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liam548
13th Oct 2011, 11:37
Surely they had some?

BBC News - 'Inexperience' led to fatal balloon crash in Somerset (http://www.bbc.co.uk/news/uk-england-somerset-15275931)

Cacophonix
13th Oct 2011, 11:42
As a result of the accident the AAIB has said the BBAC will be producing information for high-altitude flights.

That would have been useful! :ugh:

One man who knew what he was about at altitude...

http://upload.wikimedia.org/wikipedia/commons/thumb/8/81/Kittinger-jump.jpg/220px-Kittinger-jump.jpg

Caco

bob johns
13th Oct 2011, 12:03
23000(qnh) in Baron Tari to Mendi in empty aeroplane F-- all fuel and between layers light rain. tried to light a smoke and the match wouldnt light !!. MAP about 13 inches ,rpm 2600 then Mendi WAS there . Techniqe was to slow to 140, kt full pitch ,gear down , FULL FLAP and stick the nose DOWN!! and keep the cowl flaps closed and dont look at the CHT gauge !!because you are in the aeroplane and Junior or Helly was nt

bob johns
13th Oct 2011, 12:13
must explain in PNG highlands in 1976 before global warming ,and PC .

Cacophonix
13th Oct 2011, 12:16
23000(qnh) in Baron Tari to Mendi in empty aeroplane


What's the time of useful consciousness at 23000 feet for the unaclimatised at 23000 feet? Can't be long...! :ooh:

dont look at the CHT gauge

What was the mean time BTO for the Baron's cracking cylinder heads? ;)

Caco

Checkboard
13th Oct 2011, 12:37
A bit longer than 30 seconds at 30,000 feet - five minutes at 23,000. A bit less if you're having a cigarette ;)

Solid Rust Twotter
13th Oct 2011, 12:38
Don't talk and move as little as possible and you can manage. Used to throw out the odd load of skydivers at those levels way back from a turbocharged C210.

bob johns
13th Oct 2011, 12:52
tari to meni usually took about 20 min in a baron bearing in mind tari and mendi were 5600 ft amsl but terrain between was Mt Kerrawa and Mt Ne were 11000 and 13000 Between which was the Tari Gap! scrape the ground at 10000 amsl . only happened on odd occaisions when it was very urgent (that is going over the top when WX is RS )up to 30 min was not unusual and in most cases these aeroplanes were not pressurised and no oxygen was carried

rgbrock1
13th Oct 2011, 14:15
I used to regularly jump out of aircraft. But not at 20,000 ft.

http://i811.photobucket.com/albums/zz32/RonPaulo001/633974240143417145-usarmyrangers.jpg

visibility3miles
13th Oct 2011, 15:16
20,000 feet? No problem. :):):)
At 29,028 feet, Mount Everest is tall enough to poke into the jet stream, a high-altitude river of wind that blows at speeds of more than 200 miles an hour. Temperatures on the mountain can plummet low enough to freeze exposed flesh instantly. Its upper reaches offer only a third of the oxygen available at sea level--so little that if you could be transported instantly from sea level to Everest's summit, without time to acclimatize, you would probably lose consciousness within minutes. Kerosene cannot burn here; helicopters cannot fly here. Yet every spring, flocks of bar-headed geese--the world's highest-altitude migrants--fly from their winter feeding grounds in the lowlands of India through the Himalayan range, sometimes even directly above Everest, on their way to their nesting grounds in Tibet. Then every fall these birds retrace their route to India. With a little help from tailwinds, they may be able to cover the one-way trip--more than 1,000 miles--in a single day.
Audubon: Birds (http://archive.audubonmagazine.org/birds/birds0011.html)

http://archive.audubonmagazine.org/birds/images/B%20bargoose.jpg

Cacophonix
13th Oct 2011, 15:26
U.S. Army Rangers

I like to jump out of planes and kill people

rgbrock1 may I suggest that the Rangers reach for that metallic hoop called a rip chord when they jump out of planes and nobody will be killed!

:p

Caco

visibility3miles
13th Oct 2011, 15:32
a rip chord

What note or key is that?

Cacophonix
13th Oct 2011, 15:39
What note or key is that?

Somewhere between falsetto and a squeak when you realize there is too much space between the rip and the chord! ;)

Caco

rgbrock1
13th Oct 2011, 15:55
We don't need no stinkin' rip chord. Rip chords are for girls!!!!

Cacophonix
13th Oct 2011, 16:00
rgb

You and I would sing merrily all the way to the ground then, no rip cords but our chords would be perfect! ;)

Caco

Standard Noise
13th Oct 2011, 16:09
To answer the OP's question, they were carrying oxygen and two nasal cannulae, but for some reason, both valves on the oxygen cylinder were closed when it was inspected post accident. The pilot had ten years experience in balloons and had worked in the ballon industry but had not attempted such a flight before. Sometimes things go wrong and in this case tehy did, but AAIB could not determine one reason alone for the cause.

http://www.aaib.gov.uk/ (http://www.aaib.gov.uk/)

Cacophonix
13th Oct 2011, 16:34
From the official report... as posted by Standard Noise

At 22,000 ft (just above the peak altitude of the accident
flight) the time of useful consciousness is around
10 minutes, although there is great variation depending
on the individual. This figure also relates to sudden
exposure to that altitude. A gradual increase in altitude,
as happened during this flight, would mean that the
effects of hypoxia would build up during the ascent,
so the time of useful consciousness at the peak altitude
would be considerably less than this figure.

Sad that a seemingly well planned flight should end so badly.

Brought to mind the dangers faced by Nepalese helicopter pilot Lt. Col. Madan Khatri Chhetri, who in 1996 rescued climbers Beck Weathers and Makulu Gau near Camp I at approximately 20,000 feet (6,096 meters) on Everest.

First Helicopter Landing on Everest's Summit @ National Geographic Adventure Magazine (http://www.nationalgeographic.com/adventure/0509/whats_new/helicopter_everest.html)

Caco

Tankertrashnav
13th Oct 2011, 16:46
The bit that doesn't quite ring true about this is that whilst certainly most people would be experiencing hypoxia at around 22,000 feet, the affects would rapidly wear off as they descended. Anyone who has done the RAF procedure where you are rendered hypoxic in a decompression chamber, and then given silly tasks to do, will recall that when the oxygen supply is reconnected full consciousness returns within a very short time. The idea that they were still suffering from the affects of hypoxia as they hit the ground does not seem at all likely, although as I am not a balloonist I wouldn't know whether any ill-advised step with regard to valves they took while hypoxic was irrevocable.

Checkboard
13th Oct 2011, 19:10
Kerosene cannot burn here; helicopters cannot fly here.

indeed? I burn kerosene at much higher altitudes than that in my 737, and as for helicopters:

First Helicopter Landing on Everest's Summit @ National Geographic Adventure Magazine (http://www.nationalgeographic.com/adventure/0509/whats_new/helicopter_everest.html)

farsouth
13th Oct 2011, 20:42
indeed? I burn kerosene at much higher altitudes than that in my 737

I suspect by the time your kerosene burns, the air pressure is many, many times that of the pressure at 29,000 ft :)

Checkboard
13th Oct 2011, 21:08
OK - how about the primus stove (http://en.wikipedia.org/wiki/Primus_stove):

The Primus stove, the first pressurized-burner kerosene (paraffin) stove, was developed in 1892 ... The efficient Primus stove quickly earned a reputation as a reliable and durable stove in everyday use, and it performed especially well under adverse conditions: it was the stove of choice for ... Mallory on Mt. Everest as well as Tenzing and Hillary there many decades later.

Note: the "Pressurised" bit of the stove is simply to provide a supply of fuel - the flame occurs at atmospheric pressure.

No problem for them using Kero to make a pot of tea, then. :hmm:

Basically - flame and human survival require similar amounts of O2 - if you can breath, you may have fire.

Cacophonix
13th Oct 2011, 22:05
the flame occurs at atmospheric pressure.

As we know at 29000 feet, give or take a few feet, assuming we are trying for a brew up to celebrate our ascent to the top of Everest, the atmospheric pressure will be much lower than standard... averagely little less than 1/3 of that at standard atmosphere.

In fact if the stove was not pressurized e.g. primus ( also see self pressurizing kerosene stoves) it would be very difficult light the stove due to the inability to provide a flammable fuel/air mix although as you say there is sufficient O2 density to support combustion.

As the air becomes becomes less dense, the air contains less gases per unit of volume, and therefore less oxygen. Climbers suffer because they have to breathe faster to compensate for the relative lack of oxygen and exhale more CO2 that results in changes in blood acidity levels etc.

Caco

visibility3miles
13th Oct 2011, 22:31
Not to mention that it is bloody cold up there. Even if they did get more O2 for their brain on the way down, their fingers may have been too numb to be nimble.

Plus, hypothermia, which sets in gradually, seems to act like getting drunk, hence you make bad decisions, sometimes really bad decisions.

Primus stoves are good.

I once went on a weekend snowshoeing camping trip feet at about 3,000 feet ASL.

Good tent? Yes.
Good sleeping bag? Yes.
Good boots, warm clothing, and ensolite sleeping pad? Yes.
Fuel source? Liquid butane tank. Oops.

Bad idea, unless you sleep with it inside your sleeping bag overnight. For some reason, I was nominated to snuggle up with it in the morning until the gas was warm enough to be coaxed out to cook breakfast.

Brrr...

Cacophonix
13th Oct 2011, 22:42
Bad idea, unless you sleep with it inside your sleeping bag overnight. For some reason, I was nominated to snuggle up with it in the morning until the gas was warm enough to be coaxed out to cook breakfast.

The best primus stoves also include a preheat (generally just a priming pan). Very good design that has stood the test of time.

Question is would that priming pan actually burn on top of Everest? Mind you I doubt whether many have bothered to try and brew anything on top of Everest. Get up and get down quickly before you die!

Caco

G-CPTN
14th Oct 2011, 00:29
Fuel source? Liquid butane tank. Oops.
Bad idea,

Ani fule kno that propane is the gas of choice for low ambients:-
In order to be usable, the liquid in the bottle must be able to boil into a gas. In the case of Butane, this will happen at any temperature above -2C, whereas with Propane, this figure is much lower, at -42C. In the real world, it's not so clear cut. Whenever some of the liquid boils into gas, the remaining liquid cools. It is therefore possible for the temperature of the liquid to drop to several degrees below ambient. This can easily prevent a Butane canister from producing a useful gas supply, even when the outside temperature is several degrees above 0C

Loose rivets
14th Oct 2011, 01:07
I used to regularly jump out of aircraft. But not at 20,000 ft.

Me too. Bloody airstairs late again, I'd be out of that door on the way to the bar before you could say, Geronimo.


The pilot had ten years experience in balloons and had worked in the ballon industry


His hypoxia was thought to be caused by a shortage of elves helping to blow them up over the Christmas season.

Okay, this sketch is getting silly. I'm going to breath deeply.

Howard Hughes
14th Oct 2011, 08:23
Plus, hypothermia, which sets in gradually, seems to act like getting drunk, hence you make bad decisions, sometimes really bad decisions.

Also a symptom of Hypoxia!:ok:

Tankertrashnav
14th Oct 2011, 10:12
No problem for them using Kero to make a pot of tea, then. http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/yeees.gif



Yes, but not worth the effort. Not sure at what temperature water boils at 29,000', but considerably less than 100C. Tea will therefore taste vile, as anyone who has ever unwisely ordered tea in France and been presented with a lukewarm infusion will attest :yuk:

Cacophonix
14th Oct 2011, 10:22
Normal tap water (what the hell is that really one might ask?) will boil at around 70 degrees Celsius at 29000 feet.

I have always thought that of all the scientists Boyle was well named...

Caco

Cacophonix
14th Oct 2011, 11:17
For those interested in medicine, aviation (of all kinds), diving, mountaineering, engineering, physics or who just have some time to kill this is a fascinating read in Germanic English ...

http://tuprints.ulb.tu-darmstadt.de/2103/1/lunen_diss.pdf

Caco

When in 1874 a French team with Sivel, Croce-Spinelli and Tissandier
was formed to beat the altitude record by Coxwell and Glaisher, Paul Bert
supported this expedition in order to gain physiological data from the balloonists. The balloon was unintentionally taken up to 8000m, leading to the deaths of Sivel and Spinelli, and to severe injuries to Tissandier.

Bert was shocked by this tragedy and felt guilty about this outcome.
From then on he restricted himself to sole indoor experiments, i.e. experiments carried out in a controlled environment in the laboratory, using animals and himself as test subjects


When going to heights, the physiological problems that occur seem to be unrelated to the way one chose to reach that altitude. On the physical level,the decrease in ambient pressure, i.e. the deprivation of the inspired air with oxygen, is the same on a mountain top or in a balloon or aeroplane flying at the same height. It therefore seems natural to investigate both in the same context.

AvMed.IN
3rd Feb 2012, 11:20
Indeed there were lessons to be learnt from such tragedies - one of the most vital being that one must be able to recognise the symptoms of hypoxia to be able to take corrective actions within the time of useful consciousness.
Hypoxia Indoctrination (http://www.avmed.in/2012/02/hypoxia-training-essentially-useful/), using hypobaric or normobaric means, is a norm for many air forces as well as paratroopers the world over, with reasonable success.