I agree that in web fora there is always a lot of point-scoring, especially when contributors are keen to display their impeccable PC credentials. However there do appear to be a couple of real pilots on this thread, who can contribute useful information.

I just hope this doesn’t turn out to be another case of an Airbus out-thinking humans but getting it wrong, as happened with AF447.

So the Helios accident hasn’t led to a system to warn pillows of slow depressurisation and the Air France accident hasn’t yet let to longer lasting and better beacons fitted to flight recorders?

So the Helios accident hasn’t led to a system to warn pillows of slow depressurisation

Almost certainly it has. The industry is very good at learning from these mistakes. It might not be in the form of a retrofit warning light, but it would certainly come in the form of training and SOP updates. If XYZ happens then make sure you check DEF as well as ABC.

The first thing my wife did when she got home yesterday was review the update that was issued recently in relation to the A320 on what you need to do if the plane, for some unexplained reason, suddenly starts to descend; as she put it, just a glitch in the system but one not resolved by simply pulling back on the control stick. You have to switch off two other systems or something first beore the plane will respond.

Are you thinking of Helios 522?

Just read about that. Grim. Also read the Air France story several times along with a few others and one thing keeps standing out. It’s the fact that the pilots can misinterpret the warning signals. With all the sophisticated technology available, how is this possible? Maybe it’s my luddite tendencies, but can’t they design the systems to ensure there’s no ambiguity?

Why do pilots ignore their senses and believe their instruments? Have you seen the effect a Sat Nav can have on a driver. We are quite used to being deceived by our senses and are more ready to question those than the output of a machine. And in most cases the machine may be right, but occasionally it’s our senses that are right and the machine that is wrong.

Why do pilots ignore their senses and believe their instruments?

Because human senses aren’t very good at discerning flight parameters (eg gaining/losing height or angles) so when it’s dark or the weather’s bad and they have no visual indicators, you can’t tell what’s happening though senses – just like you can be in a plane not paying attention and then look out of a window and realise that you’re banking fairly sharply.

I just hope this doesn’t turn out to be another case of an Airbus out-thinking humans but getting it wrong, as happened with AF447.

That’s not what happened. They had a sensor issue and misinterpreted what was happening and responded contrary to their training (the co-pilot was fully pulling back almost the whole time believing incorrectly for that circumstance that the plane would not allow a stall)

Why do pilots ignore their senses and believe their instruments?

It will be interesting to see what the other pilots have to say on this, but the one I live with just responded by saying ‘because the instrument is far more likely to be right’. She also explained how when gaining her PPL she had it drummed into her that, in a small plane, it’s not uncommon for your senses to become confused in thick cloud and that you have to trust your instruments and fly on what they are telling you.

This is an interesting read:

Spatial Disorientation

It’s easy to see how the brain can become confused: in a very small way it happens when I stall my car, which has all kinds of annoying interlocks and won’t start until you’ve got the seatbelt on, the gearbox in neutral and the clutch disengaged. When it stalls, trying to get back into the mental sequence and get it re-started can be annoyingly difficult.

That’s exactly the point I was making geetee, 99% of the time the machine is right. What every flight deck needs is a TJ to argue that black is white. A pain in the arse most of the time but just occasionally a voice of reason.

Do you trust your instincts when approaching a speed camera or the speedo on your dash? Your instinct is normally to trust your speedo, but what if it’s wrong?

Two main factors for humans are an acceleration force and a visual point of reference. Other things like noise etc are also important.

Going back to the speedo in a car you will generally have a good source of visual reference and a good perception of speed when driving. So if your speedo is telling you that you are doing 30 but your eyes (and probably engine revs, suspension vibrations etc) are telling you that you are doing 60mph then you know that there is something wrong. If you go from an old car to a modern new big executive cruiser you can actually be quite confused and it is very easy to speed as your senses are not telling you the usual story.

When you are in a big plane acceleration changes can be very slow and gradual and in a plane you are in 3D space so acceleration can mask direction of travel – eg a banked turn will exert a G loading that can mask the gravitation direction. You also have very little to go on in visual point of reference and again we are used to travelling in 2 dimension when on the ground.

A good example is rapid pitch or altitude changes due to turbulence are very easy to detect. But slow sinusoidal changes are not and you can end up with massive variation in altitude that goes unnoticed by those on board, including the pilots.

Another problem is angle of attack and pitch angle are not the same. Angle of attack is the angle at which the air is hitting the wings. If you are travelling perfectly forwards at constant altitude then yes they are the same, if you are falling as well as travelling forwards then the angle of attack is greater as the wing is now seeing air approach from a different angle to the horizon. I remember someone claiming that the artificial horizon is the same as an angle of attack indicator. It is not unless in true level flight (and ignoring the set angle of the wings etc to keep it simple).

Not going to speculate on any crashes or causes further as it just makes people get shirty so just pointing out some examples of where humans AND instruments can be problematic.

The question is do you trust instruments or your senses?

Okay, there’s clearly some misunderstanding by some:

The instruments will let you down far less than your senses/seat of the pants/whatever. Trust them. Your performance instruments (Speed/height/vertical speed) will be cross checked against your attitude reference to confirm all is as it should be. That’s what they didn’t do on AF447 and as a result applied inappropriate side stick inputs worsening the situation.

Yes, instruments fail, and yes, the seat of the pants is one small part of building up the overall picture, but the reason why modern airliners have duplicated and triplicated displays is they are your primary source of attitude reference. If you’ve got a good external horizon, that can form part of your data set to achieve situational awareness, but it won’t be how you accurately set the attitude; that will be done using your primary flight display.

Civilian pilots don’t wear masks all the time because it’s not practical. Most military heavy pilots don’t even wear helmets, however if flying low level or in tactical environments they do.

Fast jet pilots do as it forms an integral part of their survival system should they need to abandon the aircraft.

As far as this awful accident, who knows what happened? There will be experts analysing that data asap and those highly trained people will produce the required reports so the rest of us can learn from it. RIP.

Spatial Disorientation- Thats what killed John F. Kennedy (Jnr)

The first thing my wife did when she got home yesterday was review the update that was issued recently in relation to the A320 on what you need to do if the plane, for some unexplained reason, suddenly starts to descend; as she put it, just a glitch in the system but one not resolved by simply pulling back on the control stick. You have to switch off two other systems or something first beore the plane will respond.

It scares me that such a glitch exists in the first place, and is reliant on a human knowing/having read an update to resolve it….

As far as this awful accident, who knows what happened? There will be experts analysing that data asap and those highly trained people will produce the required reports so the rest of us can learn from it. RIP.

Rumors on PPrune that it was a windshield blowout in the cockpit….I’d like to point out that they are rumors.

Anyway, just read a study that the average time for pilots to put on masks having been given decent decompression training is about 6-7 seconds, 14 seconds maximum, whilst the average for untrained pilots is 15 seconds. The odds therefore don’t seem exactly brilliant even with two trained pilots in the cockpit in the event of a rapid decompression at FL380.

Do they do military style decompression training where they stick you in a decompression chamber, in the commercial world?

Do they do military style decompression training where they stick you in a decompression chamber, in the commercial world?

Apparently not

Rumors on PPrune that it was a windshield blowout in the cockpit….I’d like to point out that they are rumors.

Not knowing anything about it, you wouldn’t think that would do the pilots a lot of good at that kind of speed and altitude. 🙁

Not knowing anything about it, you wouldn’t think that would do the pilots a lot of good at that kind of speed and altitude

Not a lot, no.

BA Flight 5390

Atchison ordered the cabin crew to not release Lancaster’s body despite the assumption of his death because he knew that releasing the body might cause it to fly into the left engine and cause an engine fire or failure which would cause further problems for Atchison in an already highly stressful environment.

He flippin well earned his salary that day!

The Today programme on R4 this morning went over to their “reporter on the scene”, who then spent two minutes describing search helicopters arriving, accompanied by the sound of them doing just that. I switched the radio off. If R4 delivers this sort of trash tabloid style reporting, what hope is there for the rest of the BBC?

Tom_W:

As a long term viewer of PPrune (haven’t posted in years, I hasten to add!), I would take anything said with a pinch of salt. The press often quote from PPrune threads despite them not having any basis in fact…..

Best wait until the report is released.

GeeTee, decompression not practiced in the civilian world. One of many great attributes the mil training system offers.

I find all these “opinions” distasteful.
There were probably Brits on that plane, their families or friends could end up reading this thread. Can you not find some other way of satisfying your engineering/aeronautical/know-it-all egos?

What’s the view like up there on the high ground?

GeeTee, decompression not practiced in the civilian world. One of many great attributes the mil training system offers.

I find that disgraceful considering the profits airlines have been seeing and the potential for high fatalities. Pretty surprised they don’t provide this when two people (the pilots) are responsible for the lives of hundreds of passengers.

Military pilots are only ever generally responsible for themselves, their crew and maybe a platoon or two of squaddies that they are about to push out the back over a drop zone, yet they find a reason to include decompression training.

More to the point, has he got his oxygen mask on?

interesting thread and discussion, @geetee thanks for the info from your wife

Tom,

It’s all based on magnitudes of risk. Pilots regularly train in the simulator for rapid decompression; the occurrence of rapid decompression events doesn’t justify every airline having access to decompression facilities. The same factors come to play in every aspect of life; it’s not reprehensible nor irresponsible. Your car would be unaffordable if it had all the safety systems required to save your life in all situations for example. There should be, even at the highest cruising levels, enough time to mask up. It will be tight but you do train the muscle memory in the sim.

Rapid decompression and emergency descent is something I re-brief myself about on a regular basis whilst in the cruise.

The more common type is a slow decompression; I’ve experienced that myself over mountainous terrain and at night which wasn’t nice. In my case certain advisories were indicated, which only made sense if there was an insidious cabin pressurisation fault. (I hadn’t noticed any effects of hypoxia at that stage, but the cabin altitude was only about 13000′.) A further climb above 14000 would have set off warnings.

I have recently used a synthetic training facility that replicates a slow decompression without the dangers of being in a hypobric chamber (basically your O2 is turned down) which was very interesting. Cheaper and probably more useful in the commercial world. But still unlikely to be required due to the low incidence of decompression.

All commercial aircraft have systems to alert you to an undesirable cabin altitude, normally this will give you lots of time to mask up and get your descent on. Again this strikes me as good practice not irresponsible.

Your knowledge of military crews is seriously lacking; transport crews can be responsible for hundreds of passengers and any flight over any built up area regardless of civilian/mil transport/FJ/Rotary status carries an equal level of responsibility.

I think you should direct your sense of outrage at the 10,000s of dangerous drivers on the UK roads instead.

Tom_W1987

Military pilots are only ever generally responsible for themselves, their crew and maybe a platoon or two of squaddies that they are about to push out the back over a drop zone, yet they find a reason to include decompression training

Surely this is for a number of reasons that make flying a military fast jet rather different to a passenger airliner? (like the presence of Ejection seats for a start, which kinda “decompress” the cabin rather explosively if you ever need to use it, and the fact that Military jets fly in close formation, get shot at, and generally contain a lot more cutting edge tech that can let you down etc etc)

Reported that one of the pilots was locked out of the cockpit:

http://wrd.cm/1EGH2Q8

Surely this is for a number of reasons that make flying a military fast jet rather different to a passenger airliner? (like the presence of Ejection seats for a start, which kinda “decompress” the cabin rather explosively if you ever need to use it, and the fact that Military jets fly in close formation, get shot at, and generally contain a lot more cutting edge tech that can let you down etc etc)

I’m pretty sure the heavy pilots do it as well.

I think you should direct your sense of outrage at the 10,000s of dangerous drivers on the UK roads instead.

Car companies are actually trying to rectify that though aren’t they, by introducing self driving cars. Given the profits airlines make, I’m not sure the expensive car analogy holds up. I’m also pretty sure that your average airline pilot is responsible for far more lives each year and over the course of their career than a military pilot.

I’ll tell you what, when driverless cars have any kind of footprint in terms of sales anywhere in the world, then you can start to make that argument. Until then, you are still far more likely to die from cars than any other form of transport.

It seems like allowing a single pilot to be alone in the cockpit with the post 9-11 reinforced doors is a bad idea. Though the chances of something bad (heart attack, seizure, etc.) happening are miniscule, the result would always be catastrophic.

The fix is easy; when a pilot leaves the cockpit, a flight attendant goes into the cockpit until the pilot returns. While the flight attendant couldn’t fly the plane, they could open the door and let the other pilot who can back in!

Edit – another lockout earlier this year http://www.cnn.com/2015/01/30/travel/feat-delta-captain-lockout/

Yup BBC reporting either Pilot or 1st officer locked out of cockpit with audio supporting timid then more frantic efforts to get back in…

Yikes.

Given the profits airlines make, I’m not sure the expensive car analogy holds up

Second time you’ve said that, but most airlines make either very meagre profits, or spectacular losses these days! They’re doing alright right now with low oil prices, but that’s very volatile.

Fact is that decompression is a very rare occurrence in civil aviation. You can’t conceivably train for absolutely every potential incident.

How much per pilot per course, the one day courses can’t be much more expensive than say….the oil industry having to train for helicopter ditching. Don’t buy it really, Easyjet have been making consistent profits since 2000 and last year put away 450m after tax.

Tom

On many flights profit is down to a handful of seats. Lo-co airlines have higher margins, but their crews still have to pass the regulatory training.

Your comments regarding responsibility highlight you don’t know much about aviation in general; there’s clearly no point in me elaborating as you obviously don’t get it. I have done both (mil and airline flying) and I treat both types of flying with the same respect. The ground will kill you and those with you whatever your uniform. The law won’t discriminate between uniforms either.

I’m sure details will be released soon for those desperate to point blame, Tom, I hope the families get to grieve without intrusion. RIP.

I’m interested more than anything Mike, quite happy to listen to you. Hypobaric training cost about $100 per pilot back in the 90s according to an ex A-10 pilot I know…..

I am sure that on a previous thread a STW ‘expert’ said that there is a way in to the flight deck that only crew know?

FunkyDunc – Member
I am sure that on a previous thread a STW ‘expert’ said that there is a way in to the flight deck that only crew know?

Also alluded to on R4 this morning in a “ways we don’t talk about on air” kind of way. What’s surprising is how this stuff has got out, given that the same guy said there are only three rooms in Europe in which these voice recorders can be listened to.

Getting conflicting info about that…. supposedly, if the deadbolt has been put in place there is no way you can get back in. The easiest solution would be to just have two crew members on the flight deck at all times – anyone care to explain to me why no one has thought that wrapping pilots in an armored box might lead to it’s own set of problems? Or is there actually a way for pilots to get back in safely?

Do they have an image recording ‘black box’ within the cockpit as well as the voice recording one?

“The fix is easy; when a pilot leaves the cockpit, a flight attendant goes into the cockpit until the pilot returns. While the flight attendant couldn’t fly the plane, they could open the door and let the other pilot who can back in”

TBH I thought some airlines do that, but that os down to each company’s operation manual.

Yes the A320 has a electric keypad on the outside cockpit door to unlock it, (and having been locked out of the cockpit on checks having to make a phone call for the code is bit embarrassing) to be able to get in, but it can be over ridden (locking the door) from in the cockpit, as they also have cameras above the door and galley area, so the pilots can check for people hiding or holding crew hostage.