EMS helicopter down Oklahoma [Archive]

con-pilot

22nd Feb 2013, 16:14

This one happened almost in my back yard, literally. Less than a half mile, from their departure point to the accident site, the route of flight would have been right over our house. I did not hear the accident for a couple of reason, one I was sound asleep and secondly our house is so well insulated we cannot hardly hear anything from inside the house. I never heard any of the emergency equipment responding to the scene, but the local news helicopters did finally wake me up just after sunrise.

Sad event for sure. I have not bothered to go to the site and will not do so, seen enough accident sites in my life/career.

Two fatal, one survivor, no report on how serious the survivor is injured.

The Sultan

22nd Feb 2013, 16:34

Nurses from the Nursing home on the rushed to the crash and pulled out the sole survivor before a secondary explosion consumed the fuselage.

Why do all ASTARS seem to end up as a pile of ashes?

The Sultan

SARWannabe

22nd Feb 2013, 17:19

Very sad - RIP to the crew.

I see sunrise in Oklahoma at the moment is 7.06am so it was clearly 'Night'. Con-pilot: any first hand info on the weather this morning?

Gordy

22nd Feb 2013, 18:31

WX NOT a factor:

22 07:53 NW 9 9.00 Fair CLR 20 13 74% 10 NA 30.10 1020.6
22 06:53 NW 7 10.00 Fair CLR 20 13 74% 11 NA 30.08 1019.8
22 05:53 NW 8 10.00 Fair CLR 20 13 23 74% 10 NA 30.04 1018.6
22 04:53 N 12 10.00 Fair CLR 20 13 74% 8 NA 30.02 1017.7
22 03:53 NW 10 10.00 Fair CLR 21 14 74% 10 NA 30.00 1016.9
22 02:53 NW 12 G 21 10.00 Fair CLR 22 14 71% 10 NA 30.00 1016.9
22 01:53 NW 8 10.00 Fair CLR 22 14 71% 13 NA 30.03 1017.8
22 00:53 NW 13 10.00 Fair CLR 23 15 72% 11 NA 30.02 1017.6
21 23:53 NW 9 10.00 Fair CLR 23 15 35 72% 13 NA 30.00 1016.9

OvertHawk

22nd Feb 2013, 18:38

Respect to the people that pulled the survivor out!!! :D

con-pilot

22nd Feb 2013, 19:51

Con-pilot: any first hand info on the weather this morning?

Clear with unlimited visibility, light winds and cold. No factor really, least not that I can see.

It is now being reported on the local news stations that there was a fire in the cabin before the crash. Take that as you may, as I have read and been on accident sites where the aircraft was reported on fire before the accident, but when on scene, there was no sign of a post accident fire, let alone one airborne. So I don't put a lot of faith in these types of reports.

The accident site is approximately 2.5 miles north from Wiley Post Airport (KPWA). The airport is controlled, but at that time in the morning, the tower is closed. So whatever happend, it happend fast for them not to it make to Wiley Post, just two and a half miles away.

MightyGem

22nd Feb 2013, 22:57

Looks like it landed rather than crashed. So near, yet so far. :(

SASless

22nd Feb 2013, 23:51

O2 fires have killed crews before.....one that stands out is the Greenville, North Carolina Bell 206 crash many years ago. The O2 bottle was in the baggage compartment and sprung a leak.....during a night flight.

VFD

23rd Feb 2013, 03:49

Why do all ASTARS seem to end up as a pile of ashes
I do not know but local TV Helo pilot says they are equiped with a 140 gallon plastic fuel tank right under the main gear box rather than a bladder.

His assumption was that a hard landing breaks the gear box and crushes the fuel tank or a hyraulic shock from the fuel in the tank on a hard/crash landing causes the tank to rupture.

This one happened almost in my back yard, literally.
I had an idea from your previous posts that you probably lived pretty close to the accident.

VFD

henra

23rd Feb 2013, 11:23

O2 fires have killed crews before.....

Could be a possibility.
However, it doesn't explain the apparently low energy state of the Rotor system during impact. Looks at least like there must have been other factors involved...

homonculus

23rd Feb 2013, 11:48

Oxygen leaking may support combustion but doesn't cause it. In any case modern medical pipeline systems or simple cylinder supplies don't leak. The O ring seals are only used on anaesthetic machines not aircraft. Provided you check the system daily which is mandatory for patient safety I would put this right at the bottom of the possibilities

SASless

23rd Feb 2013, 11:59

Homo.....that being so....why then have there been aircraft destroyed on the ground while crew members were doing the preflight checks on the O2 systems? I am familiar with several.

Oxygen does not burn....but it sure provides for a hotter, more intense fire should there be an Oxygen enriched atmosphere....as you well know.

There are multiple ways of experiencing a fire in flight but if the report of a cabin fire is correct then it rules out many possible scenario's don't you think?

The 350 amongst its many issues....does seem to wind up in a heap of ashes more often than not.

Medical helicopter crash in Oklahoma City claims 2 flight crew members, injures another | News OK (http://newsok.com/two-dead-in-helicopter-crash-explosion-in-northwest-oklahoma-city/article/3757973)

Helinut

23rd Feb 2013, 14:47

RIP. Very sad. On the barest of initial information, it does not seem to be the "normal" HEMS accident. Given the circumstances, I think it would be unwise to discount oxygen. If you do get enrichment it changes the whole game with fire. Things you would not think of turn into great fuels and innocuous ignition sources leap to start the thing up.

Forensic investigation should give us a clue, the fire spread is likely to be different if O2 is involved.

homonculus

23rd Feb 2013, 15:29

Helinut

Totally agree - oxygen does indeed support combustion. I was just saying it wasn't the cause: ie there must have been another source of fire, but the oxygen may then have acted as an accelerator

SASless

Can't comment without more information. Correct checking of a medical oxygen system does NOT involve release of more than about 4 litres of gas at no more than 1.5 atmospheres. Unless you squirt this at an open flame it won't cause a problem.

Changing old style cylinders does require releasing at high pressure. This should be done away from the airframe before fitting the cylinder. Modern cylinders do not require venting or any release of oxygen

As with helicopters, failure to follow correct procedures with oxygen cylinders can be dangerous

VFD

23rd Feb 2013, 17:03

However, it doesn't explain the apparently low energy state of the Rotor system during impact

If you look at the rotor against the tree there does not appear to be any damage to the rotor blade or significant damage to the other rotor blades.

So unless the craft slid to that position from forward velocity just does not look like the rotor was rotating with any authority.

VFD

Devil 49

23rd Feb 2013, 17:09

"I do not know but local TV Helo pilot says they are equiped with a 140 gallon plastic fuel tank right under the main gear box rather than a bladder."

The Astar fuel tank is a 'plastic' cylinder in the central truss box upon which all the airframe is built. Baggage compartments either side and aft of that box, and the bulkhead between the cabin and other areas is the forward face of the 'box'. O2 is commonly installed in one of the baggage bays and will directly abut the 'box' containing the fuel cell.
The main gear box is attached to the top of the central 'truss box' over the tank.

I am unfamiliar with this accident aircraft configuration, but many O2 installations have a separate pilot controlled master cutoff valve installed at the LOX tank. I respectfully disagree with "Homonculus', O2 leaks can occur, but I believe they are infrequent. The only time I've used the O2 cutoff was after a hot patient unloading with O's left on.

I would be interested in the cabin heat and demist system in situations similar to that described this event.

homonculus

23rd Feb 2013, 19:13

I think we are getting a little off message but

A 350 would only carry a few thousand litres of oxygen in an EMS role. If you have a leak of more than a couple of litres a minute you will very soon put your patient at risk due to inadequate oxygen. If the leak is in the pipeline you will also immediately be unable to provide high flow oxygen again putting the patient at risk. If is happens in a hospital it is a major reportable event. in the UK at least we use hospital standard pipelines in aircraft. Leaving a flow meter turned on with 4 litres a minute running is hardly an issue

A LOX is a totally different system from cylinders. The oxygen is low pressure and liquified. Spillage of high volumes of gaseous oxygen cannot occur because the portable systems vaporisation systems are only capable of 10 to 20 litres a minute. That is why we can't run high consumption equipment such as heart lung machines off LOX. Of course, in a high G impact the actual container can rupture leading to leakage of liquid oxygen. But otherwise it is so safe that we have clearance to carry 50000 litres on commercial flights

There appears no evidence to implicate oxygen in this accident, but having spent many years getting LOX approved by the CAA I am keen to ensure the excellent safety record is not besmirched

Brian Abraham

24th Feb 2013, 04:22

oxygen does indeed support combustion. I was just saying it wasn't the cause: ie there must have been another source of fire, but the oxygen may then have acted as an acceleratorIt could indeed be the cause. Spontaneous combustion is a possibility whenever an organic material is introduced into a 100% oxygen atmosphere.

Know of a case where a surgical patient died as a result of oxygen igniting a (presumably synthetic) stent in the trachea.

There is a very good reason fighter jocks are admonished about wearing lip balm, it typically contains beeswax or carnauba wax, camphor, cetyl alcohol, lanolin, paraffin, and petrolatum. Some have found out the hard way.

It's a worry that those in the medical profession seem to have no/little appreciation of the dangers involved. Advice from a medical site,Here is a quick tip.
If you are having trouble getting a child to tolerate an oxygen mask, or you need to deliver nitrous oxide via a mask, smear a little flavored lip balm into the inside of the mask to provide a *juicy* pleasant smell.

If you purchase a selection of different flavors you can then ask the child to help you decide which flavored oxygen they will get to breathe.A humorous (true) story,A Captain attended a meeting with a burnt face and without his usual well groomed waxed moustache.

"What happened?" he was asked.

"We lost cabin pressure", the captain ex-plained, "so I grabbed the oxygen mask, slammed it to my face and—whoosh! my moustache caught fire"—

Aage Roed, Swedish Board of Accident Investigations.

Gentlemen with waxed moustaches who suffer from decompression should always place a wet napkin over their faces before donning an oxygen mask. Waxed moustaches, perhaps when sparked by static electricity, burn well in oxygen and do not meet FAR125.853 nonflam regulations.

homonculus

24th Feb 2013, 08:14

Adroight

24th Feb 2013, 08:23

http://flightsafety.org/hs/hs_jul_aug99.pdf

John Eacott

24th Feb 2013, 08:38

I accept we don't have a turbine, and if the oxygen store is totally disrupted or the entire operating theatre breaks up then oxygen may accelerate any fire, but oxygen doesn't just catch fire and nor does it leak significantly.

It may be worth reading about an Australian Longranger VH-CHP accident (http://flightsafety.org/hs/hs_jul_aug99.pdf) back in May 1997 where in preparation for the return flight to Rockhampton, the pilot slowly opened the valve on the medical-oxygen cylinder installed in the baggage compartment.

The pilot recalled that, after opening the valve, he was blown violently from the helicopter onto the ground. He received damage to his left lung, internal bruising and a punctured eardrum. The helicopter was destroyed by fire.

The report found that the oxygen system had not been properly cleaned, but essentially it self ignited as a result.

homonculus

24th Feb 2013, 08:41

Thanks Adroight

1997 in Australia. They used a faulty adapter to connect a piece of plastic hose to an old style cylinder. The system was thought to be dirty. No wonder there was a problem. The CAA would not have approved this in the UK in 1987

All UK pipelines in hospitals and I hope helicopters (certainly the ones I have overseen) use a specifically designed braided material that prevents static charges building up, and are lifed and sealed. The pipeline ends in a specifically designed Schroeder probe or is welded to the housing. All connections spring off if not fully engaged and the system self seals

We remove and separate the system from the aircraft for maintenance to avoid any oil or grease coming into contact, and place warning decals to this effect.

I suspect grease had got into the system and the pipeline then failed.

Please note the report states 'oxygen is non flammable but will support combustion'. That is all I am saying.

John - just seen your post. The issue is you do not clean oxygen systems. They are totally sealed so dirt can't get into them. We do take precautions to avoid external dirt. The hose itself has a date on every metre and is replaced when it expires. Oxygen does not self ignite, but when in contact with grease it can explode.

skadi

24th Feb 2013, 08:52

Another one ( happened while checking the O²-system ) some years ago at Stuttgart airport:

Rettungshubschrauber ausgebrannt [ Einsatzbericht / Flughafen Stuttgart ] (http://www.feuerwehr.de/einsatz/berichte/einsatz.php?n=8125)

skadi

John Eacott

24th Feb 2013, 09:01

Brian

As a specialist in difficult airways I am on my home ground when I say there has never been any spontaneous combustion in the trachea as you describe. You are describing a very specialised operation for patients with cancer where we use diathermy or laser to resect the trachea in the presence of a Montgomery tube. The patients are very ill and need enriched oxygen into the lungs. The oxygen can support combustion from the naked flame of the diathermy or the burn of the laser and the tissues then ignite. We simply squirt water from a syringe onto the flame and it goes out. Has happened to me twice.

You simply don't get 100% oxygen is a helicopter cabin. I did the tests in the 1980s. Even with an old style cylinder fully open with doors shut on the ground the cabin O2 concentration was only in the 0.4s.

We use very high flows of oxygen every day in operating theatres where the controlled air changes are far far lower than those in a 350 in flight and where Medical electrical equipment is merely checked for ground leak as opposed to aviation equipment which has to be additionally Checked for flammability and electrical circuit safety. We simply don't get fires.

When we need approval in the uk to mount medical equipment it has to be bench checked for flammability and circuitry (as well as flight tested for interference). Many many items I use in my operating theatre have failed these bench tests. In other words my operating theatre is far more flammable and has far more ignition points and higher concentrations of oxygen. Yet we don't get fires.

I accept we don't have a turbine, and if the oxygen store is totally disrupted or the entire operating theatre breaks up then oxygen may accelerate any fire, but oxygen doesn't just catch fire and nor does it leak significantly.

I have never come across the advice you mention about lip balm in children. It is medically daft. Of course if you add a spark to a petroleum based substance don't be surprised if it ignites, and if there is enriched oxygen the fire will accelerate. That is many I don't smoke while I am refuelling. But in my EMS ship at least we wear nomex and don't have flammable substances. So we don't have a fire in the first instance........we hope

homonculus,

I respect your experience, but I have noticed before that your responses appear somewhat dogmatic and reluctant to listen to the experience of others. I was a bit delayed with my last post and was pipped by Adroight, but you (again) were quite dismissive of the report and the background of the 206L accident. Read it thoroughly and the comments about the fit being to a similar standard as the FAA at the time: how can you be so adamant that the UK wasn't fitting helicopters to a similar standard 16 years ago?

You dismissed Brian's comment about a tracheal fire and death, yet a simple Google search indicates that not only have there been such deaths in the past, but current medical papers on the procedure highlight it as a very real concern. One death (http://www.ncbi.nlm.nih.gov/pubmed/17378792)in 2007 is offered as proof that it can and has happened.

A little more understanding by you would garner lot more respect from your aviation peers.

Brian Abraham

24th Feb 2013, 10:43

homonculus, you seem to dismiss the dangers of oxygen with gay abandon. Organic compounds run the risk of spontaneous combustion in a 100% oxygen environment. End of story, based on the destruction of aircraft and injuries suffered by aircrew. Reread my previous post and the moustache fire. An event that has occurred to more than one fighter jock.

Access forbidden! (http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20080026076_2008025594.pdf)

Thridle Op Des

24th Feb 2013, 11:03

Or this recent one: Certified modern B777, source of fire, FO Emergency Oxy System

http://i197.photobucket.com/albums/aa266/thridleopdes/egypt_b772_su-gdb_cairo_110729_2.jpeg

http://i197.photobucket.com/albums/aa266/thridleopdes/egypt_b772_su-gdb_cairo_110729_1.jpeg

homonculus

24th Feb 2013, 11:10

Thanks John

I fear you have misunderstood my response. I am not at all dismissive of the report. Somebody was injured and if this had happened in flight the consequences would have been worse. The report itself hits the target. I merely highlighted the salient points. The report quite rightly identifies that dirt, and in particular grease, can cause a problem, and that the tubing and connector used were inappropriate.

I indeed do not know what the FAA was mandating at the time, although the fits I was flying in in the USA before this were of a higher standard. I have also been careful not to state that all system in the UK are of an adequate standard - I merely expressed my hope that they were.

What I can be sure of is that from 1987 the CAA has mandated that all medical equipment, including oxygen systems, permanently mounted in aircraft, are of an adequate standard. I wont tell you how I know for fear of being labelled dogmatic!

It is of ongoing concern that many aircraft continue to carry oxygen and medical equipment that is not of this standard on the basis of temporary, carry on, and captains discretion.

As to your reference I am afraid the link clearly states that diathermy was involved. In other words there was a naked flame and an intense heat source. I am sorry to appear pedantic but if you apply a naked flame to a patient's airway when it is contains 100% oxygen we can all accept the result may be a fire. What I do not accept is the extrapolation that oxygen systems simply spontaneously combust. There has to be a source of the fire.

There is no evidence currently that this was a factor in this accident. However day after day my colleagues struggle to provide safe standards of care for critically ill patients who need to be flown. The biggest hurdle after financial restrictions is the argument that it is dangerous; doctors tell us helicopters are dangerous, pilots tell us oxygen is dangerous. If my frustration appears dismissive, I apologise but the report summed it up: 'oxygen is non flammable'. We can carry oxygen safely in aircraft, accepting that if there is a major impact that results in fire that fire may be accelerated by the oxygen. Posts on PPRUNE, oft quoted elsewhere as definitive statements, implying otherwise do need dogmatic replies.

SASless

24th Feb 2013, 11:14

TOD.....Talking about being in the Hot Seat!:uhoh:

homonculus

24th Feb 2013, 12:02

Thridle Op Des

The emergency Ox System according to the report had stainless steel pipelines, plastic tubing with no specification as to conductivity, and the design allowed high pressure oxygen to step down to low pressure in one stage which can cause heating if there is failure. In addition there were electrical components involved and issues over the wiring.

I have no knowledge of these systems, but none of these factors relate to medical gas systems which only use flexible pipelines with specified conductivity and flammability, step down in two stages, and do not have any electrical components.

Medical gas systems in hospitals did have these failings, but a number of fires in the 1950s plus the involvement of several eminent doctors and an enlightened BOC led to standardised systems and hospitals have proven to be safe. Brian Abraham's reference also details military systems using alloys, differing metals and silicone plugs as well as high flow transfers. Again issues the medical systems avoid.

Brian Abraham

24th Feb 2013, 12:15

What I do not accept is the extrapolation that oxygen systems simply spontaneously combust. There has to be a source of the fire.There doesn't have to be an ignition source when organic matter and pure oxygen meet, they combust spontaneously, a fact taught by the military in flight school, and the FAA. The usual triangle of fuel, oxygen and ignition source is reduced to oxygen and fuel.

homonculus

24th Feb 2013, 12:57

Brian Abraham

If as you say when oxygen and organic matter meet they combust spontaneously, why can we give 100% oxygen to patients day after day in safety? Patients are organic matter. Sorry, I just don't follow this

Thridle Op Des

24th Feb 2013, 13:07

Sorry homunculus, I'm with BA and JE on this. Here is another, possibly more famous Oxy event:

http://i197.photobucket.com/albums/aa266/thridleopdes/gpn-2000-001834.jpg

Before you get too excited, in the Egyptair and the NASA events the actual ignition source was never determined with any degree of certainty. If you want another graphic demo of oxygen and grease interaction, look no further than Valujet.

Brian Abraham

24th Feb 2013, 13:53

Patients are organic matterIn chemistry flesh is not considered to be an organic compound, being composed of 75 percent water, 19 percent protein, 2.5 percent intramuscular fat, 1.2 percent carbohydrates and 2.3 percent other soluble non-protein substances.

While there is no "official" definition of an organic compound, an organic compound is generally regarded as a compound with carbon/carbon or carbon/hydrogen bonds. Organic matter typically contains 45-55% carbon, 35-45% oxygen, 3-5% hydrogen and 1-4% nitrogen. The mix of those elements is what makes organic compounds potentially explosive in a 100% oxygen environment.

Flesh will decay into organic compounds, as will vegetation.

homonculus

24th Feb 2013, 14:59

Agreed TOD nothing was proven. Particularly spontaneous combustion! So I wasnt getting at all excited. But issues with electrical wiring were identified. Whether it was a spark in the oxygen system or grease as you allude to, I have no issues. I agree this creates a risk, and if you add a spark or have oil in the system you have a real likelihood of ignition. That is why the medical systems have been designed as closed systems.

I still dont understand your point BS. Are you suggesting we have rotting flesh on board, or vegetation? Even if you did have this, how can it get inside the medical oxygen system??? The oxygen concentrations outside the system, with the exception of about 10cm around the patient's mask or the ventilator exhaust valve, are hardly increased above 21%. A poorly trained mechanic I accept might smear grease accidentally on the outlet or probe. That is why we cap them and remove them. I dont understand where this 'organic compound' comes from, how it gets into a closed oxygen system, and how it creates a risk in a helicopter but doesnt create a risk in an operating theatre or land ambulance. Given how many more land ambulances there are compared to EMS helicopters, and given they are not cleaned or maintained to aviation standards, we would expect to see regular 'spontaneous combustion'. We dont in the UK.

John Eacott

24th Feb 2013, 21:44

For a more in-depth understanding of the Australian Longranger fire, the full ATSB report is here (http://www.atsb.gov.au/media/1539555/aair199701421_001.pdf).

Brian Abraham

24th Feb 2013, 23:10

Are you suggesting we have rotting flesh on board, or vegetation?I don't know whether you are being purposely obtuse. You may wish to visit your dictionary, my Concise Oxford defines organic as,

physiological - of or relating to a bodily organ or organs
medical - (of a disease) affecting the structure of an organ
chemistry - (of a compound etc) containing carbon

So flesh is not an organic compound, and it is ORGANIC COMPOUNDS that we are talking about.

Your failure to understand spontaneous combustion is a worry, given the cases in aviation where it has occurred. A Moderator on these forums, who has a wide background in aviation, posted in one thread "most of us have seen various training films (or demonstrations) wherein an oxygen stream ignites a flammable substance without any external ignition".

You might wish to familiarise yourself with http://www.boconline.co.uk/internet.lg.lg.gbr/en/images/tg-8340-oxygen-v1.3410_39599.pdf Particularly where it says,

May cause or intensify fire
Contact with combustible material may cause fire

The GRINCH

25th Feb 2013, 12:30

First of all, Condolences to the families.

Stepping away from O2

These are just speculations on what the photo shows:
Look at the first photo. Notice the tail stinger is broke and the tail rotor is still attached to the gear box. This most likely happens in a high vertical decent impact with the tail rotor turning slow or not at all. Had the tail rotor been turning at normal speed, it would have broken and catapulted a few yards away. Also the main rotors have very little damage. At 390 RPM, the rotors should have chopped the little tree down. I don't see any cut branches. It's possible it slid there but I don't see any skid marks on the cement. I would think that an impact strong enough to break the stinger off the tail could also rupture the fuel tank which would cause the fire. Hard to tell but it looks like the skid tube is broke on the right side, typical of a very low rotor (retreating blades stall first and, in the case of an Astar, it would roll right.)
Anyone know what direction they were going in relation to where it came to rest?

VFD

25th Feb 2013, 16:04

I would think that an impact strong enough to break the stinger off the tail could also rupture the fuel tank which would cause the fire
Two nurses had egressed from the nursing home and one passerby after hearing the noise from the craft hitting the ground.
So it must have hit the ground pretty hard.
They carried one of the severely injured away before the craft became completely ingulfed in flames. According to the passerby they had trouble putting the fire out on the one survivor's body as he kept reigniting from the fuel soaked clothing. They got no response from the other two.
So you just have to guess it was appox a couple of minutes after impact and respond before the fire had grown enough to force them away.
Doubtful that O2 would have been a cause of the incident.

VFD

con-pilot

25th Feb 2013, 16:24

Anyone know what direction they were going in relation to where it came to rest?

They were west bound until what ever happened, happened to them. The direction that the wreckage is now facing would be north, requiring at least a 90 degree turn to the right.

A relative large airfield was 2.5 miles due south of the accident site, Wiley Post Airport (KPWA). Although Wiley Post is a controlled airport, the tower was closed, it does not open until 06:00.

For those that are seemingly focusing on an O2 fire in the cabin, I would caution you that there is no confirmation that there was a fire in the cabin. Two other witnesses have come forward and neither of them reported seeing such.

fly911

25th Feb 2013, 17:19

Lemishko said witnesses saw a flash of some kind coming from the helicopter before it started to descend.

KOKH FOX 25 :: Top Stories - NTSB Begins Investigation into Deadly EagleMed Crash (http://www.okcfox.com/newsroom/top_stories/videos/kokh_vid_9946.shtml)

con-pilot

25th Feb 2013, 17:29

I am no more saying that there was a fire in the cabin, than I am saying was no fire in the cabin. It is just that this point, it cannot be taken for granted.

Lemishko said witnesses saw a flash of some kind coming from the helicopter before it started to descend. The NTSB is looking into anything that could have caused the a flash to come from the aircraft, but said that the flash is just "one small piece of the puzzle."

In one accident report I studied at the NTSB school, a "flash" was observed coming from the aircraft just prior to impact. The flash turned out to be the strobe light.

Sometimes if one places too much importance on an eyewitness report, other factors can be overlooked. There are eyewitnesses that have not a clue about aircraft, then there are eyewitnesses that are professionals in aviation. Unfortunately usually it is the former that witness the vast majority of aircraft accidents.

Shawn Coyle

25th Feb 2013, 20:27

Even on-board 'witnesses' can be severely wrong. I recall one accident where the lone survivor said 'we must have hit an unlit crane' when every other piece of data (radar, GPS, lack of damage to cranes, lack of damage to airframe and rotors) said there was no crane involved.

Brian Abraham

26th Feb 2013, 00:35

For those that are seemingly focusing on an O2 fire in the cabin, I would caution you that there is no confirmation that there was a fire in the cabinCon, my take on the discussion has been that there has been no suggestion of a fire in the cabin, merely talk of the dangers of the gas and what it is capable of.Sometimes if one places too much importance on an eyewitness reportAnd some of the very worse witnesses are fellow aviators. Remember during an accident investigators course we were shown a film of an aircraft taking off and subsequently crashing, and were asked questions as "expert" witnesses.
Type of aircraft? Answer F-86, Wrong - actually a G91
Cause of accident? Answer engine fire ("smoke" seen throughout take off roll) Wrong - "smoke" was spray from a water drenched runway. And so it went on.

SASless

26th Feb 2013, 06:05

Early on in the thread.....Con Pilot told us local news reports had reported witnesses saying there was a cabin fire....and noted how unreliable such reports can be.

I then brought up the topic of O2 Fires as one possibility for a cabin fire.

If anyone stretched that to being the cause of this crash....that is on them as at this point none of us have any idea what caused this tragedy.

topendtorque

26th Feb 2013, 09:31

Condolences to all.

When getting endorsed on machines there is always something that sticks firmly in the cranium.
In my instance on this type I was sternly administered to, "take care in case of engine fire," and what to do about it quick time with various pointed references to the onboard fire extinguisher, its accessibility and currency date.
. I was berated with, "it has been known to happen more than once". Observe eyes rolled etc.

But of course I am suggesting nothing,

However I did carefully observe thereafter several quite hard fluid and air lines in the upper baggage compartment, quite some with fraying and small leaks as the particular aircraft was close in time to the big tear down inspection.

con-pilot

26th Feb 2013, 17:06

And some of the very worse witnesses are fellow aviators. Remember during an accident investigators course we were shown a film of an aircraft taking off and subsequently crashing, and were asked questions as "expert" witnesses.
Type of aircraft? Answer F-86, Wrong - actually a G91

That is very true, sometimes ever 'expert' witnesses get it wrong. In the NTSB Aircraft Accident investigation school I attended, the class was shown a video. It was a video of an midget aircraft class air race in Reno, Nevada.

We were only told to watch the video, nothing else was said, after watching the video for about three minutes, as the group of racing aircraft entered a pylon turn, a wing came off one of the aircraft. The instructor immediately stopped the video and asked, "Which wing separated from the aircraft?"

Three fourths of the class got it wrong.

Now admittedly the entire class was not composed of pilots, actually very few of the class were pilots, but all were aviation professionals. As it turned out, I was the only pilot that got the correct wing the first time.

The point I was attempting to make is, if an accident was witnessed by a school teacher, a policeman and an active professional pilot with years of experience, the testimony of the professional pilot would be given a little more credit. Never the less, all three statements would be investigated.

Oh, believe it nor not, the pilot survived the accident.

Matari

17th Mar 2013, 03:31

From the preliminary report:

A person who was driving in the vicinity of the accident site reported that he distinctly observed a "flash" in the sky in front of him. After the flash, he saw the helicopter in an increasingly rapid descent before it disappeared behind buildings. He then drove toward an area where smoke was emanating and saw that the helicopter was on fire in the parking lot of St. Ann’s. He immediately assisted others (St. Ann’s employees) in pulling the surviving paramedic away from the burning aircraft.

Fixed video surveillance cameras located on a building adjacent to the parking lot showed the last few seconds of the helicopter descending toward the ground. The video showed that the helicopter burst into flames upon impact. From the initial impact point, the debris path was approximately 75 feet in length, on a heading of 065 degrees magnetic. All of the impact signatures were consistent with a right side low (approximate 40 degree) attitude, with a high rate of descent. Using the geometry of impact signatures and adjacent structures clearance, the helicopter’s angle of descent was approximately 25 degrees.

http://dms.ntsb.gov/aviation/AccidentReports/tlg5fja1bmr4csu1d3mmtwu31/J03162013120000.pdf