Volo Easyjet rientra a Malpensa causa fumo in cabina

[mxp98]

Aereo EasyJet, fumo in cabina dopo il decollo
(ANSA) - MILANO, 15 NOV - Un volo EasyJet decollato da Malpensa e diretto a Malaga, in Spagna, è stato costretto a un atterraggio nel primo pomeriggio in quanto nella cabina di pilotaggio si era creato del fumo sulla cui causa si stanno ancora compiendo accertamenti. L'aereo, con a bordo il solo equipaggio, era decollato alle 13:45 e pochi minuti dopo ha segnalato alla Torre di controllo la presenza del fumo, chiedendo il permesso di atterrare. Cose che è avvenuta poco dopo le 14. I membri dell'equipaggio sono stati portati in infermeria per un'intossicazione.(ANSA).

http://www.ansa.it/lombardia/notizie/20 ... f0c67.html

[I-Alex]

Chissà cosa è successo


Inviato dal mio iPhone utilizzando Tapatalk

[spanna]

la domanda che nasce spontanea e': le famose maschere di emergenza che dovrebbero uscire automaticamente in caso di emergenza, sono uscite? Come e' possibile che si siano intossicati?

[easyMXP]

Io ho capito che il passaggio in infermeria è standard in questi casi, per controllo, ma non c'è stata una vera intossicazione.

Le maschere escono in caso di depressurizzazione con mancanza di ossigeno, non in caso di fumo.

[spanna]

stai dicendo che in caso di fumo le maschere non scendono automaticamente? Sarebbe assurdo.

[easyMXP]

Io non erogherei ossigeno in presenza di un potenziale incendio senza prima verificare se ci siano fiamme libere.

L'automatismo in caso di depressurizzazione è legato alla potenziale incoscienza di chi dovrebbe attivare il meccanismo, ma in caso di fumo il problema non c'è.

[mxp98]

Io non erogherei ossigeno in presenza di un potenziale incendio senza prima verificare se ci siano fiamme libere.

L'automatismo in caso di depressurizzazione è legato alla potenziale incoscienza di chi dovrebbe attivare il meccanismo, ma in caso di fumo il problema non c'è.

Esatto e aggiungo queste poche righe per completare il discorso:

While a cabin oxygen mask does provide supplementary oxygen, it also combines the oxygen with cabin air...meaning that passengers who are drawing oxygen through the mask are also breathing in cabin smoke.......

The masks we use in the cockpit are different than the masks used by passengers. The passenger masks are designed to provide a limited amount of supplementary oxygen, which is mixed with cabin air, in order to sustain life during an emergency descent. This is the only application for the use of oxygen by passengers; during a time when cabin pressure has been reduced and oxygen is an immediate lifesaving requirement, it's provided on an emergency-only basis, for a brief period of time.

This doesn't, as a rule, do anything for a passenger during a smoke or fire situation, as the passenger is breathing the cabin air. The same acids which attack mucus membranes in the nose, eyes, and mouth, still cause the stinging and burning. The same toxic vapors enter the airway, with or without the passenger mask.

The cockpit crew goes on oxygen quite simply because without the crew being able to see and breathe, everybody dies. It's in everybody's interest for the crew to be on oxygen.

In the cockpit, we wear a mask which completely seals. It prevents any vapors, fumes, smoke, or other dangerous aerosols from entering the mask when we breathe. We have several settings on these masks, one of which does the same as the passenger masks...it dilutes the oxygen intake with cabin air in order to prolong the duration of the available oxygen.

The other two mask regulator settings, however, don't use the cabin air at all. One is a 100% setting, and the other is an emergency setting in which not only is 100% oxygen delivered, but it's delivered under pressure, forcing air into our lungs in some systems, and in others providing adequate pressure to prevent any intrusion of outside gasses.

Over these masks a pair of smoke goggles can be worn. Some aircraft also use a special inflatable hood which goes between the windscreen and the pilot to enable the pilot to see out of the aircraft even when the cockpit is full of smoke.

[spanna]

grazie per le spiegazioni molto esaurienti

chissa' se sei in grado di dissolvere il dubbio che ho da sempre sulle maschere: quando gli assistenti danno spiegazioni dicono sempre di non preoccuparsi se il sacchetto non si gonfia, perche' l'ossigeno arriva ugualmente. Io mi sono sempre chiesto: ma allora perche' il sacchetto esiste? Se non serve che lo tolgano.

[mxp98]

@Spanna
Credo che tu possa trovare la risposta in questo post che ho copiato da PPrune:

Different kind of mask...a rebreather mask, vs. the nonrebreather mask in the airplane. Medical administration of oxygen, a drug, is a little difference than emergency supply of oxygen in an airplane.

The bag may or may not inflate. The mask is a simplified non-rebreather mask with a maximum potential delivery rate of about 22 lpm flow. The bag acts as a resorvoir which does two things; it enables a larger volume of oxygen to be drawn with a breath, and it helps prevent flow-through wastage of oxygen between breaths.

How full the bag gets depends on one's rate of breathing. In a time of crisis, one tends to breathe in a panic; it's one of the first controls to go. The crisis claims our breath. That is, our body has been practicing breathing for our entire lifetime, but in a crisis the process of simple respiration is accelerated in a panic. Rather than allowing time for the bag to inflate, we suck the air down as fast as we can...and we see no inflation.

I worked as a firefighter. This involved wearing self contained breathing apparatus...SCBA gear. I've seen firefighters empty a tank in five minutes. It's not hard to do, breathing hard, working hard. It should last about fifteen, and it can, if one breathes carefully and slowly. This takes practice however, and conserving air isn't first and foremost on the average passenger's mind.

Rather than giving a detailed explaination, the briefing is usually "the bag may or may not inflate, but you will be receiving oxygen none the less." As a passenger, you really don't need to know the flow rate or function of the mask. Just that it's delivering oxygen, and that you shouldn't worry if you don't see the bag inflate. You're told that to prepare you...so you don't have to question it later.

[The bag does two things, then. Given a little time and a good seal on the mask, it will inflate between breaths. However, if there's no seal on the mask (as often there isn't), then enough oxygen is escaping the the mask that air only flows through the bag, rather than inflating it. Not a big deal. If you do get a good seal, rather than simply letting the pressure build in the mask and then push out and be wasted, the bag acts as a resorvoir. It contains the oxygen between your respirations, allowing it to go unwasted.

It's worth noting that at altitude it's not the amount of oxygen that's important to you; it's the pressure. Vapor at any altitude has a pressure, and for any given altitude, oxygen makes up about 21% of that pressure. At sea level and for most people anything up to 10,000 to 14,000, the partial pressure of the oxygen in the atmosphere is sufficient to pass through the cell walls in your lungs and participate in the respiration process...the exchange of waste materials from your bloodstream for fresh oxygen for your hemoglobin.

At higher altitudes, even though you may be supplied a higher concentration of oxygen, insufficient partial pressure may be available to permit the respiration process. Simply put, the gas (oxygen) is there, but you can't really use it. Never the less, get on it as soon as you can and stay on it. At higher altitudes, the time of useful consciousness is very low, close to 5 to 15 seconds during a rapid decompression. The potential for loss of consciousness is very high, and you'll need that mask on your face as you descend...even if you're not awake for the descent.

You're always told to pull the mask toward you. It took some time to dawn on me that this wasn't just a way of telling me to put the mask on. You must pull the mask because there's a lanyard attached to the mask. This lanyard pulls a pin in the valve assembly above your seat, allowing oxygen to flow to the mask. When the masks deploy, it's done because oxygen pressure has been let into the lines leading to the manifold above your seat, and that oxygen pressure releases the latch. It doesn't provide oxygen to the mask, however, until you pull on it, pulling the pin in the manifold and causing the oxygen to flow. For the masks simply hanging down, there's no oxygen flowing out of them, and you won't see the bags inflate on those either.

Where oxygen is very, very important is smoke in the cabin. You can live without water for days, without food for weeks, and without sex for...unfortunately a very long time. But not oxygen. Just minutes. When synthetics begin to burn they form toxic gasses which range from Phosgene gas to carbon monoxide to hydrochloric acid...which constitutes when the smoke contacts your mucus membranes such as your eyes, nose, mouth, and airway. Smoke can overcome you very quickly, so getting on the oxygen is important. This isn't a time to worry if the oxygen is flowing because the bag looks flat...so you're told in advance that it may or may not inflate.

http://www.pprune.org/questions/340580- ... flate.html