DASH 8 accident in PNG

[Square Bear]

Reading the report,the Captain had been sick,the F/O had been called off reserve,the aircraft was not fully serviceable,flight controls not fully operational and no auto pilot;it had apparently been U/S for a number of days,
Don't call it pilot error,call it management error.

Not being an apologist for the Airlines management at all, but really, some of your points need looking at.

The report stated that the Captain HAD previously been sick, but reported as fit for the duty. No where does it indicate he was dragged out of a sick bed!! Don't you think that it was possible that he was no longer sick and that is why he went to work that day.

The F/O was called in from RESERVE. Actually that is why pilots are rostered on Reserve. In many, many airlines it is a bonus NOT to be called out on RESERVE

There was no Auto Pilot available due to the unserviceable Yaw Damper. I personally don't think it a smart idea at all flying an aircraft such as this in these circumstances without the help of an autopilot, but that is what the REGULATOR (and obviously the manufacturer) allowed, and allowed for it to up to 10 days.

The other MEL's were not so serious, and I whilst in the perfect world would not be carried, it is not perfect and again both the Regulator and Manufacturer allowed the MEL. So whilst the aircraft may not have been "fully serviceable" it was still legal.

There are a probably a lot of hands that are involved in this tragic event, but it is pointless putting the blame on one identity using normal (and perfectly legal) events to support your argument.

[JammedStab]

Don't call it pilot error,call it management error.

Any pilot flying with these engines should know that you should keep your fingers well clear of the triggers whenever in the air. It is clearly written in the manuals about selection of power levers below flight idle in flight being prohibited.

There have been several cases of accidents happening for similar reasons and there is usually a common theme. The pilot was higher or faster than he wanted to be and somehow the two actions of pulling those triggers and then moving the power levers aft happened.

One has to wonder how much of a random coincidence it is that almost every time if not every time the triggers have been activated flowed by power lever movement aft beyond flight idle in the air leading to an accident, it just happened to be when the pilot really wanted to go down or slow down.

[Hugh Jarse]

Jammedstab,

I'm not going to comment on the crew actions, but in response to the second paragraph of your last post I have to say that with the Dash 1 to 300, it's common knowledge among its pilots that "if you can see it, you can land on it". By that, I mean that if your landing runway is in view, any combination of flight idle, condition levers max, gear and flap will get you safely (and stable) to your proposed touchdown point without exception.

In over 6000hrs on the Dash, I never had to go around because of being too high/fast. The aeroplane is just so versatile and easy enough to fly to enable a stable approach in many unusual situations.

[John Citizen]

One has to wonder how much of a random coincidence it is that almost every time if not every time the triggers have been activated in the air leading to an accident, it just happened to be when the pilot really wanted to go down or slow down.

Is this a common bush technique which works well in other turboprops (Twin Otter) but not so well in a Dash 8 ?

I am just wondering if the captain was using the "crack it into Beta" technique as it always worked so well in other types (if it ever did).

Has anyone heard of pilots successfully using this technique on another aircraft type (or even used the technique themself) ?

[poncho73]

The bush technique of “cracking it into Beta” is not an approved method of operation in any of the Twin Otter, Dash 7 or Dash 8’s.The Dash 8 propeller is governed as far back as 2/3’s of the way between Flt Idle and DISCing, but unlike the PT6 controls, beyond that point, props are no longer governed and have what is referred to as ‘positive reverse’ in the PW100 series of engine/prop controls. At lower speeds during approach, there is insufficient airflow to drive the prop to overspeed. Reading between the lines of your (John Citizen’s) comments, is it possible that this particular pilot had used Beta without adverse effect on prior occasions, but didn’t know that the high speed characteristics of the prop were disastrous at Vmo?

[swh]

poncho73

I dont think people realise you can be in beta RANGE without selecting reverse, they are not the same animal.

I think every person who has flown a PT6 powered aircraft has been in Beta RANGE totally legally. Beta RANGE is when the prop speed is controlled by the power lever, i.e. taxi, and often on final approach. Beta range is not the same as reverse range, however the reverse range can also be considered in the beta range.

Alfa RANGE is when the prop levers control blade angle.

I do not agree with your comments about "bush technique of “cracking it into Beta” is not an approved method of operation in any of the Twin Otter" as the aircraft is in flight idle". It happens every day, totally legal.

Sorry to digress, please continue.

[poncho73]

Good point swh, I got excited when composing that response and forgot to include the word "GROUND" Beta. You are correct Beta is used in the air. I should also say....nothing below Flight Idle detent (considered GROUND Beta) is permitted while airborne, including the Twin Otter, it is not "legal" as you say to operate in this regime. I hope this does not happen everyday as you say, but I would like to continue the discussion.

[Paragraph377]

APNG delay Annual Report

Have APNG sought an extension so that they can put some spin and waffle together to counteract the damning Dash 8 accident report? Of course they will. It is interesting how over the past 3 Annual reports the Chairman and Director have filled the report with page after page of financial jargon, and even financial risk, but there is virtually no statement about safety, commitment to safety, or a prioritisation of safety. No surprise really when you look back at around 9 crashes and 100 dead.
How do some people sleep at night???

http://www.apng.com/News.aspx

POMSOX ANNOUNCEMENT - 18TH JUNE 2014 - EXTENSIONS OF DATES FOR DISTRIBUTION OF 2013 ANNUAL REPORT, PREPARATION 2013 FINANCIAL STATEMENTS AND HOLDING 2014 GENERAL MEETING OF SHAREHOLDERS

Airlines of Papua New Guinea Limited (POMSoX: CGA) advises that:

a) the Registrar of Companies has granted extensions of the dates by or on which the company is to hold its annual general meeting of shareholders, prepare and /or finalise statements for 2013 and to prepare its annual report for 2013 to 29 August 2014; and

b)POMSoX has granted an extension of time to dispatch annual reports to shareholder as prescribed by Listing Rule 4.6 to 30 June 2014.

For further information contact:
Media Relations: Telephone: [phone] Email: [email protected]
Investor Relations: Telephone: [phone] Email: [email protected]

Let the spin begin.

[JammedStab]

Originally Posted by John Citizen

Is this a common bush technique which works well in other turboprops (Twin Otter) but not so well in a Dash 8 ?

I was told to never even think about twisting the grips to go past the low pitch stops in the Twin Otter in flight. I only heard rumour that someone had tried it and there was a loss of aircraft control more to do with aerodynamics of airflow, perhaps over the tail. Perhaps right in the flare, this procedure might get done on offstrip landings.

Originally Posted by swh

I dont think people realise you can be in beta RANGE without selecting reverse, they are not the same animal.

I think every person who has flown a PT6 powered aircraft has been in Beta RANGE totally legally. Beta RANGE is when the prop speed is controlled by the power lever, i.e. taxi, and often on final approach. Beta range is not the same as reverse range, however the reverse range can also be considered in the beta range.

Alfa RANGE is when the prop levers control blade angle.

Correct,

At the finer pitch range at low power settings, the aircraft is in what is known as Approach Beta which simply means that Power lever movement is controlling blade angle. It could be from 10-17 degrees blade angle but I don't have the manual handy at the moment.

Originally Posted by Hugh Jarse

I'm not going to comment on the crew actions, but in response to the second paragraph of your last post I have to say that with the Dash 1 to 300, it's common knowledge among its pilots that "if you can see it, you can land on it". By that, I mean that if your landing runway is in view, any combination of flight idle, condition levers max, gear and flap will get you safely (and stable) to your proposed touchdown point without exception.

In over 6000hrs on the Dash, I never had to go around because of being too high/fast. The aeroplane is just so versatile and easy enough to fly to enable a stable approach in many unusual situations.

Thinking about it now, the accidents that I can remember off the top of my head were on the Fokker 50 and Saab 340 which has a GE engine. I flew the ATR and it seems similar in being able to get down quickly with those prop blades at flight idle.

In this accident, it appears that the scenario was different with a desire to get below a CB cloud combined with an overspeed.

[saabsforever]

F50, S340.

The F50 has the same engine family as the Dash and ATR.
The Saab 340 has GE engines and with 200kt gear speed and 175 flap speed will get down and slow down much better than a Dash.
Interesting to note though that it had the same issue with double engine failure if the power levers were brought back below flight idle at high speed. One in the states deadsticked into an airfield below them at night and got away with it.
The first remedy was a physical block to prevent the levers coming back and later an electronic remedy.Both solved the problem at least they did something real not just putting a sticker on the panel.
Notes on both the F50 and Saabs are buried deep in the accident report.

[JammedStab]

Originally Posted by Ret Sabala

what has to be asked is why? Why did a pilot with around 17,000 hours make such a silly mistake?

I did notice that the pilot only had 500 hours on type. Was he a jet guy that moved into the turboprop world and not particularly knowledgeable about them? Perhaps he had seen, as many have, the Pilatus Porter doing its thing straight down using beta inflight with a PT-6 and assumed the similar was possible with any free turbine engine.

Just a theory but someone could think that the warning not to do such a thing is more of an aerodynamic/high sink rate risk than a risk to destroying engines. I only knew about the real reason for the dangers by reading accident reports in which the same thing has happened.

[Cactusjack]

PX has had accidents and its also unprofitable. It relies on AusAid to keep going. Its no better then apng in a lot of ways

Are you serious? To compare PX accident rate to that of APNG is ludicrous. There is no comparison.

[Gemini Twin]

The outcome may have been different if they hadn't exceeded Vmo, the correction of which lead to the fatal chain of events.

[poncho73]

Doing this at an airspeed of say 160kts or greater in the DHC-8 (1 - 3 series),without Beta Lockout protection, would have resulted in the same propeller overspeed condition. This is why aft of flight idle is prohibited at anytime while airborne, it's just something you never want to try.

[Gemini Twin]

Agreed poncho but at slower speed the air forces may not have "wound it up" so fast. The rapid acceleration and huge increase in noise seems to have caused a huge element of surprise which could not be figured out, i.e. "what have we done", until it was too late.

[poncho73]

That is what the report is saying, although wx might have been an issue:"When the propeller overspeeds occurred, the aircraft was at 10,090 ft AMSL 34 km south south east of Madang aerodrome. If we estimate it might have travelled two nautical miles towards Madang while losing 2,500 ft during the time the flight crew executed the emergency procedures and configured the aircraft to fly at 1.3 VS, it would have been approximately 17 nautical miles or approximately 31.5 km from Madang aerodrome by 7,500 ft AMSL. Prompt execution of the applicable emergency procedures would therefore have probably allowed the flight crew to glide to, or close to, Madang aerodrome. However, the flight crew could not see Madang and were also aware of a storm in the vicinity of the aerodrome."

[ResumeOwnNav]

The Finisterre Arrival is just over 5 degrees FPA.

In a Dash 8 100 it is done comfortably at flight idle, 900 RPM, with 1,600 ft/min RoD between 160-170 KIAS.

Constant descent profile from LSALT 15,000' down to MDA of 850'.

IAF 17 DME, FAF 10 DME.

[Hugh Jarse]

The Finisterre Arrival is just over 5 degrees FPA.

In a Dash 8 100 it is done comfortably at flight idle, 900 RPM, with 1,600 ft/min RoD between 160-170 KIAS.

Constant descent profile from LSALT 15,000' down to MDA of 850'.

IAF 17 DME, FAF 10 DME.

Do you know what the performance of the aircraft would be with one or both propellors overspeeding, or in a combination of overspeed and feather?

At 900RPM and flight idle the PW120 is still providing forward thrust.

I suspect the crew would have been more concerned with controlling the aircraft...

[Ret Sabala]

I personally can't wait for the annual report to be delivered on Monday I think? It should be hilarious.

[Paragraph377]

I personally can't wait for the annual report to be delivered on Monday I think? It should be hilarious.

Maybe so, but of more importance than the humorous AG report bull**** will be the look on managements face if they are ever held to account over this accident. It probably won't happen, considering this mob have had close to a dozen crashes with 100 lives lost and still senior people remain enthroned.
Not even the most robust accident investigation report is complete until the root cause and contributing factors have been addressed, and as with this accident accountability heaped upon the accountable managers.

I just hope the lawyers are lined up over this, the families of the deceased are ready to take this airline to task, those accountable are locked up, the airlines insurance company pays dearly, and the CAA remain glued to this mob until such a day that the crashes and deaths are no longer a common theme. Here's to wishing.