Qantas 747 makes emergency landing due to hole in fuselage
John Levine
front of the right wing. The plane landed safely at MNL.
http://news.bbc.co.uk/2/hi/asia-pacific/7524733.stm
R's,
John
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Roland Perry
09:19:14 on Fri, 25 Jul 2008, John Levine <jo...@iecc.com> remarked:
>A 747-400 on the LHR-HKG-MEL route blew a large hole, 2.5m across, in
>front of the right wing.
Pictures of the hole show what appears to be individual bags inside the
hold - wouldn't you expect them to be in a container?
The "hole", however, seems to be more of a D-shaped external panel
that's come off.
--
Roland Perry
wiede...@googlemail.com
> In message <alpine.BSF.1.10.0807250821090.12...@simone.iecc.com>, at
> 09:19:14 on Fri, 25 Jul 2008, John Levine <jo...@iecc.com> remarked:
>
> >A 747-400 on the LHR-HKG-MEL route blew a large hole, 2.5m across, in
> >front of the right wing.
>
> Pictures of the hole show what appears to be individual bags inside the
> hold - wouldn't you expect them to be in a container?
the bags back. ( red bag )
other wise the hold would have been emptied?
>
> The "hole", however, seems to be more of a D-shaped external panel
> that's come off.
aerodynamic.
the primer green stuff behind that is the fuselage ( under pressure )
The wingbox should be in unpresurized space.
Which would imply that the joining to the (partial) pressure
bulkhread
failed.
wid
Roland Perry
<709a047d-9cb0-4c41...@s21g2000prm.googlegroups.com>, at
08:01:08 on Fri, 25 Jul 2008, "wiede...@googlemail.com"
<wiede...@googlemail.com> remarked:
>> Pictures of the hole show what appears to be individual bags inside the
>> hold - wouldn't you expect them to be in a container?
>afaics You can see the black straps of the pallet webbing holding
>the bags back. ( red bag ) other wise the hold would have been
>emptied?
I thought passenger bags were loaded into solid metal containers, not as
a pile held together by straps on some sort of base. Or are we seeing a
cargo pallet, and not a baggage one?
>> The "hole", however, seems to be more of a D-shaped external panel
>> that's come off.
>You have the D shaped fairing ( wing profile ) which is just
>aerodynamic.
>the primer green stuff behind that is the fuselage ( under pressure )
>The wingbox should be in unpresurized space.
>Which would imply that the joining to the (partial) pressure bulkhread
>failed.
So you are saying that two layers of structure have some off.
Would the loss of the D-shaped fairing cause the next layer to be
"sucked off", or is it more likely that the inner layer failing "pushed"
the fairing off as well?
--
Roland Perry
JF Mezei
the best I could find so far:
YOu can see the line delimiting the fairing. However, the air inlet
seems different. On the Korean Air aircraft, the inlet is a triangular
shape that starts at the first seam within the fairing and ends at the
3rd seam (which, when followed up, is the last seam before the metalic
wing root).
On the Qantas plane there seems to be a rectangular trap door at the 3rd
seam, but which does not continue forwards as do most other 747 I have
looked at on airliners. Any explanation ?
I would assume there there were strong structural elements aft of the
break that kept the remaining fairing in place. Otherwise, the wind
would have ripped it all apart.
The break happened just under the door, where there would be no seats
and there would be bulkheads nearby that may have strenghtened the cabin
floor.
It is a shame that there is only one angle showing the damage. Had they
had a picture from the front, it may have given much complementary
information.
It it had been only the fairing that fell off, there would have been no
reason for the pressure holding fuselage to break. So I would assume
that the fuselage broke, and the cabin pressure then popped the fairing
off.
In terms of luggage, it is quite possible that what we are seeing would
be baggage that "flew" due to the strong winds caused by the
decompression and got stuck in the hole by webbing or whatever. There
might be an intact container behind this. Note that many container are
open on one side and just covered with some sort of blanket. However,
it is also possible that what we are seeing is cabin luggage that went
through the reported cabin floor hole.
In such a decompression (which wouldn't have been that fast), would
there be a significant pressure build-up in a container, or would air be
able to flow out of it easily without causing the blanket cover to pop
off ?
.
Jeff
"John Levine" <jo...@iecc.com> wrote in message
news:alpine.BSF.1.10.0...@simone.iecc.com...
I know it is further aft than the cargo door (several of which have ruptured
over the years - United between HNL & AKL, Pan Am ex LHR, etc.) but wow.
JF Mezei
ruled out an explosion, possibly of an oxygen tank which is missing on
board.
Would anyone have noticed that there was no oxygen flowing out of masks
on a section of seats on board ?
.
wiede...@googlemail.com
> "John Levine" <jo...@iecc.com> wrote in message
>
> news:alpine.BSF.1.10.0...@simone.iecc.com...
>
> >A 747-400 on the LHR-HKG-MEL route blew a large hole, 2.5m across, in front
> >of the right wing. The plane landed safely at MNL.
>
> >http://news.bbc.co.uk/2/hi/asia-pacific/7524733.stm
>
> > R's,
> > John
> > --
> > misc.travel.air-industry is a moderated newsgroup. Please mail messages to
> > policies.
>
> I know it is further aft than the cargo door (several of which have ruptured
someone on de.rec.luftfahrt found the following link:
http://www.boeing.com/commercial/airports/arff/arff747.pdf
The current culprit seems to be oxygen bottles.
wid
Robin Johnson
missing-from-qantas-747-20080727-3lh1.html
Oxygen cylinder missing from Qantas 747
July 27, 2008 - 4:15PM
An oxygen cylinder is missing from the Qantas 747 jumbo that was
forced to make an emergency landing after a mid-air explosion punched
a hole in its fuselage, an Australian investigator said in Manila.
The Civil Aviation Safety Authority (CASA) is investigating whether an
exploding oxygen container was responsible for ripping a jagged hole
in the fuselage of flight QF30 from London to Melbourne last Friday.
The Boeing 747-400 was cruising at 8,800 metres with 346 passengers
aboard when it was shaken by the blast.
But the aircraft managed to land safely minutes later at Manila
airport, leaving passengers and crew unhurt but badly shaken.
"It is too early to say whether this was the cause of the explosion,"
Neville Blyth from the Australian Transport Safety Bureau (ATSB) told
a media briefing in Manila.
"But one of the cylinders which provides back up oxygen is missing."
Meanwhile, the Associated Press said Blyth told the conference
investigators had found no sign a bomb caused the hole.
He said tests for bomb residue were negative and Philippine officials
had bomb-sniffing dogs go through the hold, finding no indication of
explosives.
AFP said Blyth would not be drawn on the oxygen cylinder which is
roughly the size of a diver's scuba tank and he would not say how many
were on the aircraft.
He said investigators had ruled out terrorism saying: "There is no
evidence of a security related event here.
"Philippine bomb sniffing dogs have inspected the baggage and found no
materials of concern," he added.
Blyth said the investigation would take two to three days and a full
report on the findings "should be released in two to three months."
© 2008 AAP
Robin Johnson
asia/article4384017.ece
From The Sunday Times
July 27, 2008
Qantas jet drama ‘due to oxygen explosion’
A fault in the pilots’ emergency supply could have caused the near-
disaster
Steven Swinford and Paul Eddy
INVESTIGATORS are focusing on the possibility that exploding oxygen
tanks were responsible for blowing a gaping hole in the fuselage of a
Qantas Boeing 747 plane at 29,000ft.
A team from the Australian Transport Safety Bureau has found debris
scattered through the cargo hold from two oxygen tanks holding a two-
hour emergency supply for the pilots. The roof above them appears to
have been pushed up by the force of an explosion.
Investigators are working on the theory that the explosion was caused
by impact from loose cargo or the corrosion of the tanks themselves.
A source close to the Civil Aviation Safety Authority (CASA) in
Australia said: “It is looking extremely likely that one or more of
the oxygen tanks exploded. It’s never happened before so nobody knows
what caused it. It could be as simple as some cargo shifting and
smashing into it, which shouldn’t be able to happen.”
The investigators added, however, that it is too early to discount
metal fatigue, whereby the fuselage is weakened over time by the
expansion and contraction of the plane during take-off and landing.
This creates tiny cracks in the fuselage which are invisible to the
eye, but which can eventually give way.
Flight QF30 from London to Melbourne was an hour into its leg from
Hong Kong to Melbourne on Friday morning when a gaping hole appeared
in the front right side of the plane. Part of the ceiling in the
passenger cabin collapsed, some of the flooring gave way and debris
flew across the first class section.
Some passengers recorded the drama on their mobile phones. Footage
showed passengers sitting with their oxygen masks on as the 19-strong
crew continued to serve food, showing no sign of panic.
Captain John Francis Bartels, a former pilot with the Royal Australian
Navy, managed to put the aircraft into an emergency descent from
29,000ft to 10,000ft where the passengers and crew could breathe
without oxygen. He landed at Manila airport in the Philippines an hour
later.
Investigators are analysing debris in the cargo hold from the two
oxygen tanks. The tanks were bolted to the walls of the hold near
where the fuselage ruptured.
There were unconfirmed reports last night that the pilots had
experienced difficulties with their oxygen supply as they made their
descent. They have a backup in the cockpit in the event of the main
supply failing.
According to Bill Hamilton, a former pilot who flew Qantas 747s for
seven years, the bottles are made of toughened aluminium or carbon
fibre and would have been difficult to break. He believes corrosion
could have caused the tanks to rupture.
“There’s a saying in the engineering field that if you don’t find
corrosion you are not looking hard enough. The structural failures
I’ve heard of in the past have been corrosion-related or damage-
related and because of inferior repairs,” he said.
As well as the debris, investigators also found that the floor above
the tanks had been pushed upwards, which is more consistent with an
explosion.
The CASA source said: “In a normal depressurisation, if a fuselage had
metal fatigue and a hole was suddenly ripped in it, everything would
be sucked down and out. But in fact the floor above the bottles has
been blown upwards, which is more consistent with an explosion.”
Geoff Dixon, chief executive of Qantas, denied that corrosion caused
the hole. According to the CASA, corrosion was identified during a
month-long maintenance check in February, but the damage was minor and
further back in the plane. It had previously undergone a more thorough
check in 2004.
Although the plane is 17 years old, it is still considered relatively
young by aviation experts because long-haul aircraft make relatively
few take-offs and landings, which put strain on the fuselage.
If the oxygen tanks are to blame, the repercussions for the rest of
the 700-strong fleet of 747-400s are likely to be limited. Most do not
carry the large tanks used on flight QF30, which are standard issue on
planes whose path takes them over the Himalayas. They need larger
supplies before a plane can be sure of dropping to a safe altitude of
10,000ft. The majority of 747-400s in service use chemical oxygen
generators, which are less volatile.
Explosive decompressions such as that suffered by the Qantas jet are
rare, with about 20 incidents in the history of commercial aviation.
The most recent took place in 1989, when nine people died on a United
Airlines 747-122 when the cargo door blew out after it left Hawaii for
Australia. Qantas has never lost a jet aircraft to an accident. Its
record was emphasised in the 1988 movie Rain Man, where an autistic
character played by Dustin Hoffman insists on flying with the airline.
John Levine
>on a section of seats on board ?
Yes, and some news reports say that passengers complained that the
masks didn't work.
JF Mezei
from one of the O2 tanks in the passenger cabin. So the theory is that
the valve separated from the tank, was thrown up through the cabin
floor, while the tank would have gone the other way, punching itself a
hole to the outside. (obviously, the angles of this would have to be
verified).
Scuba tanks are normally filled with compressed air. If those are filled
with compressed O2, the issue of corrosion would be far greater.
JF Mezei
> A 747-400 on the LHR-HKG-MEL route blew a large hole, 2.5m across, in
> front of the right wing. The plane landed safely at MNL.
The ATSB has released a prelimiary report on the incident. Pictures of
the aircraft interior included.
http://www.atsb.gov.au/publications/investigation_reports/2008/AAIR/pdf/AO2008053_Prelim.pdf
(accessible from the main page at http://www.atsb.gov.au/ )
What is missing is a detailed picture of an undamaged #4 cylinder
aparatus so we could compare.
No mention of passenger injuries, but I had read elsewhere that a number
of passengers had to be hospitalised due to severe ear aches etc. (rapid
depressurisation followed by rapid repressurisation as aircraft
descended rapidly --- oops, to use modern terminology: "as the aircraft
plunged from the sky" :-)
Now, what puzzles me the most is the trajectory of the cylinder.
ATSB says cylinder shot up into main cabin, moved the door level to an
almost "open" position (fracturing the door mechanism so the lever moved
without moving the door latches), then shot up to damage the ceiling,
fell back down to the floor and then was sucked out through the small
hole on the floor it had created and out the plane.
OK, so the cyclinder somehow fractures in two, or loses its bottom. It
propells the bottom downwards and that creates the hole in the fuselage.
The top portion of cylinder then shoots up into the cabin.
If it had been just the valve breaking up, the the valve might have been
sent up to the cabin (creating a much smaller hole), and the cylinder
would have simply pushed itself out of the plane real fast. (with no
excursion into the main cabin).
What I find rather odd however is that the spent cylinder, after its
excursion all the way to the main cabin ceiling, would fall back on the
floor and be sucked out of the plane through the same small hole it had
created instants before. Upon falling on the floor, the cyclinder would
be in horizontal position and while it might have rolled towards the
hole, wouldn't it have been unable to fit through the hole in its
horizontal position and remain in the cabin, obstructing the flow of air
through the hole ?
What are the odds of the cylinder falling back down to the floor in
vertical orientation and right above the hole it had created and just
travel back down to cargo deck and be sucked out ?
A whole cyclinder might have the energy to go through the floor into the
main cabin, but once it fell back on the floor, I would think it would
be too heavy to just be "sucked" out, especially since in a horizontal
position, it would not fit through the small hole on the floor.
These cyclinders are steel, and quite heavy.
I know that for scuba diving, cyclinders have to be pressure tested at
regular intervals. I would assume the same for aircraft O2 tanks. These
things just don't crack open like that.
I wonder if they will be able to find a real reason for this incident.
.