked about the aircraft’s apparently controlled descent before it crashed, he added: “The path is compatible with the plane being controlled by pilots, except it’s hard to imagine that a pilot would send an aircraft into a mountain, and it’s compatible with an autopilot.”

He was unwilling to give any more information.
Rémi Jouty is a BEA spokesperson.

Make of that what you will.

[Lonewolf_50]

Interestingly the Cirrus SR 22 has a feature whereby if there is no crew input to certain systems after a set period, the autopilot commences a descent to 10,000' This might cause some trouble over certain mountain ranges ... :eek:
Vertical Speed:
1. AP executes 90degree left turn and pitch down.
2. Speed controlled near Mmo/Vmo and level off at 15,000'
3. EMER DESCENT annunciated on PFD
Fewer mountain ranges cause trouble with this.

I disagree with kwh that such over-automation is needed. Additional complexity for what value that cannot otherwise be mitigated? Further this point, the recent concerns over Normal Law Alpha Protect taking control from pilots (due to a malfunction) reminds us that with every feature like this you put in, you induce the potential for yet another novel failure mode.

Fix one perceived problem and raise another that you won't discover ... until it happens, perhaps in flight.

Further a point ia raised a bit earlier:

Task saturation/task focus.
Whatever went wrong at altitude, there is the potential, as with AF 447 and the recent Indonesian accident, that the two pilots were consumed with the first two prime directives of flying -- aviate navigate -- (and part of aviate being get plane in control and fix / trouble shoot what's wrong with it) that their task loading did not get to the communicate/squawk change step. While in those two cases upset looks to have been the core problem, and in this case not, that doesn't mean that a serious malfunction didn't occur that wholly occupied the attention of the flight deck crew.

If you go back about ten pages and re read the strange case of the leaking fluid that sickened the captain and the FO in the terminal environment ... a rare but nasty malfunction.

[SAMPUBLIUS]

this link may help

When Windshields Fail | Business Aviation content from Aviation Week (http://aviationweek.com/business-aviation/when-windshields-fail)

[BigFrank]

"He's doing his job. The CVR is probably in Paris by now, being carefully disassembled, properly set up in a specially equipped sound proof room, then preferably having a full CVR team present to listen to the recorder.

That's the way it's done at the NTSB. I resume the French follow a very similar protocol."

As one who is not professional in the airline world I find this confusing.

The implication of what you write is that the initial process of listening to which the Head of BEA (as I understand the gentleman's rôle) alluded in his press conference took place in less than optimum conditions and away from the main base.

Yet I understood, perhaps wrongly, that the device was delivered to the main base at 9:45 am and that the press conference took place there some 7+ hours later.

Edit:
Based on a doubt raised by a recent post on here which describes M Jouty as a BEA spokesperson, I found press reports on-line from last year which confirm my understanding that he is in fact the Head of BEA.