Airbus A320 crashed in Southern France

[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"


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]

Originally Posted by NigelOnDraft

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]

Originally Posted by ia1166

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]

Air pressure on flight deck

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]

Originally Posted by ia1166

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]

FDR

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

[procede]

Originally Posted by 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.

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/minist...n/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]

Forward pressure bulkhead - proposed AD

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]

NY Times is reporting FDR memory card missing

"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...?