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Topic: Safety Features Inside An Airliner
Username: Stickers
Posted 2007-09-13 18:50:50 and read 3711 times.

Hi Everyone

I wonder if anyone in the know could shed some light on a safety features question.

I have recently flown on an old 737-200, an old DC 9-32, a relatively new 737-800 and an almost brand new Airbus A319. Comparing the interiors of the old and new aircraft, there are very little if any dicernable new safety features INSIDE the plane. There is little differnce in the passenger safety features, (belt, seat, oxygen mask, etc.) between a brand new plane and a 30 year old one. Yet with all the advance in technology, it seems to me that the philosophy is one of "Lets make the plane as safe as possible from a flight and flight deck point of view so that it doesn't crash, because if it does everyone will die anyway. Therefore we won't spend too much time on interior safety features directly connected to the passengers and rather spend the money on avionics, navigation etc safety features."

Admittedly, this philosophy has worked well and we are all very grateful to the safety engineers involved in building airliners, this has led to Air travel being by far the safest form of transportation. However, with the recent tradgedies in which so many were killed, and given the low survival rate of people involved in crashes, i can't help wondering if some technological advancements on safety in the aircraft wouldn't go amiss.
For instance, a new design of seat, or seat belt. Make it an over the shoulder belt or something. That can't be too complicated. Maybe even investigate if the seats should be turned around?!? Perhaps an interior fire sprinker system. What about technology that has become common place in cars being put to use in Airliners, such as Airbags or something.  rotfl 
I know it sounds funny, and i'm not a safety engineer, but perhaps some new saftey measures could help. Given the price of the planes, i'm sure a little extra on safety, and making people feel safe wouldn't be unreasonable.

If someone knows of any ways in which INTERIOR passenger safety features have improved, i would love to hear it, or if there is a different philosophy than what i have mentioned that is applied by Boeing and Airbus and others.

Thanks
Stickers.  Confused

Topic: RE: Safety Features Inside An Airliner
Username: NWADC9
Posted 2007-09-13 18:54:58 and read 3703 times.

I think something to do with the evacuation slides being silver nowadays instead of the old yellow is one of the improved safety features in airliners today. I forgot what changed besides the obvious color change. Anything?

Topic: RE: Safety Features Inside An Airliner
Username: AirTranTUS
Posted 2007-09-13 19:09:57 and read 3679 times.

Quoting Stickers (Thread starter):
Perhaps an interior fire sprinker system.

That would be very, very heavy and would not be much of a benefit because it will not a help suppress a fire on the wings, where the fuel is.

Quoting Stickers (Thread starter):
Maybe even investigate if the seats should be turned around?!?

I think it has been proven that this will help passengers survive a crash. The only thing is, will they survive the crash to die in the fire? A violent crash will surely break bones, and they will not be able to move. Their death will now be slow and painful instead of quick.

Quoting Stickers (Thread starter):
such as Airbags or something.

Same as the rearward facing seats, survive crash, die in fire.

Quoting Stickers (Thread starter):
Make it an over the shoulder belt or something.

A passenger could not (or it would be more difficult to) assume the brace position with a shoulder belt. I don't know if the two different ways have been tested, but it would be interesting to see if a shoulder belt was more effective than the brace position.

Topic: RE: Safety Features Inside An Airliner
Username: Airfoilsguy
Posted 2007-09-13 19:38:42 and read 3648 times.

Don't some seat belts have airbags in them now?

Topic: RE: Safety Features Inside An Airliner
Username: RoseFlyer
Posted 2007-09-13 20:07:12 and read 3635 times.

Unfortunately most safety features are reactionary to major accidents. However there have been two big interior safety developments in the last decade.

The first was with smoke detectors and fire supression systems. Before the valujet crash, fire supression was not thought to be important in the sealed cargo bins since the oxygen supply is finite and the fire will self extinguish. Unfortunately that is not totally correct if you put oxygen generators in there. So now there are better systems on board planes.

The second is with insulation. After the Swissair MD-11 caught fire and crashed in the Atlantic, there is more effort put into installing proper insulation in the plane so it will not burn.

And of course there have been many improvements in seat design. They are safer now. The fabrics and materials won't burn as much. Also they should be able to sustain higher forces. There is the possibility of going to interiors that can sustain 16Gs, but that is only now in the military world. But you might see more of it in commercial aviation with programs that use commercial airplanes for military roles like the new Wedgetail and P-8 Poseidon aircraft that are based on the 737 for example.

Quoting Airfoilsguy (Reply 3):
Don't some seat belts have airbags in them now?

Yes they do. They aren't full huge airbags like on a car, but they will help cushion you when you are being pulled forward and the belt is resisting you.

Topic: RE: Safety Features Inside An Airliner
Username: Tristarsteve
Posted 2007-09-13 20:09:07 and read 3632 times.

Quoting Airfoilsguy (Reply 3):
Don't some seat belts have airbags in them now?

Yes, they can be fitted on the row of seats facing a bulkhead. There is a recent requirement that pax cannot hit their head on the bulkhead in a crash, you either make more space, or fit these belts.

Quoting Stickers (Thread starter):
Perhaps an interior fire sprinker system.

One was once designed, after the B737 crash at MAN in the earlt 80s., but it proved difficult to engineer in the event of acrash when the fuselage broke up. Fire blocking materials in the seats and furnishings was the way forward.

There has been a lot of advancement in the cabin, but it is not obvious to the passenger. Stronger seats that stay attached to the seat rails, overhead bins that do not fall down, fire resistant furnishings and seats, more space at emergency exits, and between galleys, automatic slides that inflate (they didn't use to!).

Look at the accident report for the B737-200 crash at Manchester, a lot of this came from that fatal incident.(about 1982)

Topic: RE: Safety Features Inside An Airliner
Username: Bok269
Posted 2007-09-13 20:12:31 and read 3631 times.

The reason you see the same safety features in a thirty year old DC-9 and a factory fresh 739 is that the regulatory industries require the same equipment across the board. The DC-9 may not have the same design of O2 masks as when it left the factory because the FAA, JAA, etc. requires newer designs. But you are correct, it is more important to prevent the plane from crashing.

Topic: RE: Safety Features Inside An Airliner
Username: KELPkid
Posted 2007-09-13 20:32:16 and read 3618 times.

Quoting Bok269 (Reply 6):
The DC-9 may not have the same design of O2 masks as when it left the factory because the FAA, JAA, etc. requires newer designs.

IIRC, doesn't the DC-9 (and most other aircraft from that timeframe) used bottled O2, whereas newer designs use Oxygen Generators?

Topic: RE: Safety Features Inside An Airliner
Username: Bok269
Posted 2007-09-13 21:19:54 and read 3605 times.

Quoting KELPkid (Reply 7):
IIRC, doesn't the DC-9 (and most other aircraft from that timeframe) used bottled O2, whereas newer designs use Oxygen Generators?

Im not sure about it. I was just using the DC-9 as an example since its been in service for a while and is still being used by Major airlines.

Topic: RE: Safety Features Inside An Airliner
Username: Tdscanuck
Posted 2007-09-13 22:18:13 and read 3585 times.

Quoting Bok269 (Reply 6):
The reason you see the same safety features in a thirty year old DC-9 and a factory fresh 739 is that the regulatory industries require the same equipment across the board.

Not exactly...without an AD, there is no way to require an older aircraft to meet a new requirement. Regulations are automatically grandfathered unless the FAA actively makes them retroactive. Most current production aircraft designs are uncertifiable under today's regulations.

Tom.

Topic: RE: Safety Features Inside An Airliner
Username: Bok269
Posted 2007-09-13 23:05:00 and read 3559 times.

Quoting Tdscanuck (Reply 9):

Not exactly...without an AD, there is no way to require an older aircraft to meet a new requirement. Regulations are automatically grandfathered unless the FAA actively makes them retroactive. Most current production aircraft designs are uncertifiable under today's regulations.

Tom.

Thanks for clearing that up. I stand corrected.

Topic: RE: Safety Features Inside An Airliner
Username: TristarSteve
Posted 2007-09-13 23:22:16 and read 3545 times.

Quoting KELPkid (Reply 7):
IIRC, doesn't the DC-9 (and most other aircraft from that timeframe) used bottled O2, whereas newer designs use Oxygen Generators?

The DC9 has bottled oxygen feeding the masks. The Tristar from 1972 had oxygen generators, but modern aircraft still have bottled oxygen. The BA B777 and B744 have bottled oxygen. It was found to be the easiest way to cover the emergency descent over the Himalayas case (you can't descend because of the high mountains), gaseous bottled oxygen lasts longer than generators.

And the dH Trident 2E which first flew about 1968 has no pax oxygen system at all.
The aircraft can descend so fast, it can get down from cruise altitude to 10000ft in the time allowed, so no oyxgen was fitted for the pax.

Topic: RE: Safety Features Inside An Airliner
Username: Jetlagged
Posted 2007-09-14 00:50:45 and read 3516 times.

Quoting AirTranTUS (Reply 2):
I think it has been proven that this will help passengers survive a crash. The only thing is, will they survive the crash to die in the fire? A violent crash will surely break bones, and they will not be able to move. Their death will now be slow and painful instead of quick.

With rear facing seats people will survive a greater crash deceleration. Bones break with impact, not deceleration. If your legs don't impact the seat in front, they won't break. Hence far fewer broken bones with rear facing seats. This gives people at least a fighting chance of escaping the resulting fire.

Topic: RE: Safety Features Inside An Airliner
Username: Tom12
Posted 2007-09-14 02:04:50 and read 3501 times.

Wasn't there something after that bmi 737 crashed, where the seats in the 737 were improved to take the force of upto 16G's, as much as the average person will only beable to handle something like 5, on that note though, a man took over 40G's in a test, caused some very temporary eye damage though.

Topic: RE: Safety Features Inside An Airliner
Username: Brenintw
Posted 2007-09-14 03:04:31 and read 3484 times.

Quoting Stickers (Thread starter):
For instance, a new design of seat, or seat belt. Make it an over the shoulder belt or something.

I remember reading that CX was looking at this with the Olympus interior that's just been launched. I haven't been in any of the new A/C yet, so can't say if it's actually been implemented or not. It was a system similar to the cabin crew's seats -- the shoulder strap was independent of the waist strap, so during cruise you can sit with just the waist strap fastened, but during landing and take-off, both straps are fastened.

It appears it didn't make it to the end ... I don't think it would be very practicable.

Topic: RE: Safety Features Inside An Airliner
Username: Qslinger
Posted 2007-09-14 06:07:42 and read 3436 times.

Quoting Jetlagged (Reply 12):
If your legs don't impact the seat in front, they won't break.

Ya, but not if the seat in front of you breaks from its railing and crashing into you, I can bet that would definitely break some bones. Your upper torso might be safe but thats not much use if u can't walk it anywhere..

Topic: RE: Safety Features Inside An Airliner
Username: Pilotpip
Posted 2007-09-14 06:31:53 and read 3433 times.

Quoting KELPkid (Reply 7):

IIRC, doesn't the DC-9 (and most other aircraft from that timeframe) used bottled O2, whereas newer designs use Oxygen Generators?

The O2 generators that were the catalyst for Valujet 592 came out of a company aircraft that was getting an overhaul.

Most aircraft will use a bottled system for the pilots and generators for the pax because the bottle system is very, very heavy.

Topic: RE: Safety Features Inside An Airliner
Username: KELPkid
Posted 2007-09-14 06:37:14 and read 3432 times.

Quoting Pilotpip (Reply 16):
The O2 generators that were the catalyst for Valujet 592 came out of a company aircraft that was getting an overhaul.

Yeah, a company MD-80  Wink

Topic: RE: Safety Features Inside An Airliner
Username: Pilotpip
Posted 2007-09-14 06:47:36 and read 3430 times.

Touche my friend. I forgot that part. It's been a long time since I looked at that report.

Topic: RE: Safety Features Inside An Airliner
Username: LongHauler
Posted 2007-09-14 14:48:05 and read 3357 times.

Quoting TristarSteve (Reply 11):
And the dH Trident 2E which first flew about 1968 has no pax oxygen system at all.

I looked at this with some scepticism, so I had to dig out British Airways safety cards to see for myself.

This is what I found:

The Trident, Trident One, Trident One-E and the Trident Three all did NOT mention Oxygen masks on the safety cards as you state, however the Trident Two DID.

Also both the B111-400s and -500s did not mention Oxygen masks.

Does this mean the aircraft were not equipped, or just not mentioned on the safety cards?

Digging further, and looking at BEA safety cards, it was the same ... no mention of Oxygen masks. In fact, even on the BEA Comet 4B safety card, there was no mention of the masks.

I thought maybe it was common not to mention them even if they were there in earlier days ... but not so, they ARE mentioned on British Airways and BOAC VC-10, B707 and Comet safety leaflets.

Any seasoned British Airways, BOAC, BEA crew that can clear this up?

Topic: RE: Safety Features Inside An Airliner
Username: MarkHKG
Posted 2007-09-14 16:26:19 and read 3331 times.

What are some of the biggest safety changes in my opinion?

- Flight attendant "direct view" and assist spaces

- Flight attendant assertive commands and evacuation management training

- Flight attendant Crew Resource Management

- Improved evacuation slide deployment reliability (still pretty bad though)

- Escape path lighting requirements

- Requirement of Halon extinguishers

- 16G Survival Rule

- Re-design of overwing exit for B737-NG aircraft

- Seat-Belt Airbags (Amsafe)

Quoting Brenintw (Reply 14):
I remember reading that CX was looking at this with the Olympus interior that's just been launched. I haven't been in any of the new A/C yet, so can't say if it's actually been implemented or not.

They have been, for the new J-Class. But this is purely to meet crash requirements as the "herringbone" design presents a lateral strike risk.

Quoting Airfoilsguy (Reply 3):
Don't some seat belts have airbags in them now?

Most noticeably, J-Class on Virgin, Air New Zealand, Jet Airways, Air Canada, Singapore Airlines (F and J). Again, many of these seats are herringbone design (other than Singapore), and the airbag had to be installed to meet lateral strike requirements.

Quoting NWADC9 (Reply 1):
I forgot what changed besides the obvious color change. Anything?

Slides typically automatically inflate (old MD-80 slides did not!)
Color changed to improve flammability standards.
Slides now inflate faster.
Slides also have a special ribbon to prevent inflation underneath the fuselage, rendering the slide useless.
Slide have to resist gusting of winds.
Slides can be disconnected rapidly for use as a flotation device, or in some cases, a slide/raft

SAFETY COULD STILL BE IMPROVED A LOT, but at least it's kinda better now!


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