Passengers on Jet flight bleed after crew forgets to maintain cabin pressure

[Buzzing]

This from an Indian news site ... I'm unable to post links just yet.

A Jet Airways flight between Mumbai and Jaipur had to return to Mumbai this morning due to cabin pressure dropping that led to bleeding from nose and ear of passengers on the flight.

An official of the Directorate General of Civil Aviation (DGCA) said that the Jet Airways B737 aircraft operating flt 9W 697 of 20th Sep 2018 (Mumbai-Jaipur) had air turnback to Mumbai, as cabin pressure fell due to the fault of cockpit crew.

“During climb, crew forgot to select bleed switch due to which cabin pressurisation could not be maintained. As a result, oxygen masks got deployed,” said the official.

The official added that as per initial information, few pax have nose bleeding.

“Out of 166 passengers on board, 30 have reported nose bleeding, few have ear bleeding and some are complaining headache. All the affected passengers are being attended to by the doctors at the airport,” the official further said.

Jet Airways could not be immediately contacted for the story.

[jack11111]

Where is the video of all these bloody folk? Of 166 pax, someone must be a videographer.
.

[Buzzing]

Where is the video of all these bloody folk? Of 166 pax, someone must be a videographer.
.

Do a google search with the thread title and look for the videos.

The video is in Hindi with in-cabin footage of pax with masks on.

[Buzzing]

Where is the video of all these bloody folk? Of 166 pax, someone must be a videographer.
.

Hopefully now I can post the link ...

https://www.youtube.com/watch?v=lRqpUT0XJ8g

[KingAir1978]

An official of the Directorate General of Civil Aviation (DGCA) said that the Jet Airways B737 aircraft operating flt 9W 697 of 20th Sep 2018 (Mumbai-Jaipur) had air turnback to Mumbai, as cabin pressure fell due to the fault of cockpit crew.

“During climb, crew forgot to select bleed switch due to which cabin pressurisation could not be maintained. As a result, oxygen masks got deployed,” said the official.

The official added that as per initial information, few pax have nose bleeding.

“Out of 166 passengers on board, 30 have reported nose bleeding, few have ear bleeding and some are complaining headache. All the affected passengers are being attended to by the doctors at the airport,” the official further said.



Always good to see that the authorities really uphold the 'just safety culture'... Investigation? Nahh... way overrated. Let's just throw the pilots under the bus.

[JohnMcGhie]

Why is this system not fully automatic?

If the FADEC has full authority over the engine, why doesn't the environmental control system have full authority over the cabin pressure?

Surely Mr. Boeing has some kind of a warning: "Excuse me, you're climbing without cabin pressure, have you forgotten something?"

Surely there is a serious warning on the flight deck long before the rubber jungle?

Surely the cabin staff are alert to this? Can't they prod the guys up the pointy end?

We have had pressurisation failures for decades: why has this not been dealt with?

What am I missing here?

[FYSTI]

Why is this system not fully automatic?
...
What am I missing here?
History
A VW Kombi retrofitted with a V8 engine and an Atari as one trainer used to remark...

Everything you request could be installed tomorrow, it could have a nice overhead panel and EICAS. Problem is some large operators won't buy it as it would be a new type for their crews, hence training costs.

So we still are still stuck with the Kombi,..

[Right Way Up]

Could have been far worse.........Helios accident comes to mind.

From memory the cabin pressurisation warning on the flight deck is the same as the takeoff config warning which can lead to misunderstanding.

[nicolai]

The problem seems not so much to be that there was a pressurisation problem which does happen, especially on the 737 with its badly integrated mix of controls and indicators, but that the crew handled it badly.

Indeed, how close was this to Helios (Indian edition) ?

[meleagertoo]

Almost 20% of the pax suffered bleeding as a result of a slow depressurisation to a mere 12-14,000 feet or so? Really?

Sounds highly unlikely to me, bleeding is surely pretty unusual even in a fast depressurisation?

I wonder if the word "bleed" got carried over from the pneumatics to the respiratory system by an over-zealous journalist?

I can well imagine the flight-deck's ears will be bleeding after they've listened to what their Chief Pilot has to say!

[meleagertoo]

Why is this system not fully automatic?

If the FADEC has full authority over the engine, why doesn't the environmental control system have full authority over the cabin pressure?

Surely Mr. Boeing has some kind of a warning: "Excuse me, you're climbing without cabin pressure, have you forgotten something?"

Surely there is a serious warning on the flight deck long before the rubber jungle?



It certainly is automatic, but just as the FADEC can't control a non running engine if you haven't given it any fuel the pressurisation system has nothing to control if you leave the bleed switch off and give it no air.

Warning? You bet there's a warning! A loud and very insistent intermittent horn but as said above it's the same as the t/o config warning and can result in a usually fairly short conversation that begins with "Why is the config warning going off at this altitude?" and ends rather abruptly with a scatalogical exclamation shortly thereafter. It doesn't give you a lot of time though, iirc the horn goes off at 10,000ft and the rubber jungle deploys at 14,000. Plenty of time for most crew to remember the other meaning of the config horn, something that is drilled into every 737 pilot.

It isn't a system failure, the systems all worked just fine as they were supposed to. The only thing that needs fixing is a crew who make a critical mistake, fail to spot it and additionally forget critical technical knowledge at the critical moment when the machine is urgently trying to tell them something. The usual fix is rockets of variable size inserted in the fundament with variable degrees of empathy.

I agree you would think that both the cabin crew and the pilots would notice the unusual ear sensations but the cc may be reluctant to call the flight deck for various reasons (ie below 10,000ft if that's SOP, or simply a steep authority gradient in the company/culture in question).

[DaveReidUK]

Almost 20% of the pax suffered bleeding as a result of a slow depressurisation to a mere 12-14,000 feet or so? Really?

Having spent many happy hours at FL150 in unpressurised aircraft (albeit ones that took rather longer to get that high than a 737 does), I'm surprised at those injuries, too.

Particularly as FR24 suggests the JAI didn't in fact get above FL110.

[krismiler]

Was the pressurisation turned back on ? A sudden and rapid increase in cabin pressure could cause these symptoms.

[waflyer]

Bet: Krismiler's got it right!!

[Matey]

Boeing have addressed the issue of incorrect bleed selection on the MAX. BLEED lights will illuminate with associated Master Caution if the bleed switches are in an incorrect position 45 seconds after the flaps are up after take off.

[Old Fella]

Having spent many happy hours at FL150 in unpressurised aircraft (albeit ones that took rather longer to get that high than a 737 does), I'm surprised at those injuries, too.

Particularly as FR24 suggests the JAI didn't in fact get above FL110.

The "Rubber Jungle" should not have deployed automatically until the Cabin altitude reached 14000'. As for the excuse that the Cabin Pressure Warning is similar to the Take-off configuration Warning,
surely the crew should be smart enough to check the Cabin Pressure before reaching 14000'. The warning would have sounded as the cabin passed 10000'.

[fdr]

Us humans suffer from expectations of outcomes and that lowers our defences from having done the same routine many times, and having had successful outcomes routinely. Success breeds complacency, but it still better than having too many unsuccessful outcomes. This isn't normalisation of deviation, it is the fact that we get comfortable with what we are doing.

Do we bother anymore with the simple flaps/trim/pressurisation/spoilers? And if we do, (and not because we are OCD..) do we always do it? How often do we forget completely a checklist, or forget to complete a checklist? ECL's assist in that regard, but even ECLs can be overlooked.

Passing 10K, there was a time that the pressurisation was always checked, seems like a fair time to do a final check, but then if we are distracted in the first place, we may well be distracted for the next set of defences.

Systems relying on multiple switch selections to achieve the outcome, and where those also get done during relatively high workload periods have the need for good independent alerting systems in order to have reliability. Without that, we will occasionally prove that the flight crew are indeed human.

The barotrauma may well have occurred from re-pressurisation, the rate of change would probably be higher, but the sinus hates decomp if blocked, ears blow wax out in that case, but re-press on the ears can mess up the inner ear mightily. All are options, but you may have a sound point. That is the reason we do low rate descents after completing the emergency descent... As an aside, one military jet I fly is unpressurised, and that goes up to 35K occasionally, mainly I top out at 25K. Doing vertical manoeuvres with no press is interesting the first time, but really doesn't cause much discomfort, and that is at ROC/ROD around 15KFPM at 350-450Kts vertical. It is less fun than a 2.5" diff but it doesn't seem to hurt IF you don't have a cold. A percentage of every cabin is going to have compromised sinuses etc, so injuries are going to happen in a decomp/unpressed event.

I wouldn't be shooting the crew for being human. They are probably the least likely crew to ever climb unpressed in the near future.

[Timmy Tomkins]

The problem seems not so much to be that there was a pressurisation problem which does happen, especially on the 737 with its badly integrated mix of controls and indicators, but that the crew handled it badly.

Indeed, how close was this to Helios (Indian edition) ?
Similarities for sure but Helios had additional issues (the whole airline was a mess) with two pilots of differing nationalities using a shared second language and a captain who got out of his seat to see if the pressurization warning was overheating avionics due to a cooling fan failure; before passing out. There were issues with both crew members then as well, who knows what the crew dynamics were here but a culture in which two pilots from the same operator came to blows recently, doesn't bode well.

[.Scott]

Was the pressurisation turned back on ? A sudden and rapid increase in cabin pressure could cause these symptoms.This is a good question.
Decades ago, I did the Physiological Training Seminar that was offered to pilots by the FAA. The one I attended was at Andrews AFB and there were 16 of us in the class.

One of the exercises was a rapid decompression from 8,000ft to something over 30,000ft. That rapid decompression occurred over 4 or 5 seconds. It was meant to simulate what might happen in an airliner that lost a window. We donned our masks and stayed at 30+K for a few of minutes before the recompression. The recompression took less than 5 minutes. All 16 of us did this (in two groups of 8). No one suffered any bleeding.

I can think of two things that were different: First, we may have been exposed to the high altitude longer than the Jet Airways passengers. Second, the air we were breathing may have been significantly colder.

BTW: I notice that they still offer this course - but in a toned down version and only in Oklahoma. FAA Physiological Training Seminar (https://www.faa.gov/pilots/training/airman_education/aerospace_physiology/)

[misd-agin]

Was the pressurisation turned back on ? A sudden and rapid increase in cabin pressure could cause these symptoms.

Similar event at our company. Rapid double bleeed engagement at altitude resulted in injuries. That’s why normal bleed establishment is done one at a time after a ‘bleeds off’ takeoff.

[PukinDog]

The "Rubber Jungle" should not have deployed automatically until the Cabin altitude reached 14000'. As for the excuse that the Cabin Pressure Warning is similar to the Take-off configuration Warning,
surely the crew should be smart enough to check the Cabin Pressure before reaching 14000'. .

One would think. Incredibly, however, there are pilots who don't or won't check even obvious killer items like flight control movement before T/O, T/O power achieved during, or the pressurization system pressurizing during the climb unless directed by checklist and only when it does. Sometimes, not even then.

[krismiler]

Suddenly reacting and doing something that should have been done earlier without reassessing the current state of affairs can cause even worse problems.

For example: forgetting to retract the landing after take off, suddenly realising it and operating the lever at a speed in excess of VLO could damage the gear doors. Assuming VLE hadn’t been exceeded, slowing down to the correct speed before retraction would be the correct course of action.

Levelling off if at a suitable altitude and attempting to pressurise with a single bleed source, pack flow low and a selecting a reduced cabin V/S would avoid a sudden thump of pressure. Obviously a higher altitude would require descent rather than a level off.

Unfortunately we as human beings often have a knee jerk reaction without thinking first.

[underfire]

https://www.oneindia.com/india/jet-airways-flight-returns-mumbai-as-30-passengers-suffer-nose-ear-bleeds-2779344.html

interesting video from cabin

On a curious note, what is the pressurization rate vs climb rate? On many aircraft, especially the smaller ones, the climb rate always seems to outpace the pressurization rate.

[wiedehopf]

Have you read this yet:
Accident: Jeju B738 at Seoul on Dec 24th 2015, loss of cabin pressure and subsequent excess pressure (http://avherald.com/h?article=49158d84&opt=0)

Seems really similar except for the bleeding.
On the other hand with this thread it's not really clear what is going on.

[DaveReidUK]

On many aircraft, especially the smaller ones, the climb rate always seems to outpace the pressurization rate.

Isn't that whole point of pressurisation - that the cabin should climb at a lower rate than the aircraft does ?

[Prober]

Having twice experienced no pressurization on T/O - on 757 due icing up of the outflow valve - not only are there warnings for this, though I am not familiar with the 73, surely, surely! the crew would have noticed something strange immediately. I recall recognising the problem on rotation, not when the jungle fell on the pax. And that is not because I was a brilliant pilot (I wasn't, I don't think), but because I am a human being and not used to my ears being punished the way they were. Even if Jaipur was hot and high, it's not that high and there would have been going on ten minutes before the masks fell. We obviously do not have the whole story and so it can only be conjecture at this point.
Prober

[Flying Clog]

Once you've been to India, and been involved in aviating there, nothing surprises you.

[FalseGS]

The 737 is notorious for incidents arising from the intermittent horn, sometimes leading to tragic losses. Took Boeing half a century to fix the lack of any bleed configuration error warnings. As much as I love my plane, it really is stuck in the 60s.

[ManaAdaSystem]

The 737 is notorious for incidents arising from the intermittent horn, sometimes leading to tragic losses. Took Boeing half a century to fix the lack of any bleed configuration error warnings. As much as I love my plane, it really is stuck in the 60s.

I’ll be the first to admit that the 737 has a lousy warning system, but if you fly one and don’t understand the difference between the take off config warning and the cabin alt warning (even without the lights), maybe you should find another job.
How it’s possible to be a 737 captain and not know the difference, is beyond me. Helios should never have happened. Aircraft system knowledge, FAIL.