Things I always wanted to know as a passenger

[Peter92456]

I am a regular passenger and always wondered about the following:

1. What does the announcement " Doors to manual and cross check" mean?

2. You use wing flaps land the aircraft, why not use them for take off?

3. The pre-flight briefing makes great play on life jackets when landing on water. But what are the chances of survival of the aircraft on water when those engines under the wing dig into the water and disturb the aircarft attitude.

Would love to know
Thank you

[Caudillo]

Peter, #1 I don't know, but I'd assumed it's to do with disarming the slides before the doors open, in order that they don't do their thing when they're not needed.

Regarding #2 - we do, except they're deflected much less on take off than on landing. Have a good look next time and you'll notice it. The settings for take off are tradeoff between getting off the runway ASAP and climb gradient. More flaps on takeoff equals less runway used but a shallower climb. For landing, the flaps are there to provide added drag.

As for #3 I understand that aircraft have successfully managed it, but in fairness I'd be reaching for the duty free rather than a lifejacket. We have no meaningful training in getting the thing onto water in one piece. Rather than worry about lifejackets, I'd just keep the seatbelt on, you're much more likely to cop an injury from turbulence.

[toolowtoofast]

*disclaimer*i'm not a hostie*

'doors manual' is on landing to ensure the slides don't deploy when they are opened (especially if opened from the outside as it is not possible to see if they are armed or not - just a big noise and the worlds biggest inflatable doll appearing in your airbridge!) i presume 'cross check' is to double check they are disarmed

flaps ARE used for take off - there are 'take off' and 'landing' flap settings.

putting your life jacket on is a good distractor from thinking about how much it's going to hurt when you're going to hit the water at 500mph.

[Hotel Mode]

1 It means disarm the slides so they wont go off when the doors open. Then the crew member at the opposite door must check this has been done.

2. We do, just normally not as much. The last bit we use for landing creates a lot more drag so whilst the few extra knots we can slow down is good for landing it would actually impair take off. The less flap the less drag, you'll need more runway but will climb faster.

3. Many pax survived the Ethiopian 767 ditching, many of those that died survived the impact but inflated their lifejackets before getting out hindering their escape. There have also been several aircraft off ends/sides of runways into water in the past.

[PAXboy]

Cross checking that an emergency slide HAS been selected to manual is vital as the cost of 'blowing the slide' is very high. Not least as the aircraft will be off duty until it gets a new one fitted. Even if the a/c is at a maintenance base, that could take many hours.

The 'flap' is an movable extension to the wing. When an a/c is going slowly, if the wing is larger it makes it improves all sorts of things. Once the machine is going faster, the flaps are retracted as they are not needed. As you have heard, they also add 'drag'. This is in the very last part of the descent.

The main occasions when water and survival work out is a low speed event. This would normally be where there is a stretch of water in close proximity to the airfield. So that, if the departure fails (very badly!!) then you will be entering the water at a relatively slow speed and, as mentioned above, if the machine fails the landing and overruns the end of the field and enters the water. If a machine enters/touches water at high speed, the result will be the same as if it did so on hard land.

[Peter92456]

Thank you everyone for your replies
You have answered my questions.
I appreciated your humour
Thanks
Peter

[Hartington]

I only flew "Go" one round trip but they had 3 crew on a 737. It slightly amused me when they went through the "cross check" bit. There was one crew member at the front who simply set both doors and then cross checked him/herself.

Given that I suspect most locos have the same cc staffing the cross check bit seems slightly superfluous.

[Avman]

Given that I suspect most locos have the same cc staffing the cross check bit seems slightly superfluous.
The cross check is with regard to the CC arming/disarming the rear doors.

[kiwi chick]

As for #3 I understand that aircraft have successfully managed it, but in fairness I'd be reaching for the duty free rather than a lifejacket.

putting your life jacket on is a good distractor from thinking about how much it's going to hurt when you're going to hit the water at 500mph.

Hahahaha!!!! :D :D :D

[airbus777]

If the doors areopened from the outside and the doors are still in automatic the slide will not deploy.They will only deploy if opened from the inside of the aircraft when still in automatic.

[Rainboe]

airbus- you are incorrect. The B737 has a manual selection of arming and disarming the doors. You open an armed 737 door from the inside or the outside and you will get a surprise!

There is always someone who knows little and criticises!- 'cross check' is a valid call even on a 3 crew aeroplane. Why couldn't you just ask, rather than state a critical opinion on the basis of little knowledge, Hartington?

When I joined BOAC, I received regular training and demonstration films of experimental ditching of a large VC10 model in a water tank, together with extensive instruction of wave formations and how to handle ditching with regard to wave direction and wind effect. Done the right way, very little damage will occur- the engines are designed to come off easily and pass under the wing for aircraft like 747. It is vital to be slow and to avoid a wingtip digging-in as in the Ethiopian 767 which ditched wing down. Planes will float like corks, especially if the wing is intact and reasonably empty of fuel. On the top of wings is a nice ring to take a line from the cabin and provide a base from which to get people onto the wing and launch liferafts. It will work, and with little structural damage. It has several times. There was even a Japan Airlines DC8 that ditched into Tokyo Bay. It was recovered and repaired and actually flew again as a passenger plane.

[Mark1234]

Last trip I sat on a 738 in row 1:

Doors to automatic: Take the little bar off it's hanger on the door and clip it to the floor. Put the little orange tape across the window
Doors to manual: unclip from floor and clip into hanger on door, remove orange tape.

So I'm picking it wouldn't matter which side the door was opened from, and that the sole purpose of the orange tape is to indicate to person outside NOT to pull the handle.

The question I've always wanted to ask, but never dared (for fear of being escorted from the cabin in handcuffs and sent straight to a well known bay, never to return...)

Is there some kind of interlock stopping someone pulling the door in the cruise? It would seem deceptively easy for some nutjob to head for the toilet, then yank the handle at the last minute! However, if there's an interlock, who makes sure it's disengaged when it all goes wrong (prior to the big thump) - would seem flight crew would be more preoccupied attempting to avoid big thump.

Actually, I think I may have just answered my own question: is it just a case of the internal pressurisation being enough to hold the door against the seal harder than any person can pull?

[toolowtoofast]

just what i was thinking - apart from a slight resistance, the girt bar in a 73 is really hard to detect if it's still hooked into the floor.

the dangers of assumption when jumping types.

and yes, there is a pressure switch that stops the door handle from being opened if there is more px inside the cabin than out, however, some doors (most pax doors on big jets) are plug type, and couldn't be opened against the pressure anyway - they have a flap at top and bottom to allow them to be fitted out the hole. the main cargo door on boeings though is not a plug door - is held closed by big hooks.

[Driver_Once_More]

that's pne of my questions answered as well, thank you

[PAXboy]

If I recall correctly, the offset in PSI on the door being pushed OUTWARDS from the cabin and ONTO it's seating is so high that you would need to pull in excess of 200lbs towards you. Maybe more?

Certainly, any time that you hear about pax 'wrestling for the handle' the newspaper reporting will be wrong! It is true that pax nearby will become agitated but, afterwards, the crew will explain it to the pax.

[Maude Charlee]

I'm sure if you worked it out (I can't be arsed), but with a pressure differential of up to 8 lbs/sq in, on a bloody great big bit of pax door, that's a whole lot more than 200 lbs of force required!

[Rainboe]

Calculate- door about 78 inches x 36 inches (minimum) x 8 pounds Sq. in= 22,464 pounds pressure on that door, holding it against the stops. I would quite happily stand watching as the worlds most strongest man tried to wrestle with that. You don't need interlocks, and indeed most doors don't have them. The plug door has to open inwards first, so you need to defeat that pressure, before the door can be open- not just slide it past the stops to open. The handle mechanism isn't anywhere near strong enough. Makes for good scenes in movies though.

[tyl3r]

4. Cabin lights dimmed for t/o or landing :confused:

[FWOF]

I beleive the lights are dimmed on t/o and landing, when it is dark/getting dark, is so that if you DID have to leave the a/c in a hurry your eyes are already adjusted to the dark outside. Leaving a brightly lit area into a dark one, you know that it takes a few seconds for your eyes to adjust.

[airbus777]

sorry rainboe,am at LHR and we dont have the 737!

[frequentflyer2]

'When I joined BOAC, I received regular training and demonstration films of experimental ditching of a large VC10 model in a water tank, together with extensive instruction of wave formations and how to handle ditching with regard to wave direction and wind effect. Done the right way, very little damage will occur- the engines are designed to come off easily and pass under the wing for aircraft like 747. It is vital to be slow and to avoid a wingtip digging-in as in the Ethiopian 767 which ditched wing down. Planes will float like corks, especially if the wing is intact and reasonably empty of fuel. On the top of wings is a nice ring to take a line from the cabin and provide a base from which to get people onto the wing and launch liferafts. It will work, and with little structural damage. It has several times. There was even a Japan Airlines DC8 that ditched into Tokyo Bay. It was recovered and repaired and actually flew again as a passenger plane.'

I can understand the theory of egress from a ditched airliner such as a Boeing 747 or VC10 with the wings acting as a buoyancy aid.
But what happens if, for example, you're approaching BHD on a Dash 8 or a BAe 146 and there's no option other than a controlled ditching into Belfast Lough?
The wings on these aircraft are above the doors and windows so presumably means of egress would be beneath the surface of the not so clean water - or would these aircraft come to rest in an attitude which would keep at least one door above the surface?

[Ozzy]

I like Billy Connolly's advice to the pilot when considering ditching....."aim for a puddle":E

Ozzy

[PAXboy]

The 146 is designed to float slightly nose up. The rear doors are then (ahem) unavailable and all exit is via the front two doors. Cannot say for the Dash as I have not been on it (until next month) but the 146 and I are old friends.

[Rwy in Sight]

So if for some reason the front part of an 146 is deformed in case of a ditching all hope is lost..


I am happy I am flying on an ATR tomorrow.

Rwy in Sight

[Hotel Mode]

So if for some reason the front part of an 146 is deformed in case of a ditching all hope is lost..

I am happy I am flying on an ATR tomorrow.


Having flown both and seen both built can i suggest that in event of any accident you'd be better off in the one built for ruggedness by engineers not the one built for cheapness by accountants.

[Rwy in Sight]

I am not sure which one is which. But I rather avoid an aircraft with engines rather than hair dryers.

Btw. When on a full ATR (regardless if it is a 42 or 72), I feel that an evacuation within 90 second and half the doors in-op is not possible. I know it is an irrational fear but it resides with me given that I don't feel likewise with other aircraft. I know that the ATR is certified and all but still...

Rwy in Sight

[nebpor]

Rwy, the 146 is I believe known as one of the sturdiest aircraft flying - it was designed for short, hard landings, etc .... there is no reason to avoid them in the slightest.

Plus, it has 4 engines - plenty of resilience :ok:

[radeng]

"Doors to manual and cross check" means that the champagne will be coming round shortly!

[frequentflyer2]

'The 146 is designed to float slightly nose up. The rear doors are then (ahem) unavailable and all exit is via the front two doors. Cannot say for the Dash as I have not been on it (until next month) but the 146 and I are old friends'.

Alright then. Here's a scenario. Say the pilot executes a perfect ditching and the good old 'whisperjet' is bobbing around providing entertainment for the patrons of Cultra Yacht Club with its rear doors partially (or wholly submerged) but front doors clear of the water.
I'm a non swimmer but I've prepared for ditching by putting on my lifejacket which I know I mustn't inflate inside the aircraft.
I'm also hoping my whistle will be loud enough and my flashing light bright enough to attract the attention of the wealthy North Down boat owners who by this stage are doubtless heading to the scene.
Now I'm going to ask a serious question which I hope someone can answer - what happens next?
Everyone will want off that aircraft before it slides beneath the Belfast Lough shipping channel. Ergo everyone will head for the exits. But no matter how orderly this is, the distribution of weight inside the 146 will change presumably affecting its attitude in the water.
So how precisely do cabin crew direct passengers to evacuate the aircraft bearing in mind the more people who move towards the front, the closer to the waterline the exits will become.
Meanwhile, presumably, the tail will rise bringing the rear doors clear of the surface.
Can any member of cabin or flight deck crew tell me precisely what they have been told to do in this situation?

[TightSlot]

The situation is the same with exits in a ditching for some 737 types i.e. fwd/o'wing exits only.

I assume that the problem resolves itself since although people are moving forward, they are also getting off - the aircraft is also getting lighter by several tonnes at the same time - this is a guess, so I may be incorrect.

The thing with ditching is, you have to have a plan. I can see that it's not a very promising plan in some ways, and certainly fraught with danger - it is, however, much easier to pick holes in the existing plans than it is to come up with an alternative.

[Rainboe]

frequent flyer- you are obviously in a very picky mood! Try this:
Not everybody can cluster around the front exit. It's very limited (see what happens when the engines shut off- you can't move until the door opens). So the aeroplane is not going to tip nose down in the water. As people exit, more will take their place. So nothing happens- the balance remains the same. It will work. Done correctly, the fuselage will remain intact and the aeroplane will float happily for as long as required. Even the wings should remain intact providing fantastic buoyancy.

May I suggest prolonging this discussion is a waste of time? Unless you have any positive contributions or ideas?

[frequentflyer2]

Alright - the first part of my post referring to Cultra Yacht Club and wealthy North Down boat owners was perhaps an innapropriate Friday night attempt at humour. But the question was a serious one and not intended to be picky. The title of this forum is Passengers and SLF. I fly fairly often and can't swim. In the event (albeit very unlikely) of an aircraft on which I'm travelling having to 'put down on water' I would be totally reliant on my lifejacket and the instructions of the cabin crew. I've often thought about this while taking off from or approaching BHD over Belfast Lough. There must also be the potential for the ditching in Lough Neagh of an aircraft either departing from or arriving at BFS. We are frequently told the most likely scenario for an aircraft going 'in the drink' is when departing from or arriving at an airport close to an expanse of water. I simply wanted any advice the professionals could give me on how this piece of SLF could give himself the best possible chance of surviving such an incident.

[Donkey497]

Just one minor fly in the ointment with ditching, which seems to be gleefully ignored or glossed over, especially in our climate is hypothermia.:uhoh:

Just how long is the survival time for an exposed body in the North Atlantic, Irish Sea or North Sea, even when equipped with a life jacket. From (very dusty) memory, in summer it might stretch to a couple of hours, but in this season of the year it comes down to a few minutes, so I guess that your whistle and light are just there to keep you entertained as you freeze to death......
:sad:

[lexxity]

North Atlantic I believe is 30 mins or less. It is a very cold place even in summer.

[perkin]

You might be lucky to manage a couple of hours in a survival suit, but North Sea in winter most people are looking at minutes...assuming you survive the ditching...

[frequentflyer2]

When I posted my original query I was thinking about a mishap over Belfast Lough while approaching or departing BHD. However, bearing these survival times in mind perhaps my positive contribution - as suggested by Rainboe - should be to suggest the same provision of liferafts on short domestic flights as on long transoceanic flights. I'm sure RFD at Dunmurry could provide something nifty for the 146/Embraer 145/Dash 8-400 in the same way as they provide liferafts for Boeing 747's etc. If an aircraft ever did end up bobbing around on the Lough - it's highly unlikely but not totally impossible - and a lack of liferafts was found by an inquiry to have led to the deaths of people who might otherwise have survived there would be a public outcry. Were there any liferafts on the ATR which ditched off Sicily? If there weren't would their availability have led to a larger number of survivors?

[TightSlot]

Liferafts are both heavy and bulky, and so loading them on domestic flights would have immediate cost and profit implications. The thing about safety is that it is always a compromise between the likelihood of there being a quantifiable safety benefit and the costs. We may be uncomfortable with this, but it is essentially the same process as is involved with life insurance. The safest aircraft that could be built would never leave the ground.

I don't think that there is a body of evidence that the provision of life rafts would substantially enhance survivability in short-haul ditching (If I'm wrong, apologies and please advise). There have been numerous accidents on both take-off and landing where the aircraft has finished up unexpectedly in water, of varying depth and temperature (e.g USAir 737-400 NN461US at LaGuardia (http://aviation-safety.net/database/record.php?id=19890920-0)) - The best advice for all passengers IMO remains thus - Know where your nearest exit is, know the brace position and know how to fit a lifejacket and when to inflate it. These three points, combined with a single-minded determination to get out will substantially improve your chances of surviving most survivable accidents/incidents.

The hypothermia issue is of course, quite correct: It is also true that ditching an aircraft is an inherently dangerous procedure: Surely, the point is that, while recognizing the above, there still has to be a workable procedure for an evac into water: The odds may be against survival, but we still have to have a plan that is more robust than "Sorry, you've had your chips!!!"

[Rainboe]

Liferafts are extremely heavy, and in a planned scenario must be removed from their stowage before ditching. In which case they are useable and can be launched from the door....bearing in mind the aeroplane is, in this story, intact. But why would you want to leave it? If the aeroplane breaks up, they are not useable anyway just when the survivors would be flailing around in the water totally unable to find them, so they are absolutely useless when you most need them. However, shorthaul aircraft in a planned scenario would not chose ditching as opposed to crash landing anyway, so not needed anyway. Therefore there is no case for shorthaul aircraft to go through the expense of permanently equipping. On our ETOPs 737, we have 3 liferafts for 138 max headds, at a weight of 180kgs. They are big and bulky and take up valuable overhead bin space, and at 60kgs each take a lot of manoeuvring and strength to move.

[6chimes]

Cabin lights dimmed for t/o or landing

To add to the earlier response.

You need to get to an exit before you can get out, hence the emergency lighting that includes the aisles, ceilings and exit signs. Yours eyes need to adjust to the low level of light produced by the emergency lighting, which takes longer than than the time you may have to evacuate.

North Atlantic I believe is 30 mins or less. It is a very cold place even in summer.

The survival times in the sea vary vastly and it is just down to wether or not you are wearing a lifejacket. In the Atlantic around our coast without a lifejacket you could be looking at 9 min, yet with a jacket it could be over an hour. Most people who can swim well believe that they stand a better chance of survival in this scenario but in fact it is they who will die first as they use their arms and legs which sends nice warm blood into areas of the body where veins and arteries are close to the water and thus cools much quicker and hypothermia sets in earlier. But even before you have got into the water there is a bigger threat to your survival and that is cold shock. When you leap into water that is cold you involuntarily gasp, if your lifejacket does not have sufficient slack in it to allow for your chest to expand to its maximum then you will hyperventilate. You will have no control over it and hence no control of the large amounts of sea water you will be sucking into your lungs. Nice thought.......:{


6

[10secondsurvey]

Tightslot,

You say, 'know the brace position'. What use is that if the seats are so close together that you cannot adopt said position. Personally, I've always been amazed that airlines get away with it. The brace position was developed from research into survivability, and based upon experience of injuries experienced when aircraft crash (including kegworth), but on many airlines it cannot be done, as the seat in front is too close.

I'm not trying to be picky, its just that I know you work in the industry, and I'm not sure how they square it.

[10secondsurvey]

Another quick point. I was recently on a flight in Europe, and the ground level lighting strip showing where the overwing exits are, was out of alignment with the exit rows. In a dark smoke filled cabin, I guess many people would die trying to get out of a regular window by following the floor lighting. I have to say, it's the first time I had seen such a problem.

This, for the record, was on a major European carrier.

[WdW]

I am a navigation enthusiast, and take my Garmin handheld GPS receiver along on most trips. Usually stowed in cabin luggage, but have on occasion used (or tried to use) it during the flight. On some occasions the cabin crew got permission from the cockpit without problems, on other occasions the response was a very definite "NO."

I do accept that whatever the PIC says goes - so no worries - but am curious as to WHY someone would not allow the use of a handheld GPS receiver in the back. It is a after all a RECEIVER - or does it actually transmit anything that could interfere with instrumentation?

[TightSlot]

10SS

I had a trawl through Google for safety card images but couldn't find one to make the point, so you'll have to take me on trust here for the time being.

In the UK, at least, the brace position has to be achievable for the seat pitch/config - Next time you fly, please double-check the position shown. As far as I am aware, it (generically) features the pap leaning forward, resting the forehead/forearm on the back of the seat in front with forearms either side of the head, hands overlapping (i.e. not fingers interlocked) behind the head: Legs should be bent at the knee, with the ankles slightly behind the knees and feet flat on the floor. There is a different position when infants are on laps.

I believe (honestly) that this position is achievable for pax in 28" seat pitch, and that it offers a degree of protection, certainly from severe head-strike injury. The position of the feet and lower leg was (I believe) modified after Kegworth.

[perkin]

Its more to do with resting your head against the first thing it would hit on impact if you were just sitting normally in your seat, with the aim of reducing the severity of injury. So either the seat back infront of you, or your knees essentially...the latter being shown on safety cards.

[PAXboy]

With regards to drowning, a small point that will be of no comfort(!) when a person drowns, they tend not to get too much water into their lungs as inhaling water triggers the airway to seal shut - a reflex called a laryngospasm. I read that, most who drown actually suffocate.

WdW Welcome to the forum, this subject has been discussed here and the Search facility should bring information about electronic devices on board. The short answer is Yes, the device does emit radio frequency (RF), albeit a small amount. The reason is to do with micro-processors. The concern is that the interference from the device is unknown and therefore, the safest is to keep it switched off. As I say, there are a number of threads that have contributions from engineers.

[WdW]

WdW Welcome to the forum, this subject has been discussed here and the Search facility should bring information about electronic devices on board. The short answer is Yes,

Thanks for the welcome, PAXboy. Have since found the (vast) archive, and am busy sifting through that ...

Thanks again.

[PAXboy]

:)
Just noticed that you are in Richards Bay, ZA. I remember well my flight into RCB, even though it was nearly 23 years ago, partly because it was an 8-seater something in atrocious weather. The most amusing part was the road leading away from the terminal (a tiny building) and that the tar finished after about 500m and then it was dust track as usual. High tech gave way to Afrika! Go Well.

[108.9]

Another question if I may?!

Why when taxing to the runway for takeoff are the cabin crew allowed to walk about the cabin, but after landing when taxing to the gate they are not??

[WdW]

I remember well my flight into RCB, even though it was nearly 23 years ago, partly because it was an 8-seater something in atrocious weather. The most amusing part was the road leading away from the terminal (a tiny building) and that the tar finished after about 500m and then it was dust track as usual. High tech gave way to Afrika!


The place has grown considerably - I have lived here since early 70's. Residential areas now go AROUND that airport. And yes, I also remember some dubious operators from here.

On one occasion, a 06h00 take-off with "Metavia Airlines", headed for JNB. A rustbucket of note, 17-seater I think. No idea of make or model.

Just as were going into the low cloud, a passenger actually managed to OPEN THE EMERGENCY EXIT. His first time flying, and he wanted to "open a window". I kid you not. Fortunately not a pressurised cabin, but still frightening. We turned around and headed back to RCB. The upper part of the door was found in the bush some weeks later.

This must have been early to mid 90's. I have since searched all over the net for a record of the event, but simply cannot find any.

Can someone translate THIS page? It pretty much looks the same as the aircraft we were in (a LET 410 UVP-E?) - and it may just be that the author is telling the story.

http://www.avijacijabezgranica.com/forum/viewtopic.php?t=3214

[6chimes]

Why when taxing to the runway for takeoff are the cabin crew allowed to walk about the cabin, but after landing when taxing to the gate they are not??

As with any aspect of commercial aviation a balance has to be struck between safety and service. The crew are permitted to move around the cabin to make sure that we are all safe for take off. These duties should be completed and then the crew should take their seats. There have been many cases of a/c colliding with each other on the ground, which could seriously injure anyone not strapped in. After landing though is different because all the security procedures would/should have been completed in the air.

Hope that helps.

6

[easy1]

If you find yourself in situation number 3, follow these rules,
1) Stick your head between your legs
2) Kiss your arse goodbye
3) Hope your flying 1st class, what a **** way to die on RYAN AIR rat class!!:E

[easy1]

YOU SEE, EVEN GB/BA/soon to become easyjet GET IT WRONG!!!!!!!!!:D

[PAXboy]

easy1 You might want to stay in coach (Y). Aircraft tend to travel in the direction of the pointy end of the machine. This means that the pax in 1st are also 2nd in line for meeting the unmovable object (after the flight crew :sad:). So there is one compensation to being down the back end, you might just walk away and be able to look at the 1st class cabin, also known as, the crumple zone.

[10secondsurvey]

For the record, it wasn't EZY or BA......

[10secondsurvey]

Tightslot,

The Brace position you describe (and I've seen safety cards with it), leaning on the seat in front, whilst upright, is in my mind nonsense inspired by airlines who suddenly realised the 'correct' brace position would not be possible with high density seating. It is not ideal. Previously, the position involved bending over, with elbows to the side, but now it's just lean on the seat in front, whilst upright. And I know changes were advised following kegworth, but I don't think that change ever came about because of new research following kegworth.

No, if you want to adopt a good brace position, make sure you are in business class. With 28 inch pitch (26 inches of legroom), forget it.

The best solution is of course flying backwards (as the forces used to do - maybe they still do it?), and you can do that, if you fly clubworld on BA.

[TightSlot]

is in my mind nonsense inspired by airlines who suddenly realised the 'correct' brace position would not be possible with high density seating

The Brace position for each type of seat/seat pitch is determined and overseen by the CAA - airlines do not have the authority to amend it. The CAA approved Brace position allows for practical use within the high-density seating pitch and configuration which is also determined and overseen by the CAA.

There has never been an economy seat pitch that permitted the upper body to bend fully flat against the thighs without the head coming in contact with the seat in front.

The primary purpose of the Brace position is to minimize head-strike injury, and the existing Brace position for high-density 28" seat pitch does exactly that.

This seems to be the second thread on which we are exchanging contrasting opinions. I have to say that your opinion of both the CAA and the airlines appears to be rather low. Whilst it is true that both display many faults, I believe that you underestimate the level of knowledge on safety matters and depth of study that these organizations employ. Policy on matters such as seat pitch, exit configuration and brace position is determined not on the back of a fag packet by airline marketing people but by accredited experts who have a lifetime of experience in their fields. To assume otherwise might appear naive.

[jamier]

What would happen if you depart and have to ditch in water very soon after takeoff (no time to dump fuel etc) assuming you survive the ditching would the wings not be super heavy with all the fuel they are carrying and mae the aircraft sink alot faster?

[rsuggitt]

Also, if one was a terrorist and had smuggled a device on board and wanted to detonate it at a specific point (eg when the aircraft was smack over a given city centre), the a GPS would pinpoint your position for you, even in IMC.

[Leezyjet]

Calculate- door about 78 inches x 36 inches (minimum) x 8 pounds Sq. in= 22,464 pounds pressure on that door, holding it against the stops. I would quite happily stand watching as the worlds most strongest man tried to wrestle with that. You don't need interlocks, and indeed most doors don't have them. The plug door has to open inwards first, so you need to defeat that pressure, before the door can be open- not just slide it past the stops to open. The handle mechanism isn't anywhere near strong enough. Makes for good scenes in movies though.

I met a flight a few years back where a chap had tried to open the e/exit at about 500ft on final approach on an A321 with the outward opening doors. Tried to find out if it would have opened had he not been wrestled to the floor as the a/c at that point would presumably no longer be pressurised, and the Airbus type doors do not seem to be plug doors like the B737/B747 style doors, but even the Capt and the Engineers were not sure.

Why when taxing to the runway for takeoff are the cabin crew allowed to walk about the cabin, but after landing when taxing to the gate they are not??

I thought it was because on departure, people are not in a rush to get off, however on arrival, where everyone wants to be off ASAP, if the pax see crew walking around they will then assume they can too and begin to get up and get their h/luggage - although in some parts of the world they do this anyway !! :eek:

:\

[SXB]

Why when taxing to the runway for takeoff are the cabin crew allowed to walk about the cabin, but after landing when taxing to the gate they are not??

Sometimes not even the passengers are seated. On Saturday I was on my way to a wedding in Belgrade and saw the most flagrant disregard of the seatbelt sign I've ever seen on an aircraft outside of eastern Europe. As the aircraft taxied to the runway, cabin crew already strapped in, someone got up and went to the toilet, then another, and another. They were all seated a good two or three minutes before the aircraft reached the runway but, according to the drop down screens, at about 1700m into the climb another passenger went and used the toilet and then another, and another. At that point the purser came racing down from the front of the aircraft and quickly seated all of the offenders. I don't know what the attendant at the back of the aircraft was doing through all this but I could hear her telling the offenders, in English, French and German, to sit down but she never got out of her seat.

The chaos continued as we landed in Belgrade, as soon as the wheels hit the ground some of the passengers were out of their seats and retrieving luggage from the overhead lockers.

Clearly the main issue was one of language, a lot of the Serbs on the flight clearly didn't speak English, French or German, plus it was obvious they don't fly that often.

I've seen this happen on other flights to the Balkans and eastern Europe and normally the CC, firstly, point towards the seats and if that doesn't work they stand up and guide the offenders back to their seats.

For info the flight was Swiss LX1416 from Zurich to Belgrade. This flight also broke the record for the most amount of ringing mobile phones as the plane descended into belgrade......

[AviationNE]

When flying into a headwind why does the flight take longer. Aswell as when flying with a tailwind why does it go quicker. I Ask this because ia lways presumed that the aircraft flew at the same airspeed regardless of the flight?

[G-BPED]

As far as I understand, Head/Tail winds affect Ground Speed not the Air Speed of the aircraft.

So, a Head wind will reduce Ground Speed. A Tail Wind will increase the Ground Speed.

This is just my basic comment, I am sure a more knowledgable person will be along to explain in detail.

Regards,

G-BPED

[TightSlot]

It's not so much the immediate effect of the wind (head/tail) on the aircraft as that the entire block of air through which the aircraft is flying has moved in some direction. Think of the aircraft as flying through a cube of air - say 100 miles square: During the time taken to fly through it, the entire cube has shifted, say 5 miles against the direction of travel: Therefore the aircraft has to fly 105 miles through the air, at a constant speed, in order to cover 100 miles across the ground.

I think that's clear - I'm confusing myself now...

:hmm:

[Maude Charlee]

Easier to think of a boat on a river - it goes faster with the current than against it, but at all times is still only going at the same speed through the water.

[fix it]

Tidal Currents, speed over land (SOL) compared to speed through the water (STTW). Its all a lottery out there!!!!!

[Brakes...beer]

Just to correct a misconception from page 1: aeroplanes do not use higher flap settings on landing "to increase drag"; they use those settings to increase lift at low speeds, thereby allowing them to land at lower speeds without stalling. The resulting increase in drag is an unfortunate side-effect which has to be compensated for with increased thrust.

[Mark1234]

Don't you mean the increase in drag is a rather useful effect that enables a steeper approach, and better obstacle clearance, without increasing speed? (at least in the little stuff I fly)

I believe it's also rather beneficial in the big tin to have the engines working a bit against the additional drag as they spool up a disproportinately quicker from a bit of power than they do from flat idle should one need to go around or similar.

[DeRodeKat]

Well, flaps are used both to increase lift at lower speed and to create drag. There are also slats at the leading edge of the wing, which do increase lift at low speeds but without considerable drag. On some aircraft like Fokker-70/100 flaps are normally not used during take off.

[Slasher]

When flying into a headwind why does the flight take longer. As well as when flying with a tailwind why does it go quicker. I Ask this because ia lways presumed that the aircraft flew at the same airspeed regardless of the flight?

Just go outside and pee in the wind in
varius directions for a definitive answer.

[kiwi chick]

Oh, surely, but SURELY that was a wind-up?! :\ :confused:

[Slasher]

Nope its not. But such a investigatery experiment
of discovery might not work well for chicks! :\

[Economics101]

Nope, he was just taking the p*ss.

Sorry, but you asked for that!

[Dushan]

Sometimes not even the passengers are seated. On Saturday I was on my way to a wedding in Belgrade and saw the most flagrant disregard of the seatbelt sign I've ever seen on an aircraft outside of eastern Europe. ...
... This flight also broke the record for the most amount of ringing mobile phones as the plane descended into belgrade......
SXB
seems to me you were smack in the middle of Eastern Europe from the moment you stepped on that palne in Zurich:eek:

[Flapping_Madly]

I can see why planes land either from the east or west at LHR. Headwind i suppose.
But why do planes sometimes land on the south runway and sometimes the North? Do they flip a coin to decide? Do ATC have personal preferences ?
Is it to even out wear and tear on the concrete?

AND why do some planes "overtake" the stream of landing planes and sneak in on the take off runway?
Are they short of fuel?:confused:
Thanks

[llondel]

But why do planes sometimes land on the south runway and sometimes the North? Do they flip a coin to decide? Do ATC have personal preferences ?

This one is all down to politics. There's a longstanding agreement with local residents which effectively means that one runways is used for landings and the other for takeoffs, with a changeover at about 3pm. This means that the locals off the end of each runway only have to listen to aircraft for half the day. It also restricts capacity - LHR could handle quite a few more flights if both runways could be used for both takeoffs and landings interleaved.

[419]

Here's one that's had me puzzled for a while.

I've noticed that on the upper surfaces of the wings on an Airbus A319, (and probably on other aircraft as well), there are orange coloured brackets, which have holes in them.

They look a bit like tie down brackets that are fixed to the underside of small fixed wing planes, but obviously they can't be for this purpose.

Are they something to do with rigging checks on the flight controls, or do they have a totally different use?

[SLFguy]

Good Lord peeps! It's a well know fact that the flashing lights & whistles are provided in the event that the a/c crashes into a disco.

[EchoMike]

This discussion brought a smile to my face . . .

A few years ago we had some moronic person get elected to a minor office here. (Says something about who voted for her, but that's another subject.)

Anyway, she had aspirations for bigger things, and figured one of the ways to get there was to attack waste and fraud in the county government. OK so far.

Her target for today was the Sheriff's Department "air wing", a couple of helicopters and an older turboprop (old King Air, if I recall correctly) which was used for prisoner transfer and executive transport (there's a difference?) around the state.

She got the idea that there was an optimum speed for the operation of this aircraft, and decided to see if it was being observed. Her next step was to subpoena (request under due process of law) the logbooks for the airplane.

She discovered that a trip to the state capitol had taken one hour 10 minutes and the trip back took only 50 minutes. She had the pilot subpoena'ed for the hearing (you gotta show up or they arrest you) and accused him loudly and publicly (and it was in the newspapers) of not operating the aircraft at the optimum speed. Clearly she wanted the pilot's scalp and the Sheriff's too, if she could get it.

Under oath, on the stand, in front of the judge, in response to her hysterical accusations, the pilot said one single word in his defense: "Headwinds."

Judge: "Case dismissed."

She was not re-elected and went back to being an estate agent.

Best Regards,

Echo Mike (pilot, and yes, winds make a difference!)

[TheChitterneFlyer]

Be cautious with the statement that the slide will deploy if the door is opened from the outside... not true in all cases dear chap. The Tristar outer handle mechanically detatched the girt bar so that the slide wouldn't deploy if the door was opened from the outside... that's a fact! This did indeed prevent two instances, that I know of, of the ground staff opening the door from the jetty when the inside handle was in 'auto' (armed). I can't speak for all aircraft types, so it's therefore wise to assume that the slide will deploy... get out of the way!

TCF

[TightSlot]

419 - Reasonably sure that what you are referring to is known as a 'D' Ring. It is used primarily in a ditching. Inside the frame of one or more overwing exit hatches on each side is an escape rope: In a ditching this is taken out onto the wing and attached to the 'D' ring. This provides a handhold and some stability to those who may evacuate onto the wing in a ditching.

[419]

Thanks for that.
I suppose that would account for them being painted bright orange, so that they can easily been identified in an emergency situation.

[llanfairpg]

This is your captain speaking and I have some advice for you.

The one that catches everyone out is how does the aircraft still go forward when the wheels are retracted, thats got you hasnt it.

By the way for ditching, history shows that aircraft float better than passengers so always grab a passing wing in preference to a passenger.

Never worry about hypothermia after ditching, sharks often eat cold meals.

Never inflate your life jacket inside the aircraft so dont forget to take the instructions with you.

Notice the light on your life jacket, no one else will!

You will also notice a whistle on your life jacket, you may think this to be useless but submarines can pick up the slightest noise a long way off, sadly so do Sharks

Transatlantic flights carry life rafts and crews practice with them in the local swimming baths, honestly the only difference is the ocean is cleaner.

To be safe always sit in the emergency row, this means you will get out first unless you are carrying a rugby team or Jo Brand, then you will be trampled to death.

In the event of an evacuation do not forget to take off your high heel shoes because you will puncture the slide and the people behind you will be very pissed off because the slide now not only looks like a giant used Durex, it behaves like one too.

After a major accident you will be interviewed by the press. Make sure you say that the the pilot was wrestling with the controls to avoid a school and village because the press love this, adding that you are having an affair with the captain could lead to a series on Channel Four.

Remember that the captain always leaves the aircraft last of all in an emergency, if you should see me pushing past you shouting, "I told you they should have changed that engine" you are to immeadiately assume the role of captain.

Cabin Crew do not like be referred to as waitress, babe, shagger or mate even on services into Newcastle, so remember you should really be saying, "excuse me safety attendant do you think you could lift this xxxxing wing spar of my legs please," substitute, 'pissed passenger' at your discretion on Spanish flights.

When you check in you will always be asked 'did you pack you own bag.'?
Its not a good time to admit that your mother had to iron all your shirts, put your name in your coat and pack you case.

If you arrive late you wont get on the flight and you will be really pissed off and might feel like behaving like a complete ******, just before you do just check your not flying Easy Jet because you may be on TV too.

If you are British and do not have a valid passport with you you will not be able to travel, if however you are from any other country dont worry and in addition by the time you return you will probably have qualified for a flat and job seekers allowance.

Your probably wondering what airline I work for well all I am going to tell you is that our aircraft are so old I flew one the other day with;

'Dick Turpin is innocent' on the nose.

Good night and remember aircraft are only dangerous when pilots get into them

[Contacttower]

Never inflate your life jacket inside the aircraft so dont forget to take the instructions with you.


When the hijacked Ethiopian 767 crashed off the coast of Africa it became clear that a number of the passengers had...despite being told by the captain minutes before impact NOT to inflate their life jackets...done just that: inflated their life jackets inside the cabin.

The results were predictable, when the plane hit the water it filled so quickly passengers had to dive under water in order to get to the exits. Those who had not inflated their life jackets could hold their breath and dive for it. Those who had inflated their life jackets floated to the top of the cabin and were trapped against the ceiling.

Listen to the safety briefing, it might one day save your life.

[llanfairpg]

As with everything follow the rules and procedure and you will not go far wrong--just before your next trip to the airport just stop and ask yourself when was the last time you read the Highway Code?

[StaceyF]

Why does it take me >10hrs to fly to the Carribean from the UK but <9hrs to fly back?

I'm guessing Earth rotation?

[Final 3 Greens]

Try jetstream activity from W to E.

[Atishoo]

Wind up ya bum?

[Atishoo]

What is happening when the plane seems to fall out of the sky for a few seconds, then theres a roar of the engines?

I will never know while its happening as im too busy having a heart attack !!

[llanfairpg]

What is happening when the plane seems to fall out of the sky for a few seconds, then theres a roar of the engines?

I will never know while its happening as im too busy having a heart attack !!


In the trade we call that bit 'LANDING'. Dont worry about that bit, its the bit after that that causes the problems. If you notice the floor bow a little or the overhead bins come down thats the time to have your heart attack

[Henry Hallam]

"I do accept that whatever the PIC says goes - so no worries - but am curious as to WHY someone would not allow the use of a handheld GPS receiver in the back. It is a after all a RECEIVER - or does it actually transmit anything that could interfere with instrumentation?"

In theory: All radio receivers also emit a signal from the local oscillator. The better/more expensive ones emit less of it. The GPS signal is especially weak and sensitive so it is possible to be interfered with. I have noticed that running several GPS receivers in close proximity to each other causes reduced signal quality and sometimes loss of signal on some of them.

In practice: The aircraft equipment is much too far away from your receiver for this to be a problem. It also has nice big antennae and high quality amplifiers. And, the pilot doesn't know about this. Almost all pilots wouldn't mind you using a portable GPS so in reality this is probably just CC being jobsworths.

[PAXboy]

Hallambut am curious as to WHY someone would not allow the use of a hand held GPS receiver in the back.Start with this current thread: http://www.pprune.org/forums/showthread.php?t=303721

It contains all the key components of the argument that has been told here a dozen, dozen times. May I suggest that you pay particular interest in the posts of radeng aka Radio Engineer. If he says that he does not wish to be on an aeroplane that is conducting unplanned and random experiments with radio devices - then nor do I!!!

[TightSlot]

probably just CC being jobsworths

Never miss an opportunity eh, Hallam? Pity about the facts proving otherwise, though...

[Blacksheep]

airbus- you are incorrect. The B737 has a manual selection of arming and disarming the doors. You open an armed 737 door from the inside or the outside and you will get a surprise!
Sorry to contradict you, but on the B737 pulling the external handle clear of the stowed position mechanically disengages the girt bar and thus disarms the slide. It doesn't really matter what aircraft you consider, this is a primary safety design requirement for door mounted escape slides - main entry door or overwing - intended to protect emergency services personnel in an incident/accident where the slides may still be armed.

Despite the "Doors to Manual and Cross check" (or "Disarm Slides and Cross Check") procedures we frequently experience accidental door slide deployment by both cabin and flight deck crew, yet the safest way to handle doors is for them to never be opened from inside the aircraft unless they are armed and it is a proper emergency evacuation.

[TightSlot]

Blacksheep

To date, I've operated as Cabin Crew on B737-200/300/400/500 & 800 types and flown as passenger on -700's: None of them had (or have) anything more sophisticated than a manual Girt Bar mechanism for arm/disarm, with no mechanical linkage. For the reasons that you state above, a red warning strap is often placed over the door viewport after arming. I have never heard of a B737 with such a door mechanism that enables automatic disarming of the manually operated Girt Bar.

I note that you're a volume contributor to PPRuNe, so with great respect...

Do you think it possible that your memory on this one has been affected by a surfeit of Xmas cheer? Has Santa provided too much Succour?


:E

[WHBM]

Why does it take me >10hrs to fly to the Carribean from the UK but <9hrs to fly back?

I'm guessing Earth rotation?
Correct, but in a longwinded way.

Yes that's a pun but it's after Christmas so I am excused.

Because of the earth's rotation winds tend to flow from the west. This is caused by a combination of the atmosphere "slipping" relative to the rotating earth mass, and also the heating effects of the sun when it is exposed to the earth surface compared to nighttime when it is not. In addition to the westerlies, air tends to flow from the Equator to the poles as well.

Because of this (and forget any local weather systems passing through, up at jet altitudes you are above those) there is a constant westerly wind, so aircraft heading west are fighting a headwind while those coming east are gaining a benefit. Exactly the same used to happen in the days of sailing ships crossing the Atlantic.

Winds up at altitude are much greater than down where we live on the surface. To prove this just climb up to the top of a mountain peak. Rule of thumb is whatever the wind is at ground level it is double that 1,000 feet up. This is due to surface drag, which slows the wind nearest the surface down.

Because the winds are variable and change from hour to hour, there is much to be gained by predicting what the relative wind is on each side of your intended course, as it may be that you can gain by taking a different route. For example when going to the Caribbean you may notice that sometimes you route out direct over Lands End and Bermuda, whereas other times you are far to the north, and may indeed sometimes pass over Newfoundland, which is actually giving a shorter time that day, while those coming the opposite way are trying to get into the fast winds, especially the very strong but surprisingly narrow band called the Jetstream.

All other things being equal westbounds normally find it better to be further north than eastbounds. This is true crossing both the Atlantic and the Pacific - Hong Kong to New York for example routes across the Pacific and Canada coming east but often gets up over the North Pole going west. Major airlines have a whole department in Flight Operations who plan all this each day; if you have a meteorology degree from University they will be pleased to see you.

[perkin]

Correct, but in a longwinded way

Incorrect, sorry! Earth rotation not involved, atmospheric circulation is primarily the result of a complex-ish interaction between atmospheric and oceanic circulation, caused by heating and cooling and, in the case of oceans, variations in water density (salinity) which is also partly the result of temperature variations.

Atmospheric circulation is primarily the result of oceanic circulation - take the example of the El Nino variation in Pacific Ocean circulation and the effect that this can have on global weather patterns.

[Memetic]

Back up the thread a question was asked about carrying life rafts.

For many of the larger aircraft types the slides detach (can be detached ) and float to become life rafts - uncovered and hence not great for exposure protection but able to get PAX out of the water / provide buoyancy.

There are also slide/raft variants (not sure what the criteria for needing them is or whether its a cost option) which usually have canopies, survival packs, paddles etc. like a conventional life raft.

Checking what I thought I knew turned up : http://en.wikipedia.org/wiki/Evacuation_slide#Types_of_slide

[Memetic]

What happens at check in if when asked, "Did you pack your bag yourself."

I answer, "No, the butler packed it."

It always bothers me to lie and say I packed myself ;)

[Rollingthunder]

" What happens at check in if when asked, "Did you pack your bag yourself."
I answer, "No, the butler packed it."

The check-in clerk sighs, rolls his/her eyes and proceeds to open your luggage and inspect every article in it.


What happens at check-in if when asked, "Was the baggage out of your possesion at any time and you answer - well it was in the hold of a bus for a couple of hours". See above.

[Atishoo]

llanpg

Noooooooooo..... not when descending. This has happened when we have been half way through the journey, not taking off and not landing, just bobbing along like !!

[Contacttower]

probably just CC being jobsworths


Don't get at CC if you don't like the rules...as it happens handheld GPS has been discussed recently and the upshot is some airlines allow it some don't. But it's not the CC's fault if the airline doesn't allow them and I doubt they enjoy enforcing the rules particularly.

[pax2908]

Hello, I shall now display my blatant ignorance and ask a few questions:
- when I send positive comments to Customer Relations, will my letter or message be transmitted as such to the person(s) concerned, or just a summary (like date and time or flight number)?
- when I fill a "satisfaction survey" on board, will it be interpreted as representative of the people with whom I interacted (crew/ground staff/reservations), OR rather as representative of the commercial policy of the airline?
- one particular airline includes the following question on their survey: "should the travel class reflect one's social status?". Could someone please explain to me, in simple words, what it means?

Thanks

[Aqua]

I don't work in the airline industry so have no idea if this (http://news.bbc.co.uk/1/hi/uk/4724169.stm) is true or not.

If your plane lands or crashes into the sea, you won't be needing the lifejacket, or the whistle to attract attention.

Life jackets are useful in a number of airports where planes might overshoot the runway into water but otherwise the safety authorities struggle to point to one life saved by them in the history of large passenger planes.

What the lifejacket really does is offer an illusion of safety to overcome an illusion of danger.