[Rahul Bhalgat]

Came across the following news:

Several passengers on a Jet Airways flight from Mumbai to Jaipur suffered nose and ear bleeding on Thursday after the crew "forgot" to turn on a switch that controls cabin air pressure, officials said.

"During climb, the crew forgot to select bleed switch due to which cabin pressurisation could not be maintained. As a result, oxygen masks got deployed," the official at aviation regulator, Directorate General of Civil Aviation, said.

The Boeing 737 aircraft returned to Mumbai due to "loss of cabin pressure" and the pilots have been taken off duty pending investigation, a Jet Airways spokesperson said.

[srishiva]

Originally Posted by Rahul Bhalgat

Came across the following news:

Just read about this. So much of un-professionalism. Last week on my flight from Amsterdam during landing, the brakes were applied so hard that everyone had to really try hard to hold our bodies back. Not sure if it was because landing was delayed on the run way. I hope these people take their jobs seriously.

[AlphaKilo]

Originally Posted by Rahul Bhalgat

Came across the following news:

An update on the same. The minister has taken some action and initiatives. Lets see how much fruit it bears and what the outcome of it would be.

Civil Aviation Minister Suresh Prabhu Thursday ordered a safety audit of all scheduled airlines and airports, amid recent incidents related to safety of passengers.

The development also comes on a day when several passengers on a Jet Airways flight from Mumbai to Jaipur suffered nose and ear bleeding after the crew "forgot" to turn on a switch that controls cabin air pressure.

Prabhu has directed officials concerned to prepare a comprehensive safety audit plan, which ..

https://economictimes.indiatimes.com...w/65885030.cms

[Chetan_Rao]

Noob question:

Why does the Aviation Ministry need to separately order an audit? Aren't periodic audits part of airport & airlines SOP?

[Rahul Bhalgat]

Originally Posted by Rahul Bhalgat

Came across the following news:

This incident also reminded me of the Helios flight where the ground engineer changed the cabin pressurization state to "Manual" from "Auto". He did it for carrying out checks in response to possible door leak reported by the pilots but he forgot to change it back to "Auto". The pilots too did not bother to check this in pre-flight checks, after-start checks and after-takeoff checks.

The pilots not only failed to check if the cabin pressurization is set to auto but also ignored the warning horn, which sounded at 12000 feet altitude.

The pressure inside the cabin was gradually lost. Everyone onboard was incapacitated and the aircraft continued to fly on autopilot till the engines starved. The aircraft then crashed killing all 121 onboard.

The pilots failed but one of the cabin crew attempted to control the aircraft but it was too late for him since he too was nearing incapacitation. Ironically, he was a qualified pilot serving as a cabin crew in search of job as a pilot.

[V.Narayan]

Originally Posted by srishiva

Just read about this. So much of un-professionalism. Last week on my flight from Amsterdam during landing, the brakes were applied so hard that everyone had to really try hard to hold our bodies back. Not sure if it was because landing was delayed on the run way. I hope these people take their jobs seriously.

A hard landing or tight braking could be for a dozen reasons which have nothing whatsoever to do with pilot performance or competence or alertness. A soft landing is not a safer landing as many passengers incorrectly believe. In fact apples for apples I would put my coin on a hard firm landing especially if there is wetness.

[TKMCE]

It is good that the safety audit has been ordered. It willl be great if the report is put in the public domain as well. The report on the Jet Airways accident at Goa is still not available in the DGCA website.

The "30 day" period seems too ambitious to do any serious audit. Clearly there are issues extending beyond the superficial if recent incidents are anything to go by and hopefully the 30 day period will be for a preliminary report only.

[Gannu_1]

Passengers experience nose, ear bleeding on Jet Airways flight 9W-697 from Mumbai to Jaipur.

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

Originally Posted by AVHerald

A Jet Airways Boeing 737-800, registration VT-JGS performing flight 9W-697 from Mumbai to Jaipur (India) with 166 people on board, departed Mumbai's runway 27 when the passenger oxygen masks were released. The crew stopped the climb at FL110, descended the aircraft to FL100 and returned to Mumbai for a landing on runway 27 without further incident about 40 minutes after departure. A number of passengers suffered from bleeding noses and ears and were checked by medical staff, a number of passengers were taken to a hospital.

The hospital reported 5 passengers were diagnosed with barotrauma of the ears.

India's Ministry of Civil Aviation reported 30 passengers were affected suffering nose bleeds and/or ear bleeds. The DGCA has been instructed to file its report into the occurrence immediately. The crew has been suspended pending investigation. The DGCA is following up on reports suspecting the crew forgot to turn on a switch needed for proper cabin pressure control.

Passengers reported there had been a very sharp drop of cabin pressure causing nose and ear bleeds, the oxygen masks were released.

AV Herald

Man, I feel for the passengers. Must have been a painful experience. :(

[SCORPION]

To the experts, is there a separate bleed air for maintaining the pressure inside the cockpit? Is there a separate package air conditioner for the cockpit? How come the pilots did not realize there was a drop in cabin pressure or there was something amiss with the Air Conditioning system? How come they never felt any symptoms like the passengers did?

[Jeroen]

Originally Posted by srishiva

Just read about this. So much of un-professionalism. Last week on my flight from Amsterdam during landing, the brakes were applied so hard that everyone had to really try hard to hold our bodies back. Not sure if it was because landing was delayed on the run way. I hope these people take their jobs seriously.

Originally Posted by V.Narayan

A hard landing or tight braking could be for a dozen reasons which have nothing whatsoever to do with pilot performance or competence or alertness. A soft landing is not a safer landing as many passengers incorrectly believe. In fact apples for apples I would put my coin on a hard firm landing especially if there is wetness.

Absolutely, these very smooth greaser that passengers enjoy and are praised on various Youtube video’s are not necessarily the safest way of landing.

You want to be flying or you want to have the wheel on the ground. The final phase of the landing is where the pilot rotates the aircraft a few degrees to slow the vertical speed of the aircraft as it gets close to the runway. That is also where the so called ground effect kicks in. Simply put, as the airplane gets close to the ground a cushion of air forms providing extra lift.

On commercial jetliners you need to actually fly the plane through the ground effect into the runway. On smaller planes, like the ones I fly, you bleed off forward speed whilst in the ground effect and the plane will stall and settle on the runway.

If you see a commercial jetliner making a “greaser” it is more likely the pilot got his final speed and rotation slightly off. You just don’t want to be halfway in between flying and wheels on the ground in this ground effect.

So pilots, but also auto-pilots are taught/programmed to set down with an appropiate vertical speed downwards. Practically that means a distinct bump.

That means you don’t float in the ground effect. You get you main gear on the runway so it can get traction (helping to line up in case of crab landing during crosswind).

Originally Posted by SCORPION

To the experts, is there a separate bleed air for maintaining the pressure inside the cockpit? Is there a separate package air conditioner for the cockpit? How come the pilots did not realize there was a drop in cabin pressure or there was something amiss with the Air Conditioning system? How come they never felt any symptoms like the passengers did?

I am not that familiar with the 737, but one thing is for sure, the pressure int he cockpit is identical to the pressure in the cabin. It is just one tube.

So it is a very valid question why the pilots did not feel the same symptoms.

I have seen some criticism from pilots on the layout of the pack systems on the 737. But if they forgot to switch it on, they would have noticed just like the passengers, but they also would have had some alarms.

The pax oxygen mask auto-deploy at 14.000 feet if the cabin isn’t properly pressurised. Whereas nobody will die at 14.000 feet it is distinctly uncomfortable.

We will need to see what the report says. My money is not so much on the pilots leaving the system off, but the system developing faults during the climb. Maybe with some incorrect operations of the system that caused a rapid pressure change.

We will see once the report is published.

A couple of years I was on a JetAirways plane going from Delhi to Mumbai and the plane had problems with the cabin pressure as well. It descended and returned to Delhi. I wrote about that incident on some other thread. I was not impressed by the way the cockpit and cabin crew handled the incident in terms of communication.

Jeroen

[SCORPION]

Originally Posted by Jeroen

I am not that familiar with the 737, but one thing is for sure, the pressure int he cockpit is identical to the pressure in the cabin. It is just one tube.

So it is a very valid question why the pilots did not feel the same symptoms.

Thanks. Makes me doubt if this was due to pilot error. Must be due to a serious technical issue which was overlooked. Its easier to blame individual pilots rather than blaming the system which results in such incidents. These days, with airlines operating multiple routes with limited number of aircrafts, I wonder how much time is actually spent on proper maintenance.

[Rahul Bhalgat]

Originally Posted by SCORPION

To the experts, is there a separate bleed air for maintaining the pressure inside the cockpit?

Originally Posted by Jeroen

I have seen some criticism from pilots on the layout of the pack systems on the 737. But if they forgot to switch it on, they would have noticed just like the passengers, but they also would have had some alarms.

The pax oxygen mask auto-deploy at 14.000 feet if the cabin isn’t properly pressurised. Whereas nobody will die at 14.000 feet it is distinctly uncomfortable.

We will need to see what the report says. My money is not so much on the pilots leaving the system off, but the system developing faults during the climb. Maybe with some incorrect operations of the system that caused a rapid pressure change.

As Jeron said, there is no separate pressurization for the 737 cockpit. The pilots must have noticed it with the same symptoms plus a warning in the cockpit and subsequently they would have acted. The pilots do have separate oxygen supply that can last longer. Before the first flight of the day, they are supposed to check the proper flow of this oxygen without fluctuations. Fluctuations could indicate interruption in the flow passage.

If there was a rapid change of pressure due to system fault, the passengers too would have noticed it and the same would have reflected in their narrations. Let us wait and see what the investigation reveals.

Originally Posted by SCORPION

Thanks. Makes me doubt if this was due to pilot error. Must be due to a serious technical issue which was overlooked. Its easier to blame individual pilots rather than blaming the system which results in such incidents. These days, with airlines operating multiple routes with limited number of aircrafts, I wonder how much time is actually spent on proper maintenance.

Possible. We will know once the investigation is completed.

[tsk1979]

It could have been much worse
https://en.wikipedia.org/wiki/Helios_Airways_Flight_522

All 121 passengers died when pilots lost consciousness due to lack of air pressure at 30,000 feet

[Rahul Bhalgat]

Originally Posted by SCORPION

Must be due to a serious technical issue which was overlooked. Its easier to blame individual pilots rather than blaming the system which results in such incidents.

It has been confirmed that it was not due to a technical snag. BBC News reported that:

Lalit Gupta, a senior official of India's aviation regulator, the Directorate General of Civil Aviation (DGCA), told the Hindustan Times newspaper that the crew had forgotten to select a switch to maintain cabin pressure.

[SCORPION]

Originally Posted by Rahul Bhalgat

It has been confirmed that it was not due to a technical snag. BBC News reported that:

Then it was a miracle indeed that the pilots remained unaffected and were able to land the aircraft safely.