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-   -   DASH 8 accident in PNG (https://www.pprune.org/australia-new-zealand-pacific/466192-dash-8-accident-png.html)

Aerodynamisist 16th Oct 2011 09:22

Bad fuel ? isn't it standard procedure to quarantine fuel from the departure/refuel point in cases such as this ?

Cravenmorehead 16th Oct 2011 10:46

They did immediately. Not sure about now.

my oleo is extended 16th Oct 2011 11:29

My sources tell me there were doubts about fuel quality in Lae several weeks before this accident.
Doesn't mean that fuel contamination is the cause, but the fuel facility was quarantined after the crash......Time will tell.

sheppey 16th Oct 2011 12:22

There were media reports that witnesses said a violent storm was in progress at the time of the accident. Was the storm in the approach path?

blackhand 17th Oct 2011 01:36


My sources tell me there were doubts about fuel quality in Lae several weeks before this accident.
Is this true? There is only drum stock at Lae, used by helicopter operator, Dash8 has great short field capability but cannot hover.It is important that RUMOUR has some truth in it. Nadzab is the airstrip used by fixed wing.
Surely the several operators refueling with AVTUR at Nadzab would have known of this. APNG would not use "suspect" fuel and would have flight planned accordingly.


Was the storm in the approach path?
Would a pilot with so much expeience in PNG operations elect to do a letdown through a voilent storm?
And to all at APNG, be of strong heart.
BH

dhavillandpilot 17th Oct 2011 05:31

Can anyone tell, Capt Bill Spencer, is also an engineer? I remember a Bill Spencer who use to work at Camden in the 1980's.

Not morbid curosity but more keeping track with past aquaintances and fellow airmen

VolLibre 17th Oct 2011 07:52

Mechanical fault suspected
 
From Radio New Zealand International


But the first secretary to the Minister for Civil Aviation, Levai Wama, says it already looks like there was a mechanical fault on the plane.
“Based on the information that the pilot gave to the towers which was there’s smoke coming out of the engines and we’re running out of power, doing a forced landing, that’s what they said, which resulted in it crash landing.”
Levai Wama says a team from Canada representing the airframe manufacturers and engine makers are doing their own investigations.
PNG crash: Pilot saw smoke, attempted emergency landing

BBN RADAR 18th Oct 2011 02:23

Bad fuel is no longer a suspect:


PNG Accident Investigation Commission chief executive officer David Inau also ruled out the contamination theory put forward by a Lae businessman which The Australian newspaper reported at the weekend.

Diezmann said the bad fuel theory was ruled out because another 15 aircraft also refuelled at Nadzab Airport, Lae, from the same batch of aviation fuel last Thursday.
He said initial testing and analysis of the fuel confirmed that the fuel supplied to the aircraft in Lae fully complied with specifications.
Diezmann said comprehensive testing has now been completed by a specialist independent laboratory and consequently CASA had cleared the company’s refuelling operations.
I'm very disappointed with the Australian for running with that story. What sort of authority did this Lae businessman have on the matter? They didn't think about that and just decided to take a punt and go with it... shoddy journalism.

@ dhavillandpilot, Bill Spencer has never been an engineer. He was flying for Air Niugini all through the 80s.

Ejector 19th Oct 2011 06:24

I agree, shoddy reporting on steroids.

I am sure there are some very experienced & smart people involved with this investigation, that will work out what happened. Lets wait for them to do their job.

KRUSTY 34 19th Oct 2011 10:33

You're not thinking of Bill Cooper are you dhavillandpilot? I think he was at Camden during the 80's, also taught at Sydney Tech during the same period.

TunaBum 19th Oct 2011 22:57

For Info:

http://rgl.faa.gov/Regulatory_and_Gu...2005-13-35.pdf

TB

Kiwiconehead 20th Oct 2011 03:34

Dash 8 has triggers under each power lever that must be lifted to move below flight idle gate.

There are 3 options with regard to prevention of beta operation in flight.

The AD above refers to the beta lockout mechanism which prevents the movement below flight idle in flight. This is only mandatory for FAA certified aircraft - not in Australasia

There is also an option of just a beta warning horn which sounds a warning siren if the triggers are lifted.

Third option is none of the above.

TunaBum 20th Oct 2011 03:57

Kiwiconehead,

So the power levers can not be moved below the flight idle gate in flight, without lifting the triggers and the siren sounding?

Are the "triggers" and the "beta lockout mechanism" one and the same thing?

TB :confused:

blackhand 20th Oct 2011 04:21


This is only mandatory for FAA certified aircraft - not in Australasia
Country of origin AD/s are MANDATORY in PNG and Australia,

cnic 20th Oct 2011 04:27

This is a Canadian produced airframe not USA. Thus the FAA have no authority for this mod. This is Transport Canada's baby thus why they have sent people to png.

Kiwiconehead 20th Oct 2011 06:37


So the power levers can not be moved below the flight idle gate in flight, without lifting the triggers and the siren sounding?
The power levers cannot be moved below flight idle at any time on air or ground without lifting the triggers.

If the beta warning system or beta lockout system is fitted a siren will sound when either trigger is lifted with weight off wheels and above 20ft radalt


Are the "triggers" and the "beta lockout mechanism" one and the same thing?
No.

"beta lockout mechanism" is not a great description. Comes from the AD requiring a "mechanism: , ie a way to, to prevent operation in beta in flight.

It is actually an electrical circuit which will activate to coarsen the blade pitch when low blade angle ( = high rpm) is detected. It works by actuating the feather solenoid to cause the prop to move toward feather, when blade angle has coarsened the required amount the solenoid deactuates and the blade will move fine again triggering the beta function again so it will move coarse/fine/coarse/fine in a small range. The ground range lights for the respective engine will be cycling at this stage on the pilots glareshield.

I'm not that familiar with beta lockout as of the 40 odd dash 8s i've worked on over the years, i've only seen one with it fitted, like i said, not mandatory in Australasia - although maybe not for much longer.


BTW - all this above is how the system works on a serviceable aircraft.

I'm not postulating any whys with relation to the accident, I don't even know which option was fitted, if any.

TunaBum 20th Oct 2011 08:27

Thanks Kiwiconehead,

Very informative.

It will be interesting to if any of this is relevant once the proper investigations are completed.....

TB

blackhand 20th Oct 2011 11:59

@kiwiconehead
Yes, thanks for the explanation.
Are you able to tell me:
When are the throttles retarded to the beta gate during flight?
Is there a secondary prop OS governer like on King Air?

BH

Jabawocky 21st Oct 2011 01:25

Not sure if this is 100% correct although it came from a reliable colleague of the Captain, but they had a prop overspeed on one engine, and while securing that the other flamed out. Tried to relight but heights and speeds conspired against them and the ditching followed.

No doubt there are a lot more details, and perhaps this is not quite accurate, but a slightly different version of events to contemplate.

blackhand 21st Oct 2011 22:33

‘Over speed’ may have caused crash

By GEOFFREY THOMAS
Aviation Editor
The West.com.au

Investigators are focusing on possible component failure for the loss of both engines on the Dash 8-102 which crashed while approaching Madang on October 13, killing 28 passengers.
The Airlines PNG plane was on a flight from Lae to Madang with 32 passengers and crew and there were only four survivors including the Australian captain and New Zealand first officer.
According to a source in Australia, investigators are looking at the possibility that the plane’s propellers went into an over-speed condition, causing the engines to fail, because of an alleged failure of a restricting gate for the throttles when they are put into idle. The engines apparently failed soon after the pilots started their descent.
According to the source there was a previous similar failure in 2006 involving Wideroe Airline in Norway, although only one engine stopped delivering power.
Captain Bill Spencer (64), who was flying the Airlines PNG plane, was one of the airline’s most experienced pilots, with 35 years in New Guinea and 18,000 hours flying experience, while First Officer Campbell Wagstaff had more than 2500 hours flying experience.
The Australian Transport Safety Bureau has examined the flight data recorder and cockpit voice recorder and has apparently found that there were no maintenance issues with the plane and determined that weather was not a factor. The ATSB has also found no fault with the pilots.
The mechanical or component failure has been alluded to by New Guinea’s first secretary to the Minister for Civil Aviation, Levai Wama.
“Based on the information that the pilot gave to the towers which was there’s smoke coming out of the engines and we’re running out of power doing a forced landing, that’s what they said, which resulted in it crash landing,” Mr Wama said.
However the fact that both engines failed points to the over-speed theory.
Comment is being sought from Bombardier the manufacturer of the plane.
Airlines PNG declined to comment.


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