Re: Greek plane crash questions

Thus spake "Bob Gardner" <bobmrg@comcast.net> :

>Thought we had gone through this before...must have been in another
>newsgroup.
>
>I have had the ineffable pleasure of being taken up to 25000 feet in a
>pressure chamber and then having the pressure dumped to simulate an
>explosive decompression. Your ability to hold your breath is
>immaterial....when the cabin decompresses, all air in your lungs is expelled
>forcefully. You have no control over it, so you have no breath to hold. Your
>only chance is to put on supplemental oxygen and do it as quickly as
>possible.

Me too, more like 12 seconds. Counted to something like 72, but I was
told that the last few kind of wandered all over the place. So loss
of conciousness is preceeded by a loss of thought process.

At 8000 meters, the oxygen that climbers use just barely keeps the
alive. Which is why Reinhold Messner is all the more amazing. Soloing
Everest without oxygen is a feat not yet duplicated.

Several climbers have bivied at high altitude without oxygen, but all
were "rescued" and climbed down on O2.

>
>The masks that drop from the overhead must be activated by pulling/jerking
>on the string to activate an oxygen generator...there are no little oxygen
>tanks up there. The crew has a separate oxygen supply, and if all is in
>order and everyone reacts properly, each pilot will reach over his shoulder,
>grab a quick-donning mask, and have it place and operating in a matter of a
>few seconds. I have no idea what happened in the case of the Helios
>airplane, but I do know that when the pressure vessel (cabin plus flight
>deck) decompresses, the noise is horrific, the atmosphere becomes foggy
>instantly, and loose papers fly in all directions. Training has to take
>over, because a calm, reasoned reaction is unlikely.
>
>Bob Gardner
>
>
>Bob Gardner
>"Harvey Deinst" <hdeinster1234@sbcglobal.net> wrote in message
>news:1usqdmp1axhvp$.r25032fqugz3$.dlg@40tude.net. ..
>> On Fri, 19 Aug 2005 15:38:24 -0400, Derf wrote:
>>> The problem with a quick decompress at cruise altitude is that
>>> the drop in pressure will almost surely cause one to exhale. Now you
>>> have only the oxygen already in the bloodstream until you get that
>>> mask on, and that means you have about 10 seconds of useful
>>> consciousness.
>>
>>
>> I'm VERY confused about this 30-second consciousness thing.
>>
>> I just exhaled and could still hold my breath for much more than ten
>> seconds. Maybe not thirty ... but I was conscious. I'd "guess" (no I have
>> no proof) then I'd be real panicky but I'd still be alive. Certainly if an
>> oxygen mask popped up in front of me after that 30 second period of no
>> air,
>> I'd grab at it like Barry Bonds eying a bottle of steroids.
>>
>> I am sure I must be wrong ... 'cause everyone is saying you have only ten
>> or fifteen seconds of consciousness ... but it seems to me you'd have a
>> minute or more (even BTK took three or four minutes of strangling to kill
>> a
>> person although I don't know how long they were conscious without blood to
>> their brains).
>>
>> Why would one only have 10 seconds, even with all the air pushed out of
>> their lungs by the decompression? I fundamentally don't understand this???
>>
>> --------------------------------------------------------------------------
>> Aviation experts believe the Helios Airways plane that crashed in Greece,
>> killing all 121 people on board, may have suffered a catastrophic loss of
>> cabin pressure, exposing those on board to extreme cold and lack of
>> oxygen.
>> Aviation commentator Mark Welsh explains how modern aircraft regulate air
>> pressure and temperature to allow safe flying.
>> Experts believe some Helios Airways passengers died before the crash
>>
>> Modern commercial aircraft operate at altitudes which cannot sustain human
>> life.
>> To provide a comfortable environment, the cabin of the aircraft is sealed
>> and the flow of air in and out of this "metal tube" is carefully
>> controlled.
>> The flow of air out is regulated by several valves in the body of the
>> aircraft and the flow of air in is provided by compressed air taken from
>> the engines.
>> WARNING SIGNS
>>
>> At high altitudes the concentration of oxygen in the atmosphere is much
>> lower
>> Starvation of the body's supply of oxygen is known as hypoxia. Early
>> symptoms may include headache, nausea and deeper breathing as the body
>> attempts to compensate
>> Breathing may become shallow as the person becomes weaker and the brain
>> realises it is expelling too much carbon dioxide and creating a harmful
>> imbalance of oxygen to CO2 in the body. They may lose consciousness.
>> Cyanosis - blue or purple discolouration of extremities such as the lips
>> and fingers - occurs as hypoxia progresses
>>
>> This air has its temperature and pressure corrected before being fed into
>> the cabin. If the regulating valves fail or if the cabin structure is
>> breached (by a failure of a door or window for example) then the pressure
>> in the cabin would suddenly drop to match the outside air pressure.
>> If there was a failure in the air supply system then the pressure would
>> decrease more slowly but still eventually match the outside air pressure.
>> If an aircraft flying at an altitude of 35,000 feet were to lose its
>> pressurisation system completely, then the occupants would have 25-30
>> seconds to establish an alternative oxygen supply. If they were unable to
>> do so they would die within two minutes.
>> To combat this threat, aircraft have a warning system which alerts the
>> crew
>> if the cabin altitude is approaching dangerous levels.
>> If this alert is received, the pilots should put on masks which will
>> provide them with oxygen while they rapidly descend the aircraft to an
>> altitude where the occupants can breathe without assistance.
>> While this is happening, the passengers will be provided with oxygen from
>> drop-down masks which will give them oxygen for 12 to 15 minutes, by which
>> time the aircraft should be at a lower level.
>> Oxygen supply
>> As well as air pressure, the aircraft's occupants must be protected from
>> the deadly outside air temperature. If the warmed flow of air into the
>> cabin were to fail, the temperature in the aircraft would decrease until
>> it
>> approached the outside air temperature of -45C to -60C.
>> The emergency oxygen supply used by the pilots is independent of that used
>> by the passengers. Any malfunction in this system would leave the pilots
>> with very little time to recover the situation.
>> If they were unable to do this, it is possible that the pilots would lose
>> consciousness, the aircraft would continue on autopilot and the cabin crew
>> and passengers would face a situation where they were running out of
>> emergency oxygen and the air temperature in the cabin was rapidly
>> dropping.
>> The cabin crew would have portable oxygen supplies and a means of opening
>> the locked cockpit door but would not be trained to fly the aircraft to a
>> safe altitude. With the cabin air exhausted and the temperature dropping
>> to
>> -50C, the aircraft would fly until it ran out of fuel.
>> Crucial data
>> The "black box" flight data recorder stores a huge amount of data gathered
>> from sensors around the aircraft.
>> This includes cabin pressure, the position of the flying controls and
>> aircraft height and speed. There is also a cockpit voice recorder which
>> will record noises, such as cockpit warnings, and conversations within the
>> cockpit.
>> Older voice recorder systems record sound onto a constantly running
>> magnetic tape loop while newer systems use digital storage devices to hold
>> much more voice data.
>> In the event of a plane crash, depending on the model of the recorder and
>> whether the data can be recovered, experts will be able to analyse cockpit
>> voice recordings for either the last 30 minutes of the flight or for up to
>> two hours before it crashed.
>>
>> GREECE AIR DISASTER
>>
>> 1. 0900 [0700GMT]: Helios Airways Flight ZU522 leaves Larnaca bound for
>> Prague via Athens
>> 2. 0920 approx: Plane reaches cruising altitude of 35,000ft
>> 3. 0937: Plane enters Greek airspace
>> 4. 1007: Air traffic control unable to contact aircraft
>> 5. 1030: Greek ATC issues "Renegade alert"
>> 6. 1055: F16 fighter aircraft scramble
>> 7. 1120: F16s intercept aircraft; pilots observed slumped over controls
>> 8. 1205: Aircraft crashes near Grammatiko, 40km north of Athens
>> ------------------------------------------------------------------------
>
--
dillon

Pain is Nature's way of saying "that was stupid"

Dillon, how about being kind to the dial up crowd, and cutting out the
9/10ths of the message that was not being replied to.

Thanks.
--
Jim in NC

On Thu, 25 Aug 2005 12:52:42 GMT, "Limey" <davidflies@noatt.crapnet>
wrote:

>
>"Bob Gardner" <bobmrg@comcast.net> wrote in message
>news:TM6dnaG99tPbn5DeRVn-rg@comcast.com...
>> With no warning that pressurization is going to be lost, it's kind of hard
>> to be prepared with any kind of gadgetry or procedure.
>
>Which is why, under FAA regs anyway, at least one flightcrew member is
>required to be wearing supplemental O2 at all times when above FL350.

The reg I think you're talking about is 121.333.

(2) When operating at flight altitudes above flight level 250, one
pilot at the controls of the airplane shall at all times wear and use
an oxygen mask secured, sealed, and supplying oxygen, in accordance
with the following:

(i) The one pilot need not wear and use an oxygen mask at or below the
following flight levels if each flight crewmember on flight deck duty
has a quick-donning type of oxygen mask that the certificate holder
has shown can be placed on the face from its ready position, properly
secured, sealed, and supplying oxygen upon demand, with one hand and
within five seconds:
(A) For airplanes having a passenger seat configuration of more than
30 seats, excluding any required crewmember seat, or a payload
capacity of more than 7,500 pounds, at or below flight level 410.

The way I read this they have to have it on over 250, if they don't
have a quick-don type.

Over 410 they have to have it on at all times.

In article <p5nPe.4080$IG2.1742@trndny01>,
George Patterson <grpphoto@verizon.net> wrote:

> If the objective of this is to exterminate the inhabitants, that's easily
> done
> by running a tube from the exhaust pipe of your car into one of the tunnels
> and
> running the car for an hour.

And you can buy an exhaust pipe connection kit designed for exactly this
purpose.

But aside from not particularly wanting to load my lawn up with exhaust
gases, there's the problem that the driveway is out in front of the
house and the problem area is way at the back of the lot.

Is forcing your car to sit and idle for a sustained period with the
exhaust pipe looking into the back pressure from 200+ feet of garden
hose a good idea? Guaranteed not to damage the engine? Or poison the
catalytic converter?

AES wrote:
>
> Is forcing your car to sit and idle for a sustained period with the
> exhaust pipe looking into the back pressure from 200+ feet of garden
> hose a good idea? Guaranteed not to damage the engine? Or poison the
> catalytic converter?

Dunno. My father just drove the car across the lawn to where the moles were.

George Patterson
Give a person a fish and you feed him for a day; teach a person to
use the Internet and he won't bother you for weeks.

In article <1124998559.862907.6080@g14g2000cwa.googlegroups.c om>,
Sbharris[atsign]ix.netcom.com <sbharris@ix.netcom.com> wrote:

>AES wrote:
>> This is OT from the O2 and human consciousness discussion that's been
>> going on in this thread, but perhaps some of the gas and breathing
>> experts who've been participating will know the answer off hand . . .
>>
>> I want to slow-flow CO2 into a bunch of mole and vole runs in a lawn.
>> If I purchase a CO2 flow regulator (about $60 retail), will it match the
>> fittings on any standard home fire extinguisher?
>
>
>Probably not. But why do you want to slow flow the voles anyway? More
>humane and probably more effective to flush them rapidly. Burrowing
>critters have good CO2 and O2 sensors, and if they feel it coming on
>slowly, they'll go out the backdoor if they have one.

Here's an extremely rapid way to introduce CO2 into the tunnel, as
implemented in a commercial device:

http://www.rodenator.com/rodenatorpro.html

It's a bit pricey for a device that just meters propane and oxygen and
then ignites them, but I guess they have to pay for liability insurance.


--
Norman Yarvin http://yarchive.net

"Peter Clark" <Invaldi@NotIn.YourLifetime.com.hatespam> wrote in message
news:9tnsg15sg4b6k3ruomt8rbomt0o5v55rsd@4ax.com...
> On Thu, 25 Aug 2005 12:52:42 GMT, "Limey" <davidflies@noatt.crapnet>
> wrote:
>
>>
>>"Bob Gardner" <bobmrg@comcast.net> wrote in message
>>news:TM6dnaG99tPbn5DeRVn-rg@comcast.com...
>>> With no warning that pressurization is going to be lost, it's kind of
>>> hard
>>> to be prepared with any kind of gadgetry or procedure.
>>
>>Which is why, under FAA regs anyway, at least one flightcrew member is
>>required to be wearing supplemental O2 at all times when above FL350.
>
> The reg I think you're talking about is 121.333.
>
> (2) When operating at flight altitudes above flight level 250, one
> pilot at the controls of the airplane shall at all times wear and use
> an oxygen mask secured, sealed, and supplying oxygen, in accordance
> with the following:
>
> (i) The one pilot need not wear and use an oxygen mask at or below the
> following flight levels if each flight crewmember on flight deck duty
> has a quick-donning type of oxygen mask that the certificate holder
> has shown can be placed on the face from its ready position, properly
> secured, sealed, and supplying oxygen upon demand, with one hand and
> within five seconds:
> (A) For airplanes having a passenger seat configuration of more than
> 30 seats, excluding any required crewmember seat, or a payload
> capacity of more than 7,500 pounds, at or below flight level 410.
>
> The way I read this they have to have it on over 250, if they don't
> have a quick-don type.
>
> Over 410 they have to have it on at all times.

You are correct, but 121.333 obviously is only applicable to Part 121
(Scheduled Carrier) ops. I was referencing a Part 91 reg which applies to
pilots of *any* aircraft, under General Operating Rules. Part 121 will
always be more restrictive (less tolerant) than Part 91.

Limey Dave.

On Fri, 26 Aug 2005 22:21:18 GMT, "Limey" <davidflies@noatt.crapnet>
wrote:

>
>"Peter Clark" <Invaldi@NotIn.YourLifetime.com.hatespam> wrote in message
>news:9tnsg15sg4b6k3ruomt8rbomt0o5v55rsd@4ax.com.. .
>> On Thu, 25 Aug 2005 12:52:42 GMT, "Limey" <davidflies@noatt.crapnet>
>> wrote:
>>
>>>
>>>"Bob Gardner" <bobmrg@comcast.net> wrote in message
>>>news:TM6dnaG99tPbn5DeRVn-rg@comcast.com...
>>>> With no warning that pressurization is going to be lost, it's kind of
>>>> hard
>>>> to be prepared with any kind of gadgetry or procedure.
>>>
>>>Which is why, under FAA regs anyway, at least one flightcrew member is
>>>required to be wearing supplemental O2 at all times when above FL350.
>>
>> The reg I think you're talking about is 121.333.
>>
>> (2) When operating at flight altitudes above flight level 250, one
>> pilot at the controls of the airplane shall at all times wear and use
>> an oxygen mask secured, sealed, and supplying oxygen, in accordance
>> with the following:
>>
>> (i) The one pilot need not wear and use an oxygen mask at or below the
>> following flight levels if each flight crewmember on flight deck duty
>> has a quick-donning type of oxygen mask that the certificate holder
>> has shown can be placed on the face from its ready position, properly
>> secured, sealed, and supplying oxygen upon demand, with one hand and
>> within five seconds:
>> (A) For airplanes having a passenger seat configuration of more than
>> 30 seats, excluding any required crewmember seat, or a payload
>> capacity of more than 7,500 pounds, at or below flight level 410.
>>
>> The way I read this they have to have it on over 250, if they don't
>> have a quick-don type.
>>
>> Over 410 they have to have it on at all times.
>
>You are correct, but 121.333 obviously is only applicable to Part 121
>(Scheduled Carrier) ops. I was referencing a Part 91 reg which applies to
>pilots of *any* aircraft, under General Operating Rules. Part 121 will
>always be more restrictive (less tolerant) than Part 91.

OK, but wasn't the aircraft in question a 121 equivalent operation? Or
was it a charter and thus equivalent to 135)?

But 91.211 says:

"(ii) At flight altitudes above flight level 350 unless one pilot at
the controls of the airplane is wearing and using an oxygen mask that
is secured and sealed and that either supplies oxygen at all times or
automatically supplies oxygen whenever the cabin pressure altitude of
the airplane exceeds 14,000 feet (MSL), except that the one pilot need
not wear and use an oxygen mask while at or below flight level 410 if
there are two pilots at the controls and each pilot has a
quick-donning type of oxygen mask that can be placed on the face with
one hand from the ready position within 5 seconds, supplying oxygen
and properly secured and sealed."

so there still isn't a requirement for O2 at all times over FL350 if
both are at the controls and the aircraft is equipped with
quick-donning masks. I'm not sure, are there any transport category
aircraft that don't standard come with quick-don?

In article <deo10802mos@news4.newsguy.com>,
Norman Yarvin <norman.yarvin@snet.net> wrote:


> Here's an extremely rapid way to introduce CO2 into the tunnel, as
> implemented in a commercial device:
>
> http://www.rodenator.com/rodenatorpro.html
>
> It's a bit pricey for a device that just meters propane and oxygen and
> then ignites them, but I guess they have to pay for liability insurance.

Thanks for the link! -- ya gotta love it!

Some of the groundskeepers at a certain major educational institution
not far from here are said to use this technique, on a home-brew basis.
The process is said to be quite impressive in action, but knowing the
general attitudes of our -- uh, their -- Safety Office, I guess it's
best not to say any more about this.

Also, for back yard use, gotta keep the kids and dog inside.

"Peter Clark" <Invaldi@NotIn.YourLifetime.com.hatespam> wrote in message
news:chavg1lntnmv7bo1lgolun28jd07ka8e8k@4ax.com...
> On Fri, 26 Aug 2005 22:21:18 GMT, "Limey" <davidflies@noatt.crapnet>
> wrote:
>
>>
>>"Peter Clark" <Invaldi@NotIn.YourLifetime.com.hatespam> wrote in message
>>news:9tnsg15sg4b6k3ruomt8rbomt0o5v55rsd@4ax.com. ..
>>> On Thu, 25 Aug 2005 12:52:42 GMT, "Limey" <davidflies@noatt.crapnet>
>>> wrote:
>>>
>>>>
>>>>"Bob Gardner" <bobmrg@comcast.net> wrote in message
>>>>news:TM6dnaG99tPbn5DeRVn-rg@comcast.com...
>>>>> With no warning that pressurization is going to be lost, it's kind of
>>>>> hard
>>>>> to be prepared with any kind of gadgetry or procedure.
>>>>
>>>>Which is why, under FAA regs anyway, at least one flightcrew member is
>>>>required to be wearing supplemental O2 at all times when above FL350.
>>>
>>> The reg I think you're talking about is 121.333.
>>>
>>> (2) When operating at flight altitudes above flight level 250, one
>>> pilot at the controls of the airplane shall at all times wear and use
>>> an oxygen mask secured, sealed, and supplying oxygen, in accordance
>>> with the following:
>>>
>>> (i) The one pilot need not wear and use an oxygen mask at or below the
>>> following flight levels if each flight crewmember on flight deck duty
>>> has a quick-donning type of oxygen mask that the certificate holder
>>> has shown can be placed on the face from its ready position, properly
>>> secured, sealed, and supplying oxygen upon demand, with one hand and
>>> within five seconds:
>>> (A) For airplanes having a passenger seat configuration of more than
>>> 30 seats, excluding any required crewmember seat, or a payload
>>> capacity of more than 7,500 pounds, at or below flight level 410.
>>>
>>> The way I read this they have to have it on over 250, if they don't
>>> have a quick-don type.
>>>
>>> Over 410 they have to have it on at all times.
>>
>>You are correct, but 121.333 obviously is only applicable to Part 121
>>(Scheduled Carrier) ops. I was referencing a Part 91 reg which applies to
>>pilots of *any* aircraft, under General Operating Rules. Part 121 will
>>always be more restrictive (less tolerant) than Part 91.
>
> OK, but wasn't the aircraft in question a 121 equivalent operation? Or
> was it a charter and thus equivalent to 135)?

I missed the original post, I just caught the post of yours that I responded
to, when it was cross-posted to rec.scuba.
>
> But 91.211 says:
>
> "(ii) At flight altitudes above flight level 350 unless one pilot at
> the controls of the airplane is wearing and using an oxygen mask that
> is secured and sealed and that either supplies oxygen at all times or
> automatically supplies oxygen whenever the cabin pressure altitude of
> the airplane exceeds 14,000 feet (MSL), except that the one pilot need
> not wear and use an oxygen mask while at or below flight level 410 if
> there are two pilots at the controls and each pilot has a
> quick-donning type of oxygen mask that can be placed on the face with
> one hand from the ready position within 5 seconds, supplying oxygen
> and properly secured and sealed."
>
> so there still isn't a requirement for O2 at all times over FL350 if
> both are at the controls and the aircraft is equipped with
> quick-donning masks. I'm not sure, are there any transport category
> aircraft that don't standard come with quick-don?
>
Absolutely correct, and I don't know, but none I've ever come across.

LD.