EC225 crash near Bergen, Norway April 2016 [Archive] - Page 2

DeltaV

2nd May 2016, 07:01

The drawing, and photos in posts 200 & 212, show the transmission attaching rods, as they are installed. These rods show a connection from the top deck of the fuselage to the upper case of the transmission. They show that the eye end of the rod attaches to the transmission, while the fork end attaches to the deck.

If the photo of the rotor with the rod projecting up were showing us a disconnected transmission rod, the disconnection has happened at the transmission, because that's the end with the eye? If the rod had disconnected at the deck, we'd be seeing the fork end in the photo, if it were that rod?

My interpretation of that view of the rod is that it is the fork end not the eye end, and that it looks a bit like the eye is due to the POV of the photograph. Were it the eye, I think there would be (a) more pronounced shaping apparent where the cylinder is machined to a flat, and (b) some indication of 'polishing' where the eye mated with the fork on the transmission case.
Not saying this rod has, but very often these eye ends have a spherical bearing in there too.

No speculation as to what happened on my part, just considering what appears to me in the photos.

None from me either.

dipperm0

2nd May 2016, 07:09

Here is an extract of a 532 maintanance manual showing the way the suspension bar are attached on the fuselage fairing.

Pablo332

2nd May 2016, 07:11

The rod end in the picture is a side view of the fork end, probably complete with attaching hardware. The end with the bearing is most likely still attached to the mast.

From the IPC picture above it would appear to be the LH suspension bar.

Innit

2nd May 2016, 07:20

Information Notice 3032-I-00 issued on 1st May 2016 covers the 332 and 532
Is this available online anywhere?

dipperm0

2nd May 2016, 07:24

Hope the picture I posted in post 275 is clear for you.

What can be said from this picture is that on the norwegian crash picture neither the head of the pin, with two flat cuts nor the two safety pins are visible.

The question then is why ?

Gone as a result of the MGB explosion : possible
Gone as a result of a maintenance flaw : possible

Just one thing: the pin are tight fit, with no play in the vertical (lift) axis, they are not rotating parts, thus, I think that a lack of safety pin would not be noticed by a vibration monitoring system.

helicrazi

2nd May 2016, 07:32

Maybe its by parts that were left in the hangar?

REDHANDED

2nd May 2016, 07:47

why am i becoming less and less inclined to trust the manufacturers......

What-ho Squiffy!

2nd May 2016, 07:49

Airliners crash relatively often, and airlines do not normally ground the machines. BUT, if an A380 had its wings fall off on short final to Heathrow, killing 450 people...you'd probably see a grounding. Offshore is a business-to-business operation, with the passengers highly organised and unionised. AIRBUS have not issued a grounding, which means nothing. If the offshore companies/pax don't want to travel in the EC225, then the machine will not be used for offshore. End of story. Bring me another helicopter, Mr CHC.

birmingham

2nd May 2016, 07:50

The two Safety Information Notices regarding this accident issued by Airbus was distributed to operators of 332's and 225's, military and civil.

The first one carries no formal instruction to ground the aircraft. All it does is inform readers of the accident and "allies" Airbus with the decision to put all commercial 225 flights on hold. This cannot be construed as a technical grounding of the aircraft by Airbus.

The second SIN really says nothing more of any significance. My interpretation of it is that Airbus have so far found nothing which gives them any reason to suspend the Type Certificate of the aircraft for technical reasons but they "continue to stand by the decision of the Norwegian and UK authorities to put commercial EC225 flights on hold"

Over the last five years or so, there has been a subtle change in the oil and gas industry to move towards the military practice of grounding an aircraft type after an unexplained accident until such time the cause has been established and "cured". Civilian practice had always been (and still is in the fixed wing world) not to ground an aircraft until evidence has been found that there is an intrinsic airworthiness defect which is likely to affect other serial numbers of the same product.

Imagine the chaos in the air travel industry if Boing 737s were all grounded every time there was a fatal accident involving that type. It is only because of the high profile of the North Sea that the 225's have been grounded. Had this tragic accident happened to a EC 725 (a military version of the EC225) in Outer Mongolia, the North Sea 225s would still be flying.

Another consideration to take into account is the Contract conditions between the helicopter operator and the Oil & Gas customers. I suspect that if there is a mandatory grounding of the helicopter, the Customer may still be required to continue to pay any monthly standing charge. It is therefore in the helicopter operators' interest to persuade their aviation authority to ground the aircraft under these circumstances before the Customer has a chance to suspend the contract.

Irrespective of my thoughts on grounding protocols described above, my innermost thoughts are with the families of the deceased and those in the industry who have to deal with and live through the aftermath of this tragic accident. Very difficult times for you all.

The two aviation authorities need to follow a formal process and to back up their statements with technical evidence. This takes time. What Airbus seem to be saying is that addional data gathered after the crash points to the fact that it is not a repeat of earlier incidents and that this helicopter is safe to fly. They must be feel that the Norwegian and UK authorities will ultimately reach the same conclusion. It would be a very bold statement to put out if they didn't believe they knew the precise cause of the accident.

Pablo332

2nd May 2016, 08:07

tigerfish

2nd May 2016, 08:34

What is the status of the RAF's new (ish) Puma 2?

Tigerfish

BTC8183

2nd May 2016, 08:42

What is the status of the RAF's new (ish) Puma 2?

Tigerfish

😂 New !... 50 yr old sa330 variant.

Impress to inflate

2nd May 2016, 08:58

MoodyMan, I'm afraid that information isn't in the public forum outside OPEC countries for obvious reason, oil and gas companies don't like to publish the costs of commissioning new oil fields. My data comes from a very senior oil company executive who told me the extraordinary cost are incurred in this part of the world, mostly down to the distances involved, very high labour costs and remoteness of the fields as well as lack of infrastructure in the new fields being developed.

thelearner

2nd May 2016, 09:48

The UK is one of the highest production cost areas in the world, and when you talk about cost per bbl, obviously mature fields with low production, this rate increases. There are huge differences in costs, field by field.

This page does not include UK (http://knoema.com/vyronoe/cost-of-oil-production-by-country), but shows breakeven price which includes oil producer government spending which is highly reliant on oil, UK is not.

This page gives cost of producing and production per day. (http://knoema.com/rqaebad/cost-of-producing-a-barrel-of-crude-oil-by-country)

I think there is a lot of truth in both what SLF3 says and Mitchaa, and this is really not the place to be debating this, but in my opinion to have a successful and continuing North Sea everyone needs to work together to make it sustainable for as long as possible to protect jobs.

I have been working offshore since early eighties, but my last chopper flight was over 2 years ago, and I flew mainly in the Puma family from Mk1 to EC225, and my son now flies in the 225 (which is a huge worry for me). However, the pilots on here are spending much more time in them than the workforce (and therefore more at risk).

There have been huge safety improvements on the platforms in my time, and a lot of effort now goes on asset integrity, and detection and shutdown systems, safety case, MAH prevention etc, but in recent years we have been losing people in helicopter accidents, at an alarming rate. Even the ditchings, we got lucky with the weather conditions. I don't think it's only North Sea where we have been losing people in helicopters.

Since Friday my thoughts have been with the families of those lost, and for the lost, I can only remember that joyous feeling when you see land in the inbound flight and are so looking forward to seeing the family again. I hoped their end would be sudden, but sadly it seems they maybe had an awful last 10 seconds.

With the grounding, please lets hope we have spare capacity on other types, and we don't stretch the other types and those that fly them to the limit also.

helimutt

2nd May 2016, 10:05

CHC sending 139's to ABZ to cover shortfall. Rumour has it anyway. Wonder if they'll be asking any of the recently made redundant workforce to help.

tigerfish

2nd May 2016, 10:43

BTC8183 Agreed that the original airframe is very old, - but I'm sure you know that in recent years they were all reworked using much more recent engines and transmissions etc etc. So to all intents & purposes they are much more akin to the EC225. They are now a totally different aircraft from the old SA330.
Accumulation of flight hours will be much less than the commercial variants, but the type of manoeuvres will create more strain I suspect.
I am interested because a member of my family flies in one regularly.
Tigerfish

BTC8183

2nd May 2016, 11:32

tigerfish

2nd May 2016, 11:35

Thanks, - That is what I wanted to hear!
TF

offtrack

2nd May 2016, 11:51

Pablo332

2nd May 2016, 11:56

I’m glad it’s not just me that can see the hardware.

Outwest

2nd May 2016, 12:38

So I will ask for speculation again. If Airbus seems so certain that this was not a manufactures fault, then as most seem to agree here, it must be a maintenance issue, what error on the part of maintenance would cause such a sudden catastrophic failure?

We assume since there was no PAN or Mayday call that this took the crew completely by surprise. So no loss of oil, no chips, no vibrations or strange sounds. I can't imagine what single error ( missing bolt, nut, TQ value ,etc) could account for this, especially since this was not a new MGB replacement, so something done during regular running maintenance.

TwoStep

2nd May 2016, 13:06

I am told that part of decision to lift the operational halt is because inspections have shown there is no connection to the bevel gear vertical shaft issues.

Harry the Hun

2nd May 2016, 13:10

A fill-up with the wrong oil/lubricant?

Outwest

2nd May 2016, 13:13

I am told that part of decision to lift the operational halt is because inspections have shown there is no connection to the bevel gear vertical shaft issues.

Well that seems premature then as that issue caused the oil pumps not to be driven, not the rotor head departing. And again, any oil/lube issue would be preceded by numerous cockpit indications I would think.

roundwego

2nd May 2016, 13:39

I am told that part of decision to lift the operational halt is because inspections have shown there is no connection to the bevel gear vertical shaft issues.
Since when has the CAA (UK & Norway) lifted the ban on EC225 public transport flights? As far as I can see UK CAA Safety Directive 2016/001 and Norwegian CAA Safety Directive 16/05616-1 are still in force as I write this.

Airbus never in fact grounded the aircraft. All they did was their usual pussyfooting around and issued a Safety INFORMATION Notice which indicated that AB "allied" themselves to the CAA directives which of course only applied to UK and Norway. I would be interested to see if all other national authorities other than UK and Norway have grounded aircraft under their jurisdiction.

500guy

2nd May 2016, 14:16

"It's my understanding HUMS picked up on the EC225 bevel failure in advance but due to the once per day download pattern used by the operator at that time, it went out on its afternoon flight and subsequently failed resulting in the ditch. Had the HUMS card been downloaded after its morning flight and before its afternoon flight, the impending failure was clear and would have been caught, the aircraft would never have departed. That's why the industry changed to more frequent after flight HUMS downloads in the aftermath.

If it's a gearbox failure this time around which to be honest, is more probable than probably not, I would expect the HUMS to come under close scrutiny. The difficulty the operators have is deciphering the data and what it actually means to the airworthiness of the helicopter, there are a lot of instrumentation defects for example so these need to be filtered out and it can be difficult to detect genuine mechanical failure modes. HUMS probably catches a lot that we are all unaware of because they get to it in time, it's only when failures happen, HUMS comes under scrutiny. "

It seems to me that for HUMS to truly be effective it needs built in learning software and immediate, internal analysis. i.e. Install it with a manufactured baseline data (expectation of vibrations for a particular aircraft type). Perform a few flights in the learn mode (gathering data about that specific airframe) review the data for those flights to make sure it isn't "learning" any vibrations that are of concern.

From that point on if it detects a vibration outside the standard deviation it could illuminate a light (similar to a chip light). On more complex systems it could even indicate where the vibration is on the display.

I believe all of the technology exists. How far are we away from something like this?

Outwest

2nd May 2016, 14:20

Outwest, I can't think of anything at all maintenance wise that would cause a sudden detachment of the Main Rotor Mast.

Ok, well that makes at least 2 of us....so that statement from Airbus should be taken with a large dose of salt I think....

Oh, and to answer your question, no I would not be strapping one on at this point.

Outwest

2nd May 2016, 14:33

i.e they have no reason to ground the fleet as they don't have any evidence to support that grounding.

That makes me think of the time I asked one of the Indian pilots in Bombay how the Mil 8's were going offshore without flotation....he said well how do you know it won't float, they have never sunk one.

Pablo332

2nd May 2016, 14:44

jimf671

2nd May 2016, 14:44

... ...
AW189 - ...the two of bristow was park and he don't use it (a sheat) ...

Not any more.

Outwest

2nd May 2016, 14:48

Lack of lubrication to the mast bearings may be an issue, I believe on this model there is no way of verifying oil supply as there was on the 332

Again, not a 225 guy, but would that not at least lead to high oil temp, chips or some indication?

Lonewolf_50

2nd May 2016, 14:53

From the underslung MRH picture post 207, it would appear that the MGB Flared housing is missing from the Lift housing of the MRH shaft. Lack of lubrication to the mast bearings may be an issue, I believe on this model there is no way of verifying oil supply as there was on the 332 post MRH replacement. But HUMS should have picked this up. Pablo, are you referring to the upper bearing where the mast comes through the top of the housing? Unfamiliar with this aircraft, but I think I understand that there are oil jets that keep lube coming to that bearing. If the lube doesn't get there, how does a rising temperature get detected? (I think I see your point on an impending bearing failure being picked up by a HUMS sensor).

500guy

2nd May 2016, 14:54

Mitchaa,
Thank you for that detailed answer. I understand it is a steep hill to climb, but at the end of the day its just 2 variables, freq, and amplitude. Computers excel at matching patterns. There would be a lot of parameters to learn (storms, etc as you mention) and a lot of people against it because it would cost some jobs, but at the end of the day, it would be pretty amazing.

crunchingnumbers

2nd May 2016, 15:10

A sad thread indeed but this was funny:

That makes me think of the time I asked one of the Indian pilots in Bombay how the Mil 8's were going offshore without flotation....he said well how do you know it won't float, they have never sunk one.

Satcomm

2nd May 2016, 15:44

500 guy,

As Mitchaa has mentioned, the HUMS in a super puma (any variant ... Unless someone can tell me it's different in a 225) already learns its caution threshold based on data collected over a period of time. When a major component is replaced, most HUMS indicators of that component are put into learning, during this period only the max/red threshold is set (which is a set max from manufacture for that indicator/gear). After a set number of data points are collected the HUMS will set the caution/yellow threshold based on the average of the points collected (ie. mean plus .1 g). The yellow caution will vary for each aircraft while the red threshold is a set number and applies to all.

As far as cockpit awareness, I think Mitchaa has summed it up there as well.

dervish

2nd May 2016, 15:53

they have no reason to ground the fleet as they don't have any evidence to support that grounding

Surely grounding is the safety default and they need evidence to continue flying? Requiring evidence to support grounding is the commercial default.

CTYONE

2nd May 2016, 15:58

A petition to remove the EC225 Super Puma helicopter from service, started by an oil worker following the crash, has now been signed by more than 14,800 people - some of them relatives killed in other incidents.

https://www.change.org/p/civil-aviation-authority-remove-the-airbus-225-super-puma-from-service?recruiter=305505445&utm_source=share_petition&utm_medium=copylink

LastMinute

2nd May 2016, 15:59

AIBN announcement (http://www.aibn.no/About-us/Nyhetsarkiv/The-Helicopter-Accident-Invitation-to-Press-Conference-at-Haakonsvern-naval-base-in-Bergen-Tuesday-3-May-at-1400-hours) of press conference tomorrow (Tuesday 2016‑05‑03) at 14:00 CEST.
Includes photos of recovered wreckage.

heliguy77

2nd May 2016, 16:02

ALTERNATIVES?

AW189 - ...the two of bristow was park and he don't use it (a sheat)

This is not true (see attached pic)...

ALTERNATIVES?

S-61 - ...a T-REX with a rotor

:confused:

ALTERNATIVES?

AW101 - ...A bad copy of NH-90 but why not why not 'depend of the price (a 225 is 23Meuros)

"A bad copy of NH-90"?!?! Have you ever seen a AW101???

dipperm0

2nd May 2016, 16:06

On the Aviation Investigation Board Norway are pictures of the wreck.

The Helicopter Accident: Invitation to Press Conference at Haakonsvern naval base in Bergen Tuesday 3 May at 1400 hours

Think we shall not get answer before that time.

mk.69

2nd May 2016, 16:18

Looking close to the Picture IMG_0093 of the AIBN Announcement link from post #315: According to the damage of the tailrotor blades it seems to me that the tailrotor was still spinning on impact. Wouldn't the TR stop rotating when the MGB seizures?

mk.69

2nd May 2016, 16:22

Looking close to the picture IMG_0093 of the AIBN Announcement link from post 315:

According to the Tailrotor blade damage it seems to me that the TR was still spinning on impact. Wouldn't the TR stop rotating when the MGB seizures?

OnePerRev

2nd May 2016, 16:38

The two photos on the AIBN site don't seem to include further closeup of main rotor gearbox or the rotor. The first photo on the other hand may be showing us one of the lifting struts still attached to airframe, unless that is something else. Tail blades smashed, evidence of full speed rotation when they hit something. I would guess secondary, but shortly after the main rotor, possibly even a main blade or two as the main head peeled off.

Pablo332

2nd May 2016, 16:42

Pablo, are you referring to the upper bearing where the mast comes through the top of the housing? Unfamiliar with this aircraft, but I think I understand that there are oil jets that keep lube coming to that bearing. If the lube doesn't get there, how does a rising temperature get detected? (I think I see your point on an impending bearing failure being picked up by a HUMS sensor).
On the 225 the MRH shaft is supported in the lift housing by 2 taper roller bearings. The bearings are lubricated by internal drillings in the lift housing and MGB Flared housing.

All should become a lot clearer tomorrow.

OnePerRev

2nd May 2016, 16:42

.. Just hit the refresh button on the AIBM site thinking they would add more, and now it only has one photo, the second one. Did they remove a photo?

dipperm0

2nd May 2016, 16:51

Sad duty

The fuselage has been totaly destroyed. How investigators are they going to make the diffecence between what caused the accident and what has been torn away by the impact on ground or sea surface?

You are right, they removed 2 pictures

dipperm0

2nd May 2016, 17:23

In the left background of picture post 323 you can see the MGB, it looks like it is upside donw with the input shaft of engine n° 2 visible

spectral

2nd May 2016, 17:26

175 is 16 pax

Yes it's true but if you want to keep the full range you put only 16 little Chinese inside...but sorry for this "the fat oil worker" you can put only 12 to keep the full range of the aircraft...352 (12 pax) km

Quote:
Originally Posted by spectral View Post
AW189 - ...the two of bristow was park and he don't use it (a sheat)
Works for everyone except Bristow! Hmmm?

Sorry but is true Bristow don't like this aircraft i don't know why but is fact...

For the SIN of Airbus if he write this type of SIN 48H after the grounded is certainly because the design of 225 is safe and the cause of accident is certainly not an aircraft problem...I don't imagine to write this type of document with a part of doubt...

But i think is too late now the 225 share the same history of the main frame "Super Puma" if you really look the crash of 225 it's only three 2 ditching (no injurie) and 1 crash of OJF...all the other incident it's L2 or L1 in total of 8...and nothing impacted Airbus ou Eurocopter or Aérospatiale only maintenance defect....You can impact Eurocopter only for the design of mgb shaft with result of 2 ditching and no injurie....

But a the END of the story, for OJF the price is very high, 13 life and depend of the following of story "maybe 5000" People lost their job in factory. Certainly all the oil & gas cancel their next order of 225 and certainly ask a compensation for their aircraft grounded or because nobody want to flight again with this aircraft just CHC is 40 225. You can imagine the following.

And it's was certainly interesting to calculate how many flight hour has the super puma family in a world to have the ratio flight hour/incident and compare with other aircraft (when you remove the maintenance defect).

dipperm0

2nd May 2016, 17:31

closer from the middle, the grey component in the backward, with the rounded silhouette of the accessory module perfectly visible

dipperm0

2nd May 2016, 17:35

Picture of the MGB with what seems to be the RH servo control still attached

FNTC

2nd May 2016, 17:44

Shell Norway has supended all flights with CHC Norway, including S92s today.
Shell stanser alle CHC-flyvninger i Norge - NRK Norge - Oversikt over nyheter fra ulike deler av landet (http://www.nrk.no/norge/shell-stanser-alle-chc-flyvninger-i-norge-1.12928395)

Translation of statement:
"- In light of Friday's tragic accident, Shell is reviewing CHC Helikopter Service in Norway as an added assurance that all operational requirements and defined standards are met, said Kitty Eide, communications manager for Shell, operations and projects in Norway."

and:

"- We have four regular flights to Draugen per week and we are currently working to find alternative helicopter suppliers for our operations in Norway in this temporary situation."

spectral

2nd May 2016, 18:35

REDL is a L2 a different design of MGB it's same if you compare a rabbit and a hare it's look like similar but different....

And REDL have so many alert (ignored) before the crash , this is the result of lot of chips and corrosion!!!!!

twinstar_ca

2nd May 2016, 19:04

i hate seeing all that damage!!!! :eek::sad:

helicrazi

2nd May 2016, 19:38

Bristow Grounds Airbus EC225 Helicopters After CHC Crash - WSJ (http://www.wsj.com/articles/bristow-grounds-airbus-ec225-helicopters-after-norway-crash-1462201212)

Reads like they have ruled out gearbox failure to me which is quite concerning because if it wasn't the gearbox responsible for ripping the head off the aircraft, what was it? :ooh:

Oh well, enough speculation, I guess we will find out at the press conference tomorrow where their area of interest is.

Any chance of posting the full article?

alby3z

2nd May 2016, 19:56

Any chance of posting the full article?

I have copied and pasted the whole article from wsj site:

The fallout from Friday’s deadly crash of an Airbus Group SE helicopter widened Monday as investigators begin analyzing black box data that could explain the cause of the accident.

Bristow Group Inc. on Monday said it would ground some EC225 helicopters in Australia, after regulators in Norway and the U.K. barred passenger flights with the model.

The company said it was suspending flights of six of its EC225 helicopters in Australia, but that three others used for search-and-rescue operations would continue to be used. In Norway and the U.K., where Bristow has a number of the helicopter’s registered, the model has also been grounded for emergency operations.

On Friday, an EC225 flown by CHC Helicopter Services crashed while flying to Norway’s Bergen Airport from Statoil AS A’s Gullfaks B oil field, killing all 13 people onboard. The cause of the accident is still unknown.

Norway’s air accident investigators said Monday that data from the combined flight data and cockpit voice recorder had been extracted. “The data is of good quality and is sent back to Norway for analysis,” the Accident Investigation Board Norway said. The U.K. Air Accident Investigations Branch extracted the information.

The rotor appears to have separated from the helicopter, a highly unusual occurrence.

helili

2nd May 2016, 20:07

Try this one

Bristow Grounds Airbus EC225 Helicopters After CHC Crash - WSJ (http://www.wsj.com/articles/bristow-grounds-airbus-ec225-helicopters-after-norway-crash-1462201212)

Pablo332

2nd May 2016, 20:09

Bristow Grounds Airbus EC225 Helicopters After CHC Crash - WSJ (http://www.wsj.com/articles/bristow-grounds-airbus-ec225-helicopters-after-norway-crash-1462201212)

Reads like they have ruled out gearbox failure to me which is quite concerning because if it wasn't the gearbox responsible for ripping the head off the aircraft, what was it? :ooh: (MRH retention nut installed incorrectly?)

Oh well, enough speculation, I guess we will find out at the press conference tomorrow where their area of interest lies.
There is no main rotor head retaining nut on the 225. If the main rotor shaft retaining nut had failed we would not have the lift housing and suspension bar with the shaft assy.

Non-Driver

2nd May 2016, 20:16

There's an 8-K been put out by BRS today:

Bristow Group Inc. - SEC Filing (http://ir.bristowgroup.com/mobile.view?c=91226&v=202&d=3&id=aHR0cDovL2FwaS50ZW5rd2l6YXJkLmNvbS9maWxpbmcueG1sP2lwYWdlP TEwOTA1NDgzJkRTRVE9MCZTRVE9MCZTUURFU0M9U0VDVElPTl9FTlRJUkUmc 3Vic2lkPTU3)

Essentially just says how many aircraft affected in which regions. All grounded bar life-saving SAR.

Pablo332

2nd May 2016, 20:32

Thanks for the clarification Pablo, wasn't sure myself but as you say in the event of 'Jesus nut' failure on other aircraft types that have the nut installed, you lose the head from the mast rather than the mast from the MGB.

Helicrazi, Another link...

Bristow Grounds Airbus EC225 Helicopters After Norway Crash - NASDAQ.com (http://nasdaq.com/article/bristow-grounds-airbus-ec225-helicopters-after-norway-crash-20160502-00785)
The buckling of the MRB LE protection at approx. 1/3 of the span of the MRBs still concerns me, it’s not evident on the L2 incident. Did the massive overpitch occur as a result of the failure or the cause of it?

The Main rotor flight controls run under the No2 Engine (grandfather design rights). Power turbine disk intrusion has been addressed allegedly by contained blade shedding. Gas generator turbine disk failure has not been looked at.

helicrazi

2nd May 2016, 20:33

Thanks all :ok:

Lonewolf_50

2nd May 2016, 20:49

The Main rotor flight controls run under the No2 Engine (grandfather design rights). Power turbine disk intrusion has been addressed allegedly by contained blade shedding. Gas generator turbine disk failure has not been looked at. Thanks for already addressing my next question, your kind reply on the oil/bearings is much appreciated. :ok:

electrotor

2nd May 2016, 20:56

1. Suspension bar lower end (rotated through about 150 degrees to point up) which attaches to the forward or aft lifting frame. This would indicate that part, if not all of the ring above the conical housing detached with the rotor head.
2. Broken pitch rod - upper end rotated through about 180 degrees.
3. Scissor link clevis but scissor link detached
4,5,6 Blade dampers outboard ends detached. The detached plate for the outboard end of the damper at 5 has rotated to face out. Normally, when still attached to the rest of the damper assembly it would face inboard. Damper assemblies at 5 & 6 have rotated to point up whereas assembly at 4 has rotated to point down.

VortexRinger

2nd May 2016, 21:09

electrotor..how did you determine that the suspension bar in the picture is the forward one?

electrotor

2nd May 2016, 23:53

Apologies VortexRinger, I meant only to state that it was the lower end of the suspension bar. I was looking at a picture of a complete MRH head at the time which had the blue blade in the forward position and directly above the forward suspension bar. Earlier post now corrected.

Satcomm

3rd May 2016, 00:29

I don't believe they have ruled out gearbox failure. They have just ruled out the vertical shaft issue that caused the previous 225 ditchings.

"Airbus Helicopters said initial evidence suggested no link with two previous incidents in Scotland involving Super Puma H225 helicopters."

Still seems to closely similar to G-REDL to believe at the moment that it could be anything other then the gearbox locking up. Which I guess as in G-REDLs case, was an isolated incident to that variant (AS332L2). Airbus may already be considering this an isolated one off incident in the H225. It is a different aircraft and the only time (if it is the case) it has happened.

That said, the fact that Bristow has suspended 225 flights would make one believe that it is NOT maintenance related on CHCs behalf. Why would they park millions of dollars worth of aircraft if they knew it was a maintenance issue by the other operator .... Same token, I guess in today's downturn, being able to park aircraft at customers expense while putting other assets to work may not sound to bad.

As far as the 225 goes, would be hard to think it's going away. There isn't enough aircraft out there to fill the role and as a few have already said, there isn't an aircraft that can do it for the price ... Full pax, full fuel. At the end of the day Big Oil comes down to profits ... They will have their "advisors" inform them what they want to hear and the 225 will be back in service. Wasn't to many years ago everyone was calling for the S92s head, petitions signed, pax refusing to board, etc.

coolyhat

3rd May 2016, 02:54

Pablo332

3rd May 2016, 05:06

electrotor..how did you determine that the suspension bar in the picture is the forward one?
It’s the LH suspension bar, as it’s the only bar that has it’s pin inserted CW when viewed from above.

megan

3rd May 2016, 05:14

Don't know if this has been posted prior, CAA Norway has revealed the main gearbox of the accident helicopter was replaced on January 17. CHC then had the rotor head replaced on March 27.

Evil Twin

3rd May 2016, 05:33

our recommendation is NOT to fly this POS until cause is determined and rectified.

Not exactly unbaised if you ask me ;-)

Special 25

3rd May 2016, 05:44

".......the fact that Bristow has suspended 225 flights would make one believe that it is NOT maintenance related on CHCs behalf. Why would they park millions of dollars worth of aircraft if they knew it was a maintenance issue by the other operator "

Presumably, because the National authorities (CAA and NCAA) have grounded the EC225 for all but emergency flights. Didn't give Bristow a lot of choice. I don't see how this decision points to any conclusion at this early stage.

Saw a reference to a Press Conference today. When is that?

Smokeyboy

3rd May 2016, 05:56

Saw a reference to a Press Conference today. When is that?

| aibn (http://www.aibn.no/About-us/Nyhetsarkiv/The-Helicopter-Accident-Invitation-to-Press-Conference-at-Haakonsvern-naval-base-in-Bergen-Tuesday-3-May-at-1400-hours)

squib66

3rd May 2016, 06:44

Shell have suspended all flying in Norway with CHC (at least temporarily). Some grumbling among Shell workers in the UK, who have been told to turn up to CHC as normal (this is the third CHC accident in Europe since Shell moved to them).

reefrat

3rd May 2016, 07:19

electrotor

3rd May 2016, 07:48

Well spotted Pablo332.
I already corrected my posting before you pointed this out.

Pablo332

3rd May 2016, 08:18

1.I know nothing about aerodynamics.
2.As a merchant mariner I have a tenous grasp of hydodynamics.
3.I presume that the main rotor continues to rotate in the normal direction, clockwise in this case, when it detached.
4. This is the case with a ships propellor when a drive shaft fails.
5. Question is why is the majority of damage to the blades on the trailing edges.
The trailing edge has a carbon skin top and bottom separated by a nomex honeycomb/foam core and is relatively weak.

The LE spar is constructed of glass fibre roving strips impregnated with resin and is relatively strong.

Best nautical analogy from a strength point of view would be to think of the LE as the mast and the trailing edge as the sail.

epkp

3rd May 2016, 08:33

It is very sad what happened, nevertheless, I am an EC225 driver for years and AS332 for décades, I truly rely on this Aircraft. So wait and see what is going to be published this afternoon.
By the way Johni, are you not on the Sikorsky payroll?;)

roundwego

3rd May 2016, 09:41

johni, what two EC225 crashes are you talking about?

HeliComparator

3rd May 2016, 09:41

Nope, I think EC make some great aircraft, but I think this is the death-knell for the 225. They only just managed to restore confidence after the last two crashes.

I think the S92, EC175, AW189, AW169 etc would easily be able to fill the gap. Sure, the 225 has good lift/fuel capacity, but at what cost?
The S92 and EC225 had some design weaknesses that caused ditchings, and in the case of the 92, fatalities. Ditto 139. Historically new types have always had design weaknesses. It seems incredibly naive to presume that the 175, 189, 169 do not. It is just a matter of time before they manifest the problems.

donut king

3rd May 2016, 09:58

The S92 and EC225 had some design weaknesses that caused ditchings, and in the case of the 92, fatalities. Ditto 139. Historically new types have always had design weaknesses. It seems incredibly naive to presume that the 175, 189, 169 do not. It is just a matter of time before they manifest the problems.

"Ditto 139" ?????

Outwest

3rd May 2016, 10:15

"Ditto 139" ?????

Brazil....

HeliComparator

3rd May 2016, 10:16

"Ditto 139" ?????
By which I mean design weaknesses. I'm not that familiar with the 139's accident history but if it's tail boom design issues didn't cause an accident I suggest that was lucky. And tail rotor - but as I said not that familiar with it.

donut king

3rd May 2016, 10:36

By which I mean design weaknesses. I'm not that familiar with the 139's accident history but if it's tail boom design issues didn't cause an accident I suggest that was lucky. And tail rotor - but as I said not that familiar with it.

IIRC, 139 t/r blades issue. Back to this tragedy, it just 'appears' that several failures focused on MGB/ MGB area. Recall that a witness stated seeing a fire on top of the Norway 225 prior to ground contact.

And now the petition is over 20000 signatures. Have to respect the passengers (families) concerns.

Condolences to crew and pax families:(

gulliBell

3rd May 2016, 10:44

@HeliComparator post # 368. An AW139 threw a TR blade in Hong Kong causing the whole TGB assembly to depart the scene resulting in a ditching and loss of the aircraft (no fatalities however).

Profitable event for the company concerned, they received both a hull loss insurance payout and compensation from AW.

FC80

3rd May 2016, 11:18

Is the AIBN press conference going to be streamed online anywhere?

HeliComparator

3rd May 2016, 11:28

IIRC, 139 t/r blades issue. Back to this tragedy, it just 'appears' that several failures focused on MGB/ MGB area. Recall that a witness stated seeing a fire on top of the Norway 225 prior to ground contact.

And now the petition is over 20000 signatures. Have to respect the passengers (families) concerns.

Condolences to crew and pax families:(
Yes of course it is a sensitive area, and one can understand the relatives feelings, and those of other passengers, however I dislike seeing mob rule and hysteria borne out of ignorance and the stupid idea that a brand new helicopter is somehow safer than one with a few 100,000 hrs under its belt, determine a less safe course of action. If you look at the petition signatures I would suspect that most people signing have never even seen an EC225 in the flesh. It is the sort of thing that does the rounds on Farcebook and lots of folk looking for something to be righteously indignant about, but with zero knowledge, sign up to.

dipperm0

3rd May 2016, 11:42

@helicomparator

+1

jc23

3rd May 2016, 12:02

I fully agree with epkp feeling.
Wait and see what is going to be published this afternoon.

AAKEE

3rd May 2016, 12:08

Havarikommisjonen om helikopterulykken - Video (http://www.nrk.no/video/PS*f2781)

Helicopterfixerman

3rd May 2016, 12:11

That's a fair point Mitchaa, but the petition calls for the EC225 (sic.) to be removed not the AS332L/L1/L2. Just the 225. From memory, before this accident (which I am certain now that you will find is not linked to the L2 break-up - watch this space - Think fwd suspension bar airframe attachment) there have been a ditching due to the oil pump drive shaft fracture and one ditching due to pilot error (ETAP?).

Apart from (most of) the airframe, to all intents and purposes the 225 is a completely different aircraft to the L, L1 and L2.

Unfortunately the public see the airframe and think they are all the same. They are not. Just like a B733 bears little or no relation to a B738.

Outwest

3rd May 2016, 12:27

Any Norwegians care to translate the press conference highlights for us?

Satcomm

3rd May 2016, 12:28

Mitchaa I agree that seems high when you break it down like that, but haven't 2 of those incidents been deemed pilot error? Can't really include pilot error into the Puma issues. As for the other 4, 3 have been 225, making that number more like every 28 months for an incident. As for a fatality in the 225, first time .... Has made me consider the 225 as one of the safest to date. The 225 was the only, of popular choice, S92/AW139/S61/S76/AS332, that had not had a fatal accident.

domperry

3rd May 2016, 12:30

Shonky translation via google of the caption on screen says "technical failure not human (pilot?) error".

Satcomm

3rd May 2016, 12:30

Sorry helicopterfixerman, didn't mean to copy you, your post must have been posted as I was typing

HeliComparator

3rd May 2016, 12:31

You make a very valid point HC:ok:

However, fact of the matter is, there has been 6 accidents/incidents with Airbus helicopters in the North Sea in 7yrs.

We can quote hundreds of thousands of hours spanning decades but one accident/incident on average every 14 months is a scary scary statistic for the public to accept.

3 cases were manufacturer defects, 2 were human error, the 6th, well hopefully we find out more this afternoon.
So in terms of the 2 pilot error ones, I suggest they should be discounted in terms of blaming the airframe. The two ditchings due to bevel gear shaft - possibly avoidable with more rigorous use of HUMS abut anyway problem identified and sorted. REDL with its planet gear, there is perhaps some debate as to whether it was avoidable with more rigorous maintenance procedures (trivial things like communications with the manufacturer in writing, not over the phone). This is the only one that leaves me a bit uncomfortable. But then again if you look at the number of hours flown by the SP fleet etc...

And now something which is looking like a maintenance error (although we don't know for sure yet).

All that set against the fact that the SP family was by far the predominant type flying the N Sea and so not surprisingly had the most accidents.

I am certainly not trying to suggest that the recent accident rate is acceptable nor that we shouldn't be striving hard to dramatically improve it. What I am saying is that to dump a well tried and tested aircraft which has had its issues dealt with, for new stuff with as yet completely unknown issues, is madness. One thing is for sure, there WILL be an accident with a 189/169/175, and probably more accidents than if the 225 remained in service doing the bulk of the work.

charlieDontSurf

3rd May 2016, 12:33

Summary of the pressbrief:
-Technical malfunction, not pilot error.
-Everything seemed normal until the accident occured, and it happened VERY quick.
-No new info other than they need to do more research, review the documentation, HUMS etc.
-They let the press view the parts of the wreckage.
-They haven't specified if it's a part that failed or maintenance error.

Outwest

3rd May 2016, 12:34

Thanks Charlie....

How Nice

3rd May 2016, 12:37

Google translation:

2:21 p.m. crashed due to technical fault ein AIBN vindicated ein press briefing en that helikopterstyrten was a technical car accident, and not a humanitarian failure.

FC80

3rd May 2016, 12:40

HC - what evidence is there that this was a maintenance error?

Nadar

3rd May 2016, 12:52

I'd like to add a little info from the press conferance:

- They had not been able to retrieve HUMS data from the accident flight, and they didn't think they would be able to.
- They wouldn't answer anything technical but made it clear that they shared what they found with "those with responsibility" like operator, manufacturerer and authorities. I interpret it as quite evident that they know much more that they were willing to share - so one could speculate what the reason for that could be.

charlieDontSurf

3rd May 2016, 12:57

I think the accident rate we have seen the past years is unacceptable.
There are different types-and reasons for the accidents, but the rate is unacceptable anyway. It's starting to look like the trend that has been with in-land aerialwork in Norway for some time. But offshore-ops is a different league when it comes to regulation, redundancy, crew and crew training. There shoundn't be that many accidents. Period.

I totally understand that people are loosing faith in the 332/225 now.
Yes, the 92 has had it's accidents too, and incidents.
But WHY does this happen again and again?
And WHY would it be expected that new types will have similar accidents? I don't think that's acceptable.

An accident is very expencive. And the cost lasts for selveral years.
That's why companies and manufacturers should be more proactive to prevent accidents instead of improving AFTER the accident. Some companies do a very good job.
If you "save" money on safety, it will eventually backfire.

I'm not blaming CHC or Airbus of anything, but watch the aftermath after this accident, and see what the consequenses will be the next months.

terminus mos

3rd May 2016, 13:18

So in terms of the 2 pilot error ones, I suggest they should be discounted in terms of blaming the airframe. The two ditchings due to bevel gear shaft - possibly avoidable with more rigorous use of HUMS abut anyway problem identified and sorted. REDL with its planet gear, there is perhaps some debate as to whether it was avoidable with more rigorous maintenance procedures (trivial things like communications with the manufacturer in writing, not over the phone). This is the only one that leaves me a bit uncomfortable. But then again if you look at the number of hours flown by the SP fleet etc...

And now something which is looking like a maintenance error (although we don't know for sure yet).

All that set against the fact that the SP family was by far the predominant type flying the N Sea and so not surprisingly had the most accidents.

Phew, for a minute I was worried HC but now that's all cleared up, thanks.

Now that Airbus has lifted the suspension, my regulator is mute, having not suspended flights, all I have to do is persuade our operator to lift their (apparently unnecessary) suspension and the pilots to fly as normal and all will be statistically fine. :(

AmeliaJane

3rd May 2016, 13:20

I took down notes for my non-Norwegian speaking colleagues:

Dealing with a technical accident, not caused by flight crew (clarified to: they don’t see any signs of a typical precipitating event that would indicate human error). Very sudden event.

Next steps are to review:

Wreckage
HUMS data
Maintenance documentation
Other documentation
Showed press the wreckage to demonstrate the enormity of the task and stated that it would take them a long time to figure out what happened.

Preliminary investigation reports would be issued when there’s something to tell. The CAA and others (Airbus and UK AAIB) are involved and thus aware of all information as it appears.

Follow-up questions by press gives a little more detail:

Cockpit voice recorder and other data indicates there was no human error on the part of the flight crew.

Sending some parts to the AIBN home base tomorrow to give them better access to their analytical equipment.

dipperm0

3rd May 2016, 13:21

Sorry for my poor english but I will try to answer CharlieDontSurf

Had the S92 been the main helo in NS, pilot error would have occured on S 92 - Should I blame the S 92 for that ? No, for sure,

Apate

3rd May 2016, 13:21

TM, I assume there should be a smiley in there somewhere?

Later edit: Thanks for the "grumpy" :ok:

Apate

3rd May 2016, 13:29

dipper, the term "pilot error" should be banished to Room 101 (refer to Google), please stop using it.

Like all accidents and incidents, it is important to understand why the error was made, not just stop at "the pilot got it wrong".

The S92 Cougar accident could have been blamed on the pilots, as they didn't ditch the aircraft when the SOPs clearly stated that was required.

Most of the time a large amount of the root cause lies with OEMs, whether it be bad design, bad manuals, no FCOMs, or might even be more basic than that in that the regulation is weak.

So should the aircraft (OEM) sometimes be blamed for "pilot error" - yes!!

jimf671

3rd May 2016, 13:33

... ...
I am certainly not trying to suggest that the recent accident rate is acceptable nor that we shouldn't be striving hard to dramatically improve it. What I am saying is that to dump a well tried and tested aircraft which has had its issues dealt with, for new stuff with as yet completely unknown issues, is madness. One thing is for sure, there WILL be an accident with a 189/169/175, and probably more accidents than if the 225 remained in service doing the bulk of the work.

Somebody earlier mentioned the problem that strengthening a component might mean moving the problem elsewhere and I think there is an analogy here with change of type. UK parliamentarians pointed out in their 2014 report that the Super Puma family were 60% of the NS fleet so it was unsurprising that they were involved in most of the accidents. A very popular helicopter type in service for 12 years and hundreds of thousands of flying hours before any fatality seems like not a bad record especially when compared to previous generations of aircraft. I'd rather it were better but it's not bad.

Our friend Helicomparator has not mentioned the S-92 but we should think about the enormous pressure that will inevitably now be on the S-92 fleet and supply chain.

whoknows idont

3rd May 2016, 13:40

TM, I assume there should be a smiley in there somewhere?

Full and proper sarcasm doesn't need any smileys.

charlieDontSurf

3rd May 2016, 13:44

Dipper:

-It was NOT pilot error.
-I just said that I understand that people loose faith in the 332/225, AS they would loose faith in any type that has a high accident rate.
-My point was the accident-rate, not wich type that crashes.
-I am not claiming that the S-92 or any other type is better, I just think there's been too many accidents lately. And Airbus have been involved in the latest, that we can agree upon?

MattBee217

3rd May 2016, 13:49

Somebody earlier mentioned the problem that strengthening a component might mean moving the problem elsewhere and I think there is an analogy here with change of type.

Working for one of the major manufacturers I can attest to this. We've run into issues with cracking and you're forever chasing it down - adding straps, doublers, redesigning, etc. There's a frequency that sets up and you can fix it in one spot but it moves.

letmein

3rd May 2016, 14:01

jimf671

3rd May 2016, 14:05

The House of Commons Transport Committee, Offshore helicopter safety,
Second Report of Session 2014–15 (http://www.publications.parliament.uk/pa/cm201415/cmselect/cmtran/289/289.pdf), at Table 1 on page 11, shows the pattern of accidents in the UK sector from 1976 to 2013.

Can we agree that overall there is a dropping trend in both accidents and accidents per 100000 hours?

Worryingly, the pattern of a fatal accident every three years seems to stubbornly remain.

byeskille

3rd May 2016, 14:09

Here are some photos of the parts shown at the press conference - click on them for full resolution (photo: Tor Erik H. Mathiesen / NTB Scanpix):

https://gfx.nrk.no/b4fR-2OSeHSRNj4dpQQc7AqzdBCQL6r62l6RBBqGAz1g (https://gfx.nrk.no/b4fR-2OSeHSRNj4dpQQc7AmBgp3i0J_F_msMZXgtt_kw)

https://gfx.nrk.no/lJMJUMUSy4WsX9mnf9vATAi79xCpKhe6X9kdsHKgtU7w (https://gfx.nrk.no/lJMJUMUSy4WsX9mnf9vATALGe8bm8sN88hBndSDCwZ-g)

https://gfx.nrk.no/x8j9gKAVq29tCcO4SDL2tQjHTnxrTkDy8sq91B8vl3sg (https://gfx.nrk.no/x8j9gKAVq29tCcO4SDL2tQ9KlSjIKBmFJrEhpbZDOeLg)

https://gfx.nrk.no/9p3yruZtVe7BpEV7dPUlCwHd6Ka4b6sefn5r9vnBGfrw (https://gfx.nrk.no/9p3yruZtVe7BpEV7dPUlCwFxGbMo2wq6JjB5H84vGorA)

aheoe26104

3rd May 2016, 14:18

Ok so, my take..

-It happened in the blink of an eye, no time for Mayday, etc.
-Given mode of failure, rotor head twisting off, epicyclic gear breakdown is likely.
-The HUMs probably did not indicate pending failure before flight. (..but HUMs data could have been misinterpreted)
-More details will trickle in over the next few months, years, before final analysis.
-Accident happened within one of the most professionally run organization in helicopter industry.

= H225 grounded for a long time (maybe forever)//confidence shattered
...and here I was hoping to be back on line tomorrow....

AH's confidence in saying they don't want to ground the 225 and the announcement had me on the edge of my seat about the reason for their confidence and the very short time span they arrived at their stand point. But years in the industry told me this one will not go away in a week.. Still, the same years of experience in the industry left me perplexed with AH's response to date.

robsch

3rd May 2016, 14:27

Is this the gearbox?

HeliComparator

3rd May 2016, 14:30

Phew, for a minute I was worried HC but now that's all cleared up, thanks.

Now that Airbus has lifted the suspension, my regulator is mute, having not suspended flights, all I have to do is persuade our operator to lift their (apparently unnecessary) suspension and the pilots to fly as normal and all will be statistically fine. :(
For clarity I am not suggesting the 225 restarts O&G flights right now. I would certainly want to have a fairly good idea of the cause of this latest accident first, and then make an intelligent decision. What I would want to avoid is "out of the frying pan into the fire" by making unintelligent decisions based solely on emotion and miraculously expecting a new generation of helicopters to never have design problems.

aheoe26104

3rd May 2016, 14:31

.....
.... if its a maintenance error, tell us and ........
also tell us what they will do to prevent it happening again (ever) in future.

HeliComparator

3rd May 2016, 14:33

also tell us what they will do to prevent it happening again (ever) in future.
If only it were possible to prevent any future maintenance errors. And then, I guess, "do something" to prevent any future pilot errors. Hmmmm, now that would be a wonderful fairytale land! Ain't going to happen though.

aheoe26104

3rd May 2016, 14:38

If only it were possible to prevent any future maintenance errors. And then, I guess, "do something" to prevent any future pilot errors. Hmmmm, now that would be a wonderful fairytale land! Ain't going to happen though.
Agreed. I remember how a previous client was insisting our company produce a set of actions that would prevent an oil filler panel on the 76 of not being closed properly from (ever) taking place again. And in this case they will be pushing even more for rectification and assurances..

Rabina

3rd May 2016, 14:38

Logically I'd agree Mitchaa. Except no one is about to point fingers at potential mistake makers because of the fallout. If it looks like a maintenance error, you need to pull work sheets, components used, trace back down the supply chain from stores back to the OEM etc. That's what's going to take time.

Our company works with the Norwegians and have never found them lacking in any respect. I have the highest regard of them and their people, which is not an excuse or disclaimer for what happened Friday, just a fact.

Spanish Waltzer

3rd May 2016, 14:40

26500lbs

3rd May 2016, 14:44

One says technical fault and one says technical error.

Same word in norwegian. They used word “feil”. Can mean fault or error.

aheoe26104

3rd May 2016, 14:44

Anyone know if ERA and Sonair continue flying? And who else is operating the 225 aside from CHC/Bristow/Babcock MCS...
SonAir also not flying.

Spanish Waltzer

3rd May 2016, 14:48

Every day is a school day! Thanks 26.5

Satcomm

3rd May 2016, 14:48

Mitchaa, if price of oil was right, it would be airborne. It was only the last fatal accident off Scotland that CHC was quoted saying "Customers are asking us to return the aircraft to service." This after CHC had voluntarily suspended flights. Also to support this, CAA's own report back around that time titled/taking about " Offshore helicopter safety report reveals 'macho bullying culture". Sorry, and I hope I am 100% incorrect, but it is hard to believe those "advisors" really have a unbiased opinion.

OnePerRev

3rd May 2016, 15:02

Rumor is that it was the forward strut, lower pin "came loose" and no longer carried load, Remaining two not sufficient to carry loads, everything else ripped apart.

Q: same struts for 225 as previous versions?

As we earlier noted, this model is considered new, but the certification basis is clearly associated with previous models. Fatigue evaluation of structure is from amendment 20, 1980, which is not the same as today. New versions require threat assessment, which may have better predicted (and thus mitigated) issues with the struts and their attachment.
Even to the old standards, questions should be asked to ensure that the new aircraft and new loads are used to show that same or similar parts are safe.

domperry

3rd May 2016, 15:12

The latest from Airbus:
"Airbus Helicopters welcomes the announcement made by the AIBN today.
The investigation will now solely be focused on potential root causes of a technical failure, such as design, production, and/or maintenance.
Airbus Helicopters continues to provide its full support to the AIBN investigation."

Helicopterfixerman

3rd May 2016, 15:22

There has been at least one instance of the incorrectly sized pin being inserted in the forward suspension bar attachment. The two aft sets of pins are a smaller diameter than the front ones. In this case, the error was discovered on the ground when collective was raised/power applied and the crew experienced a "clunk" as the bar lifted in it's bracket, the MGB effectively nodding up and down as power was applied and removed..

I'm not saying this has happened here. It may be possible that the correct pin has been inserted and has failed (not sure how likely that is to happen) or the correct pin has been inserted and the two nappy pins have not been fitted to preclude it slipping out. Yes it is subject to inspection after the installation, but if the incorrect pin can be fitted and no-one notices............

To inspect this pin, a panel on the firewall needs to be removed. Awkward to get to as you need to reach in under the RH engine, in a contortionist fashion to remove the panel fasteners.

I'm not saying any of this is likely or probable, but it is certainly possible. If the failure is a maintenance one.

HeliComparator

3rd May 2016, 15:30

If it does turn out to be a maintenance error, let's hope the investigation doesn't just say "engineer error - they sacked him so no more problem" but rather looks at all the factors that might have contributed such as a company on the verge of bankruptcy, redundancies looming, lots of pressure from the top on costs, customers demanding cost reductions etc plus of course the usual possible personal issues.

AmeliaJane

3rd May 2016, 15:32

I have now seen two quotes reported from the AIBN press conference. One says technical fault and one says technical error. It may be a translation thing but these two words, fault and error have pertinent different meanings in my mind. Can anyone clarify?

They said "teknisk ulykke" or "ulykke av teknisk art" (i.e. technical accident) can't remember exactly. I made particular note of the term "ulykke". They didn't use the term "teknisk feil" (technical error/fault). A lot of the reporting does too much interpreting in my opinion, as in the "no human error" element, which was only about the flight crew (this was quite specific without stating that it didn't mean human error hadn't taken place elsewhere).

26500lbs

3rd May 2016, 15:42

They said "teknisk ulykke" or "ulykke av teknisk art" (i.e. technical accident) can't remember exactly. I made particular note of the term "ulykke". They didn't use the term "teknisk feil" (technical error/fault). A lot of the reporting does too much interpreting in my opinion, as in the "no human error" element, which was only about the flight crew (this was quite specific without stating that it didn't mean human error hadn't taken place elsewhere).

You are quite right AmeilaJane. The reporting afterwards becomes clouded and depending on which paper you read, different things are quoted. At least one paper is quoting “teknisk feil” and “teknisk svikt”. I cant remember now exactly which wording was used at the press conference. Slight semantics, but a teknisk svikt is quite a harsh usage I think at this stage.

TylerMonkey

3rd May 2016, 15:55

roundwego

3rd May 2016, 16:00

I am very disappointed in the way the Norwegian AAIB have conducted their recent "press conference". It would seem there is lots of room for misinterpretation of statements made by them. The BBC, for instance, is quoting the Norwegian AAIB spokesman as saying;-

"On the basis of the facts we have, this involves a technical fault; it isn't human error," the director of the board's aviation department said."

Can they already say it was not a maintenance error? I suspect he/she meant that it wasn't a piloting error.

And as to allowing the press into the hangar to view the wreckage and take photos, I find this extremely irresponsible.

I can't see the UK AAIB behaving like this.

whoknows idont

3rd May 2016, 16:14

So the forward suspension bar pin is a larger diameter. If a smaller pin from a rear strut is inserted no one notices this quickly and possibly nappy pins it in place. That to me puts some major blame on engineering design for not making the smaller pin a longer length or different head shape or at least some obvious difference so the poor AME doesn't grab it by mistake. What a perfect fit for Murphy's law.

One should figure it out once there is a bigger pin left over which doesn´t fit anywhere... Also every experienced mechanic will clearly notice if the fit is too loose. But according to Helicopterfixerman this did happen before so never say never.

helili

3rd May 2016, 16:14

If you insert a smaller pin fwd, you will notice hat you are missing one pin. Dont think that will hppen in a professional company.

SimCaptain

3rd May 2016, 16:32

roundwego

3rd May 2016, 16:47

roundwego,

In Norwegian language - the term "Teknisk feil" in this context equals to something technical going wrong with the helicopter. They did not say anything else. I.e. - They said it was not a pilot error. Nothing was said about maintenance error.

I read in the Norwegian newspaper VG (http://www.vg.no/nyheter/innenriks/helikopterstyrten-i-hordaland/havarikommisjonen-helikopterulykken-skyldtes-teknisk-svikt/a/23673753/) that there was only less than 1 second notice from fault detection until the rotor snapped.

I am only a pax on the Super Puma. I do short inspection jobs in the North Sea. I have recently gone through the repetition course for the HUET and even the EBS (emergency breathing system) wich is now mandatory on UK sector. I'm not comfortable with the Super Puma. If they would only have time to ditch it every time.... - I could at least get use of my training.......
Hi SimCaptain. You have proved my point that interpretation of the spoken work leaves room for misunderstanding or misinterpretation. I wasn't at the press conference but I have yet to see any written statement issued at the time of the conference to back up any verbal statements. It is my view that Norwegian AAIB should not have held a face to face press conference at this early stage. All they needed to do was issue a preliminary report which should have been issued in both Norwegian and English, the English version having been checked for correct and unambiguous translation.

I sympathise with your situation regarding having to travel offshore under the present circumstances irrespective of the type you fly in.

DTD585

3rd May 2016, 16:50

Has anyone else noted how little damage there appears to the aft transmission cowling?

This would suggest that the rotor exited up and forward.

HeliComparator

3rd May 2016, 16:56

Any fatal accident is horrible, most particularly for those left behind. But beneath all the hype we should perhaps try to maintain a sense of perspective. Every 3 days, 13 people die on the UK's roads. But nobody seems that bothered about it unless they are directly affected. But if 13 people die in an offshore helicopter once every 5-10 years, all hell breaks loose. Why are we so inconsistent in our attitudes?

Not saying we shouldn't strive to do much better, but flying offshore in a helicopter including an EC225 is still pretty safe by comparison to lots of other stuff we find acceptable. I survived a whole career of flying Super Puma types most working days as did nearly all my colleagues. I can understand the feelings of the passengers but I think it would help to make them feel better if they thought about the actual risk rather than the perceived one.

tarkay01

3rd May 2016, 17:03

squib66

3rd May 2016, 17:09

Is this not a single point of failure? If one leg of the tripod breaks, it seems that the rotor will come off.

That's why they are critical parts subject to extra inspection. The rotor/ mast are themselves a series of single point of failures on every helicopter.

byeskille

3rd May 2016, 17:13

In an interview with Norwegian Broadcasting (NRK), the head of the AIBN aviation departement Kåre Halvorsen now said this:
– We have recovered many parts of the gear box, but we know we do not have all the parts. If the ones we have are sufficient in order to conclude we are still a bit uncertain and that's why we continue the search in the sea as soon as the weather conditions improve.

HeliComparator

3rd May 2016, 17:14

@TS Yes I know. What would be interesting would be a long term analysis of all folk who work offshore to see, for those who died prematurely, whether death by helicopter was statistically significant compared to other forms of premature death. I can't help thinking it wouldn't be.

IMO it is the fear of a catastrophe rather than the probability of that catastrophe actually happening, that is causing stress and distress to offshore workers.

Pablo332

3rd May 2016, 17:15

Is this the gearbox?
Yes it is, the ring gear also appears to be missing. .The item to the right is a suspension bar.

Pablo332

3rd May 2016, 17:30

So the forward suspension bar pin is a larger diameter. If a smaller pin from a rear strut is inserted no one notices this quickly and possibly nappy pins it in place. That to me puts some major blame on engineering design for not making the smaller pin a longer length or different head shape or at least some obvious difference so the poor AME doesn't grab it by mistake. What a perfect fit for Murphy's law.
A catalog of errors would need to have taken place for the wrong size pin to be fitted as at some point someone would be faced with fitting a large pin in a small hole, penny should drop at this point.

If a pin was replaced and the wrong pin identified in the IPC it could be possible.

Someone would have commented that the FWD servo input required a lot of adjustment post MRH change.

Some very clunky take off and landings plus a 5R vibration should raise eyebrows.

Pablo332

3rd May 2016, 17:52

It looks like the epicyclic module is missing.

TylerMonkey

3rd May 2016, 18:09

I guess my fitting pins point is that obviously this has happened before from previous posts today.
That red flags the fact that recognizing two pin sizes are incompatible is not always easy and obvious or it would not have happened like it did on the non accident aircraft.
3 pins, 3 holes. 2 pins fit all 3 holes, one pin does not. Looks like an opportunity to make mistakes if you have extra pins on the bench and not just the 3 original.
Time for safety engineers to design more incompatibility into those pins.... shape, colour, who cares but fill the gap we are slipping through. Probably costs very little at the parts fabrication stage.

HBXNE

3rd May 2016, 18:12

Just a short down and dirty explaination of what remains of the lower gearbox. The epicyclic drive is missing. I tried to highlight with "Paint" 4 major areas. Red are the hydraulic servo lower support with the left and right rear supports showing the remains of the lower part of the hydraulic servos. The middle red circle is the forward lower hydraulic servo support. The 2 green circles are the left and right engine inputs. Lime green is the right hand transmission torque transmitter. The blue is the aft portion of transmission / fuselage "BBQ" plate. The purple is possibly the aft float support strut.

VortexRinger: I suspect you are right. I went back to Post #376 from "byeskille", thank you for posting the HD photos. The 2nd and 3rd photos zoomed in show the lower end of the "support rod" clearer. It is clearly not a transmission support rod. The clamps and what appeared to electrical wire on the strut gave me the impression that it was the rh rear trxm strut.
Marcus

VortexRinger

3rd May 2016, 18:38

HBXNE- The purple is the right hand rear transmission support strut.

I can see how it looks a suspension bar but Im pretty sure that's one of the Aft Float Support Struts! ��

cyclic

3rd May 2016, 18:51

Emergency Service Bulletin is out with regards to checking suspension rods, pins and attachment points.

dipperm0

3rd May 2016, 19:08

If a smaller pin is inserted in the forward fitting, pilots and hums will feel it as it has been written in a previous post.

If the normal pin is inserted, but not secured, as long as it stays in place, nothing could be felt, there is no play in the vertical/lift axis. but the second the pin moves out of the fitting in flight with roughly 11 tons of lift, the main rotor tilts backward and torn the epicyclic module.

victor papa

3rd May 2016, 19:18

Cyclic, any chance you can post the front page pls? Is the EASB only relevant to EC225 or 332's or all models?
Tks

VortexRinger

3rd May 2016, 19:20

http://www.airbushelicopters.com/techpub/FO/scripts/tipiFO_statDoc.php?news_id=16622&lang=en&file=EASBEC22553A058ENR0.pdf&r=c64956d8aab1ad1d383209ba93ca3048

cyclic

3rd May 2016, 19:20

http://www.airbushelicopters.com/techpub/FO/scripts/tipiFO_statDoc.php?news_id=16622&file=EASBEC22553A058ENR0.pdf&lang=EN&langtipi=EN

As HC says, you need a TIPI log-in to see it.

HeliComparator

3rd May 2016, 19:22

No good unless you have a TIPI login. Mine's expired.

Pablo332

3rd May 2016, 19:23

HBXNE- The purple is the right hand rear transmission support strut.

I can see how it looks a suspension bar but Im pretty sure that's one of the Aft Float Support Struts! ��
I think you are right P clips wrong colour for MGB area.

Apate

3rd May 2016, 19:25

Bizarrely is only applies to EC225 LP helicopters.

The Airbus legal and PR machine obviously doesn't want to shake up its other customers!

mekh

3rd May 2016, 19:40

here is the EASB

robsch

3rd May 2016, 19:45

http://ad.easa.europa.eu/blob/EASA_AD_2016_0089_E.pdf/AD_2016-0089-E_1

BTC8183

3rd May 2016, 20:05

http://ad.easa.europa.eu/blob/EASA_AD_2016_0089_E.pdf/AD_2016-0089-E_1

EASB 53A058..Interestingly reminiscent of issues with frame 5295 cracking and fitting loss of torque concerns from 10 years ago.Not,so far,a clear cut case of misplaced or incorrect suspension bar pins.

FNTC

3rd May 2016, 20:06

So Airbus decides to not ground EC225LPs, Shell Norway decides to stop all CHC Norway flights (with S92) indefinately, and now EASA sends out directive saying among other things to check suspension bar for "correct installation".

Starting to sound like maintenance error perhaps. Although this is only speculation at this point.

victor papa

3rd May 2016, 20:06

Tks cyclic, my TIPI currently dont incl 225 but got it!

Maybe this is not the only cause but the scary thing to all off us should be that all French helicopters fly using the stays and between 120, 130, 350, 365, 330, 332 and 225 how many hours were accumulated before now? Yes theres differences between pins vs bolts and nuts vs some split pin other baby pins etc but in principle they all the same for all these hours and years? Not a critisism or finger pointing, just a very sobering thought and reminder to stick to basics.

Very sad for the lives lost, 225 lost and for the engineers involved as I do not know how they are coping and hope they have support threw this regardless off the outcome!

Satcomm

3rd May 2016, 20:24

My thoughts as well Mitchaa! The following statement was from sbs.com

"We are as certain as we can be that a technical error caused the accident. We don't think it was due to human misinterpretations," the director of the board's aviation department, Kaare Halvorsen, told reporters on Tuesday.

Thank Kaare, that really clears things up .... throw a smoke bomb out there for now.

Never Fretter

3rd May 2016, 20:26

why the need to check MGB chip detectors, filter and HUMS data?

Perhaps they read your posts on the value of HUMS:E

charlieDontSurf

3rd May 2016, 20:39

Why does the EASA-AD include more checks than the bulletin from Airbus?

VortexRinger

3rd May 2016, 20:45

When you encounter a HUMS alert on certain MGB condition indicators, with for example a rising trend, the workcard will often tell you to check the chip detectors and the Oil filter.

RVDT

3rd May 2016, 20:54

If they believed the failure was to do with the suspension rods then why the need to check MGB chip detectors, filter and HUMS data?

Would seem prudent to me that while you are at it just check a few other things?

Looking for and being aware that strange or unusual things can happen is what helps to keep you alive in this business.

As Orville said to Wilbur "Assumption is the "Mother of all F*****ps"

Pablo332

3rd May 2016, 20:58

Apologies for my previous misidentification of the suspension bar in the first photographs as being the LH bar.

Identification was based on the EC225LP IPC which I now see is wrong.

Based on the Aircraft Maintenance Manual and the EASB it is in fact the RH suspension bar.

Just goes to show even the manufacturer has problems getting it right.

jimf671

3rd May 2016, 21:15

Am I right in thinking that there is an engine in the way of that front mounting? And is that the explanation for the timings in EASB?

n305fa

3rd May 2016, 21:16

Why does the EASA-AD include more checks than the bulletin from Airbus?

Probably because they feel that more checks are needed that those recommended by Airbus. All of which points to the consideration of a number of failure scenarios.

The EC225 and AS332L2 MGBs share a lot of commonality. The major difference is the flared housing on the 225 MGB vs the conical housing on the 332. The main module is very similar, and the epicyclic is effectivley the same on both types. Given the commonalities AS332 MGB/epicyclic failures shouldn't be discounted.

henra

3rd May 2016, 21:26

Ahem Satcomm, I am one of those "advisors" and let me assure you that in our company, we advisors present unbiased recommendations to management regardless of the current economic situation in the resource sector. In this particular case, our recommendation is NOT to fly this POS until cause is determined and rectified.

I hope you are seriously kidding. Being an advisor and making such biased and unverified statements doesn't bode well. That is profoundly unprofessional. If you were an advisor working for me your contract would be terminated here and now and I would send out a warning to any related/known other company about avoiding your service under any circumstance.

donut king

3rd May 2016, 21:32

Looks to me like a quasi disagreement between EASA and Airbus. EASA check MGB health and control rod attachment. Airbus check control rod attachment only. How could Airbus not consider MGB health given the lack of the epicyclic component? HMMM!

HeliComparator

3rd May 2016, 21:34

donut king

3rd May 2016, 21:43

Let's not confuse things. Not a control rod but a suspension bar.

DOH! Apologies...fingers faster than brain;) yes suspension rod.

SASless

3rd May 2016, 21:46

Auto Correct Strikes again.....Tarkay is in no ways a "Turkey"!

If one leg of the tripod breaks, it seems that the rotor will come off. I don't know, but having the entire rotor/mast held on with a single 12 or so mm pin seems a bit risky.

Interesting question!

Kinda reminds me of Transmission Mount issues on the early Jet Boxes!

zalt

3rd May 2016, 21:50

Let's not confuse things. Not a control rod but a suspension bar.

Correct.

donut king If you don't know the difference perhaps you should keep your speculations to yourself.

Being an advisor and making such biased and unverified statements doesn't bode well.

Oil company aviation advisors accept (or sometimes recommend) the aircraft their employer has contracted and the operators who fly them, so the insecure ones feel obliged to lash out at operator or OEM after an accident as a means of self-preservation (even when the oil price is $100 plus).

But then again this thread is populated by a lot of people who have made more comment on this topic than any other, ever, so he is unlikely to be who he claims.

henra

3rd May 2016, 22:03

Very sad for the lives lost, 225 lost and for the engineers involved as I do not know how they are coping and hope they have support threw this regardless off the outcome!

Yup. Horrible to think about what must go through the minds of the engineers involved especially given that maintenance error appears to be a very real possibility.

zalt

3rd May 2016, 22:09

given that maintenance error appears to be a very real possibility.

Maybe, maybe not.

Is it true that the person who started the online petition is a UK Independence Party candidate in Rochdale, Lancashire standing for election this week?

Kinda reminds me of Transmission Mount issues on the early Jet Boxes! Or indeed this problem of how the lift is transmitted to the fuselage on another type and cracks resulting in an AD: http://www.pprune.org/rotorheads/394474-s-92-gearbox-crack.html

Heliport

3rd May 2016, 22:36

Possibly.

Rochdale Online - Local Election 2015 (http://www.rochdaleonline.co.uk/news-features/elections/election-pitch/1024/david-barry-winder)

He says he works within the oil and gas industry.

ECE

4th May 2016, 01:07

Is HUMS a optional fit same as it is on a AW139? By optional I do not mean optional for the NS but optional from the factory.

Pablo332

4th May 2016, 06:00

Am I right in thinking that there is an engine in the way of that front mounting? And is that the explanation for the timings in EASB?
The FWD suspension bar and its airframe fitting are located in the No1 engine bay. It has a protective fire proof metal shield over it. The lower end of the bar and fitting are not visible in normal operation.

Checks of the fitting will probably require removal of the No1 engine.

The suspension bar pin is extracted through the firewall between the two engines once a panel has been removed.

Pablo332

4th May 2016, 06:14

Is HUMS a optional fit same as it is on a AW139? By optional I do not mean optional for the NS but optional from the factory.
I’m fairly sure HUMS is an option.

What annoys me is that HUMS support is also a very expensive option. An AH tax on safety.

In this day and age such support should be provided by the manufacturer as a matter of course without someone making money out of it.

9Aplus

4th May 2016, 07:55

My first hand experience is that HUMS installations and collected data is well within area of industrial secret, all against general safety of operations. That is the one and only reason why some OEM real time HUMS HW & SW is not already running now days in front of pilots at last on advisory level....

dipperm0

4th May 2016, 08:29

They have the bottom end of the forward suspension bar, I think they don't have the front suspension bar fitting yet.
If they find this fitting, and this fitting is un-damaged then 2 solutions:
Maintenance...
Pin shear under fatigue or corrosion or.... highly un-probable but...has to be checked

Apate

4th May 2016, 08:36

Ahh, dipperm0 is obviously the Airbus PR rep sent here to calm the waters :E

helili

4th May 2016, 08:55

According to the eyewithnessesand to the damage on the aircraft, i think it is not possible that the accident is caused by a broken suspensionbar/bolt/fitting, especially not the forward one.
The eyewithness told that the aircraft was sideway wobbling , then there came 3-4 cracksound(epicyclic/ringgear+3 suspension bars?), then the rotor an AC separated. The Rotor then flew/fell to one side(guess it has to do with the direction of rotorspinning) and the AC to the other side.

Her is a translation , and a link to one of the eyewithness:

« I was outside with my daughter, i heard the helicopter comming, so i picked her up and pointed at the helicopter.
I told my daughter «there is daddys northsea-helicopter»
After 3-4 seconds it started to wobble very much back and forth, and then there came 2-3-4 quite large «bangs», and i can see that parts are separating from the helicopter, most likeley the gear.
Then i see the rotor goes off the helicopter, and the helicopter fell to the ground»

He then says:
«The helicopter flew normal, then i saw it wobble and heard a «bang», after about two seconds i heard one more «bang» and then the helicopter goes straight to the ground»

Øyenvitne: ? Jeg så at rotoren falt av ? deretter gikk helikopteret i bakken - NRK Hordaland - Lokale nyheter, TV og radio (http://www.nrk.no/hordaland/oyenvitne_-_-jeg-sa-at-rotoren-falt-av-_-deretter-gikk-helikopteret-i-bakken-1.12924223)

If one of the supensionbar failed, i would think that the rotor would behave another way, it looks like it is ripped right of. The MGB module was also remaining on the AC

Pretty strange that the slidingcowling seems to have no big damage.

tarkay01

4th May 2016, 09:04

The FWD suspension bar and its airframe fitting are located in the No1 engine bay. It has a protective fire proof metal shield over it. The lower end of the bar and fitting are not visible in normal operation.

Checks of the fitting will probably require removal of the No1 engine.

The suspension bar pin is extracted through the firewall between the two engines once a panel has been removed.

Maybe it would be helpful to rename the "suspension bar pin" to "Jesus pin". Not as technically descriptive but maybe more appropriate to it's importance.

Also, the pins should be clearly marked so one can easily identify them. There seems to be at least one instance of an incorrect pin being installed which was caught on ground run up. Or redesign so all three are the same.

http://www.pprune.org/rotorheads/578298-ec225-crash-near-bergen-norway-20.html#post9364808

And, maybe an inspection procedure should be developed using a camera/bore scope so the engine does not have to be removed to inspect.

Pablo332

4th May 2016, 09:32

Maybe it would be helpful to rename the "suspension bar pin" to "Jesus pin". Not as technically descriptive but maybe more appropriate to it's importance.

Also, the pins should be clearly marked so one can easily identify them. There seems to be at least one instance of an incorrect pin being installed which was caught on ground run up. Or redesign so all three are the same.

http://www.pprune.org/rotorheads/578298-ec225-crash-near-bergen-norway-20.html#post9364808

And, maybe an inspection procedure should be developed using a camera/bore scope so the engine does not have to be removed to inspect.
Inspection of the Rod end hardware should be covered on installation by a duplicate inspection.

Post installation hardware can be checked for installation with a boroscope from the gearbox end going in through the Suspension bar hole in the rear firewall.

Torque checking of the suspension bar airframe fittings hardware will require MRH fairing /Engine/interior trim removal.

Cyclic Hotline

4th May 2016, 09:34

dipperm0 Pin shear under fatigue or corrosion or.... highly un-probable but...has to be checked

Nothing is improbable at this stage of the investigation. Improper material, heat-treat. process finish, anti-corrosion coating, or any number of other causes. But also failure originating from corrosion pitting or wear originating from either the pin, bar or airframe fitting. There are numerous potential root-causes and it is way too early in the investigative process to try and guess the cause. Guessing never resolved a single accident investigation.

I have great faith in the ability of the investigation to determine the probable cause based upon the resources of all the entities involved. My thoughts are with all the families, colleagues and employees affected by this awful occurrence.

Miles Gustaph

4th May 2016, 09:47

While the press briefing yesterday has ruled out human error by the pilots, does anyone know if CHC are looking after their engineers in Norway?

I imagine that having fitted a new gearbox only the day before that there may be some fairly distressed people working in engineering and I would like to think that there is support in place for them.

Solar

4th May 2016, 10:42

Question for those that actually know, is there any way to visually distinguish the different sized pins when they are installed? Different heads or pin orientation perhaps.

TylerMonkey

4th May 2016, 11:19

Whether or not this was caused by the loss of a pin it still shows the importance of making pin design changes that prevent future insertion of a pin in the wrong hole. 3 very critical parts that can be confused . . . it buggers belief.

It has been pointed out that a small pin in the larger strut hole should be obvious right away on power up / rotor lift or HUMS as happened previously, but that is still no reason not to ask for a redesign of the pins to avoid this possibility.

Edit : post 467 clears up this issue, 225 pins - all three lower pins have the same diam.

skadi

4th May 2016, 11:40

He then says:
«The helicopter flew normal, then i saw it wobble and heard a «bang», after about two seconds i heard one more «bang» and then the helicopter goes straight to the ground»

This timeline must not be real due to the difference between the speed of sound and speed of light. Altitude was 2000ft, so a minimum difference of 2 seconds!
I assume first the bang, followed by the wobbling motion?

skadi

G0ULI

4th May 2016, 11:43

Eye witness reports all seem to state that they heard bangs and then saw the rotor separate from the helicopter. Given that it would take half a second or more for the sound to reach the ground, it would seem likely that the bangs might have been a prelude to the rotor separation.

So what caused the loud bangs? An engine compresser stall, the gearbox starting to separate and rotor blades hitting the fuselage, suspension tie rods failing sequentially or some other cause?

Given that the sounds are described as loud bangs, it is unlikely to be the sound of metal failing directly, more likely engine related or the sound of impacting rotor blades as some internal brace or the gearbox housing failed.

The Norwegian investigators should be commended for allowing the press so much access to the wreckage and for the open nature of the investigation. That may upset some in the industry but there is a tremendous amount at stake and it is important that there are no allegations of collusion or cover up when the investigation is complete.

VortexRinger

4th May 2016, 11:57

All the lower pins are identical(fwd,LH and RH). The upper pins are a larger diameter and longer than the lower pins. They look very different. The lower pin has 2 flats on the head of the pin and the upper pins have 2 flats on a shoulder which protrudes from the head. The flats are there so you can rotate the pin to insert the nappy pins x2 in an acceptable position where they won't foul on anything.
You would only be able to mistakenly fit a lower pin in the upper (lift housing) holes! Not the other way around! It is unlikely any 225 engineer would not notice this on install or during subsequent after last flight inspections.

VortexRinger

4th May 2016, 12:00

I'm not sure this could be done anyway because the lower pins are too short. I have never seen this mistake made so don't know if it's possible!

P3 Bellows

4th May 2016, 12:06

The reports of 2 x loud bags would probably be the engines over-speeding or more specifically the free-turbines. With the head gone, there is no load, so they would run up and most likely experience a turbine burst.

I saw this in a Eurocopter demonstration video once and it is an explosion but contained within the reinforced engine casing. Not that the reinforcement would have helped in this situation sadly as bigger things were in play.

P3

mekh

4th May 2016, 12:23

the epicyclic module is here on the right side of the picture, so now we haven't sen any view of the conical housing and lift housing which are i suppose still attached to the mast...

TylerMonkey

4th May 2016, 12:27

Previous post 390 on thread gave the impression lower 3 pins not identical, that the two aft pins had a smaller diameter. It said small one was incorrectly inserted in a larger strut rod hole and gave a clunk noise on rotor lift. VortexR can you please clarify if the lower pins are the same diam ? TIA

VortexRinger

4th May 2016, 12:30

Same part number in the IPC for all 3 lower pins.

TylerMonkey

4th May 2016, 12:33

Check post # 390 , something doesn't add up.

helili

4th May 2016, 12:44

According to MMA the dimensions for the Suspension Bar bolt is the same upper and lower bolts (The outer diameter) 21,975 mm Min

The lenght is different.

Ref MMA 63 32 00 991

Helicopterfixerman

4th May 2016, 12:45

Please accept my apologies, everyone. My mind is obviously playing tricks. Vortex is correct, in that it is the upper pins that differ from the lower ones. The incident was also on a 332L, so the whole thing may be a red herring, particular if as Vortex said the pin is too short for installation in the incorrect position.

However, I confirm again, the smaller diameter pin has been inserted, and locked, in the wrong fitting (on a 332). It was not noticed by duplicating engineers. The first hint of something wrong was when the aircraft was powered up.

It is interesting that the ASB/AD require both the pins and the fitting attachments to be checked. Might this indicate that the suspension bar (at least one) has departed the aircraft but it is unknown whether it was via a pin failure/installation error or a fitting attachment failure/installation error.

I had heard a rumour that the forward fitting was replaced recently. Wholly unsubstantiated rumour.

Again, I'm not suggesting that any of this is the cause of the accident, but it is possible.

Apologies again.

VortexRinger

4th May 2016, 12:47

We always keep the pins in the same position after removal anyway. I've never noticed any difference in diameter between them. This is confirmed by the IPC. All three pins are the exact same p/n.

TylerMonkey

4th May 2016, 12:48

Thanks again, excellent info.

Helicopterfixerman

4th May 2016, 12:56

Vortex. Yes, 225 must be different from the 332. I think this error arose from a replacement pin being obtained from stores, but the incorrect one being ordered.

BTC8183

4th May 2016, 12:57

Thanks again, excellent info.

The 332 has two small diameter pins on aft suspension bar lower positions.The Fwd susp bar pin on 332 is a larger diameter. Remember 225 is 11000kg mtow, while 332L 8600kg and L2 9250 kg. Suspension bar pin dia went up with weight.

Helicopterfixerman

4th May 2016, 12:58

Thanks BTC.

SMW72

4th May 2016, 15:47

We always keep the pins in the same position after removal anyway. I've never noticed any difference in diameter between them. This is confirmed by the IPC. All three pins are the exact same p/n.

That's right. The 332L1 have larger diameter pins on the fwd strut. Not on the 225

VortexRinger

4th May 2016, 18:04

Apologies for a mistake in a previous post 460.
I can confirm (physically) that the 225 upper suspension bar pins are the same diameter as the lower pins. There is no difference in diameter between upper and lower pins. The lower pins are shorter in length than the upper pins.
I too fell foul of confusing the AS332l2 and EC225!

ukv1145

4th May 2016, 18:41

Ok so a few mistakes and confusion about the suspension bar setup on the forum. Is this indicative of the possibility of confusion/mistake when actually presented with the aircraft? Especially if you have both types on your license or in the hangar? Or is it very obvious when you have the parts in hand? I suspect it is relatively Murphy proof and something has mechanically failed rather than been incorrectly assembled.

Never Fretter

4th May 2016, 18:47

So all the people who said the epicyclic module wasn't visible, just hadn't looked hard enough.

And people with a clear memory of the pin arrangement were wrong.

:D:D:D:D:D:ugh::ugh::ugh::ugh::yuk::yuk::yuk::yuk::yuk:

But hey that won't stop people second guessing and pontificating I guess.

Apate

4th May 2016, 19:12

hence why the CAA classed them as 3 different types.

Which CAA? Certainly not the UK CAA. They are variants of the same type. They share a common certification basis under EASA, refer to the TCDS.

From a pilot licensing perspective they are all variants i.e. one entry on you licence covers all variants. Refer to the EASA OSD for more information.

Never Fretter

4th May 2016, 19:41

Mitchaa

Do you seriously think that losing one of the three attachments transferring the load between rotors and fuselage would not lead to instant destruction? Dis you really say Airbus need to prove Newton is right when you realise you are not?

And by the way have you been deleting posts? Why would that be?

Apate

The 330 and 332 were added to the EASA TCDS of the 225 2 years after the 225 was certified (as a new type). The 225 certification basis was JAR-29 as of 1999 albeit with a very small number of exemptions and deviations.

RVDT

4th May 2016, 19:50

Never Fretter,

You beat me to it - thanks.

spectral

4th May 2016, 19:59

The 3 pin and the 3 fix point of suspension bar is definitely different on each version L1 L2 and 225 and this point is clear....

at 140knot if you loose one suspension bar you take a tragically unbalanced on main rotor and this come out instantaneously and it's true for every helicopter....

And stop the comparaison with 225 and L2 the MGB is not the same the material inside is not the same.....

And you cannot discuss about the 225 without talk of this brother the 725 same MGB engine Rotor is exactly the same in military versions and sent in Afghanistan with shield 450kg, 2 machine gun, 1000L extra tank, 2 gunner , 8 commando it was so heavy he cannot take off normally, only running due to the weight and the altitude 2400m , for pick up the guy on ground he land only on top of hill for take off with the slope, it's was every flight at 100% of this capacity and he have never crash....

At this condition it's a other thing that to do a taxi at 3000 feet..... We are far of the limit of the aircraft...

And in every manual of human factor the mistake machine is only the human....

The torque need to be checked on suspension bar every 750h but do at 500h or every time the engine one is remove and that happens commonly...

Now because for many people the C C1 L1 L2 225 is only the same aircraft the super puma, how many millions hours is flying and how many time this problem appear????
only two time at this day one is REDL but it's maintenance problem the gear box was "saised" because the alarm was inhibited and the oil not drain result corrosion and one gear crank, block the main gear box and the rotor head came out with the speed...

And this one....if the EASA ask for check this part is certainly because something is missing or not clear...and if Airbus decide to take the risk to authorize the 225 at fly again maybe he think the design it's not the problem on this crash....

VortexRinger

4th May 2016, 20:00

Goes to show..never trust your memory!

henra

4th May 2016, 20:01

I honestly think we are all clutching at straws with this suspension rod pin theory. I just can't see that a single failure of a pin would cause the head to rip off instantaneously with no warning.

Did you really understand the MGB/MRH setup of the EC225?
Losing one suspension bar is highly likely to be terminal. Very quickly for that matter. Depending on how the bar came loose very possibly without much if any warning.
Someone called the bolts "Jesus bolts". I guess that nails it.

Lonewolf_50

4th May 2016, 20:03

@Never Fretter: given that each of three mounts (well, six, pins at each end) presents to the design team "catastrophic if it fails" (since the design team have to look at all loads and failure modes) I suspect that a substantial safety factor was given the pins' design/dimension.
If I understand the way they attach correctly, the pins would fail in shear if they fail at all. (If I misunderstand the attachment method, apologies).

Two previous points that seem not to have been later corrected are:

One of the pins is in a hard-to-get-to, hard-to-see place once installation is complete. Question is: "What is the inspection interval for condition/corrosion, etc for that mounting pin." (Since you have to get around the engine, is it a time consuming inspection procedure?).

Corrosion: I dont' know what the pins are made of, but I'll guess it's a hardened steel. How much history does this fleet have (I am asking about all of the ones using this particular mounting pin mentioned above, not just one company's) of having to replace a pin during service due to corrosion discovered during an inspection or otherwise uncovered?
My question is in part drawn from these helicopters operating in the maritime environment (oil rigs) and my own experience with the never ending corrosion war when operating on a ship with a helicopter.

@henra: nice pun, albeit tragic.

ericferret

4th May 2016, 20:16

From a maintenance point of view the Puma family falls into four separate groups.

330, 332L/L1, 332L2 and EC225.

These are the division lines where it is considered that a sufficient difference exists as to require a separate type rating for maintenance purposes.
This is defined by EASA regulations specifically Part 66..

So from a maintenance perspective North Sea Tiger is correct.

Pablo332

4th May 2016, 20:35

Anyone got a link to a photo that shows the epicyclic or flared housing on the recovered parts?

Apate

4th May 2016, 21:09

The 330 and 332 were added to the EASA TCDS of the 225 2 years after the 225 was certified (as a new type). The 225 certification basis was JAR-29 as of 1999 albeit with a very small number of exemptions and deviations.

Sorry, you couldn't be more wrong if you tried! For a start why would an older variant be added retrospectively to a new type certification?

The 225 was never a new type. As an example it would not have been allowed to gain the exemptions and reversions to Jar 29 Amdt 1 if it were a new type.

Airbus made a conscious decision to not certify as a new type, driven primarily by cost (see above exemptions and reversions!).

robsch

4th May 2016, 21:16

Is it the epicyclic that is in front of the MGB in this picture?
http://bt.mnocdn.no/incoming/article3590196.ece/ALTERNATES/w2048c169/IMG_6661.JPG?updated=030520161246

robsch

4th May 2016, 21:19

Close up picture.

Never Fretter

4th May 2016, 22:22

No theories. And no fantasies like some.

Quote:
The 330 and 332 were added to the EASA TCDS of the 225 2 years after the 225 was certified (as a new type). The 225 certification basis was JAR-29 as of 1999 albeit with a very small number of exemptions and deviations.
End Quote

Sorry, you couldn't be more wrong if you tried!

All factually correct. If they don't suit your irrelevant theories that's not my problem.

XV666

4th May 2016, 22:30

You can see it in post 491, to the right of the chap in the blue overalls right leg lower down, grey casing. There was a much clearer picture than that earlier but it's gone now.

This one, I think?

G0ULI

4th May 2016, 22:47

There seems to be the assumption by some earlier posters that improved vibration monitoring techniques might have identified an impending failure and prevented this accident.

I submit that while vibration monitoring is a good technique for analysing rotating components, it is possible for static components such as a gearbox casing to fail without any vibrational warning.

Dye penetration tests and X-rays prove only that a component is servicable at the time the test was carried out. A slight misalignment or incorrectly torqued bolts during reassembly or maintenance work at a later date could cause stresses that initiate a crack that then propogates without any sign of problems until the component suddenly fails in overload.

This process of fatigue cracking was first identified during testing after crashes of early Comet aircraft. Repeated stress allows seemingly insignificant flaws to grow over a period of time until sudden failure. A common factor in all the Comet crashes was that they all occured without warning. A redesign fixed the problem, but public faith in the aircraft was lost.

Testing and monitoring programs are a lot more stringent now but it seems that two nearly identical rotor separations have happened, although the exact root cause in each case is still to be determined.

Better vibration analysis and HUMS systems are probably not going to be the answer if the parts that fail are not actually moving, just providing a support structure.

henra

4th May 2016, 23:02

It's your opinion (along with Henra) that a single pin failure would cause instantaneous detachment of the main rotor head but you have absolutely nothing to back your opinion up with in the way of facts. No warnings, no RTB issues, no HUMS issues, no vibration issues?

No, I'm not ruling out a failure in the epicyclic module. I simply don't understand why why you are so desperately panicking to exclude possible causes and jump to one particular cause?!

Simply give the experts some time to find out what caused this horrible crash. What is the benefit of re-assuring yourself that it was one particular cause while still lacking sufficient and important information ?

Outwest

4th May 2016, 23:13

No, not instantaneous failure, I don't believe it.

I agree. What safety factor do you think EC would have built into those suspension bars? Double, triple? Meaning that if the design gross weight is 11000 KGS how many G's of loading would they design it for? 3 G's? 4G's? Look at what Spectral has described how the 725 is operated.

So with that in mind and knowing the load capabilities the other 2 bars must have, would a very slow decent on an a/c relatively lightly loaded have such a catastrophic failure with no warning even if and I do mean IF one bar failed?

Seems pretty hard to believe, for me who has zero experience/knowledge with either design or maintenance of a 225.

Heliice

5th May 2016, 00:03

If you ask me I an not imagine that the aircraft was designed to fly without a suspension bar, rather than say , without one main rotor blade . . .

Just the same would happen if you broke one suspension link doing 100km/h with your car, the rest of the links are not made to take up the increased load and your wheel is likely to break of and/or cause major control problems.

If the front bar came loose the gearbox would probably tilt backward and the airframe pitch down to the degree that the MRB would come in contact with the tail within a split second ?

Of course all of the above are pure speculations from my side.

jimf671

5th May 2016, 00:06

Outwest, I think you are underestimating the forces generated by an out-of-balance mass rotating at considerable speed and in the process of losing control inputs.

Outwest

5th May 2016, 00:12

jimf, why would it be out of balance?

Heliice

5th May 2016, 00:23

Outwest : because a rotor head/gearbox/airframe suspended by only two out of three suspension bars has negative dynamic stability.

Outwest

5th May 2016, 00:47

Outwest : because a rotor head/gearbox/airframe suspended by only two out of three suspension bars has negative dynamic stability.

Not sure what negative dynamic stability is.... But jimf said "balance" and I agree that the forces generated by an out of BALANCE are extreme such as losing a blade.

I have a good friend who lost about 6 feet of an S61 blade and although the result was not pretty, they all survived and the MGB/rotor head stayed attached.

I will eat crow if it is proven that the failure of one suspension bar/pin caused this, but until then I just can't believe that was the cause.

Heliice

5th May 2016, 01:29

Outwest : Imagine a three legged sling holding a load. If one leg(forward) breaks the load(airframe) will shift and find a new, neutural position(pitches forward). If the force holding the three legged (now two) legged sling load up(spinning rotor head) will also find a new netural position (tilts backwards). The negative dynamic stability of this configuration is dynamicly unstable and greater and greater oscillations will likely be the result.
Like I explained previously chances are that one would have the main rotor blades strike the tail. All this would happen almost instantaniously with disastrous consequences.
On top of this you will have forces such as, added drag of the airframe, the lift of the spinning rotors and blowback of the disc adding to the already hopless equation.

Loosing a part of a blade is nothing compared to loosing one of three suspension bars (not that I would like to try loosing part of a blade . . .). My chief pilot told me a story today about when one of four suspension bars on the 206LR broke many moons ago, scary stuff . . .

Outwest

5th May 2016, 01:45

Loosing a part of a blade is nothing compared to loosing one of three suspension bars

Really???

My chief pilot told me a story today about when one of four suspension bars on the 206LR broke many moons ago, scary stuff . . .

I'm sure not, but did half the MGB and the rotor system depart?

As I said before if this is proven that one suspension bar caused this I will eat crow.....but until then, I have said all I am going to on this.

Heliice

5th May 2016, 01:53

There is a big difference in having four vs. three bars. With four bars and a whole lot of luck one might be able to tell the story if one breaks. With three bars and one of them breaks I doubt one could :(
You could just find a piece of string and try the theory by hanging something from it in a four legged sling and then cut one sling at a time and see how the load shifts. That should clarify things.
Disclaimer : I am no engineer, just a heli-driver and hobby (car)mechanic, I will stand corrected :)

aheoe26104

5th May 2016, 02:15

In his debate about the suspension bars, the eye witness described an oscillation before the loud banging sounds (3 or 4), then parts coming off and then the rotorhead departing. What is the significance of this? Well, forces many times more than the 2.5 g (for example) that the helicopter was designed to withstand. If these oscillations were the result of a support bar or pin snapping as the possible theory would suggest, then the remaining two bars are now dealing with angular forces they are not designed for and not capable of coping with, including the mounts to the airframe. The bars are able to carry the load if the load acts in the direction of the bars and the mounts, but if you put a twisting force on them (to the magnitude of multiples of 9t) then I will guess they will fail.

In an instant.

The Bartender

5th May 2016, 02:29

Don't forget that light travels a lot faster than sound. Even while standing directly below the helicopter (minimum distance), the delay on the described "bangs" will be almost two seconds.
The sound the witnesses heard could easily be the start of the event, but because they were already watching the helicopter from a distance, see the results before hearing the initial event, screwing up the timeline of things.

riff_raff

5th May 2016, 02:30

The tension struts are not the only structural attachments for the MRGB. There are usually other attachments at the base of the housing. The tension struts connecting the collar at the top of the housing to the airframe are mainly used to minimize bending/distortion in the housing due to out-of-plane rotor mast moments, but they also take vertical rotor lift forces. Attachments at the housing base perimeter are used to handle in-plane rotor moments.

The tension strut arrangement is more weight efficient since it allows the housing structure to be made much lighter. Isolating the housing structure from most of the bending it would normally experience significantly reduces misalignment of gear meshes and rolling element bearing contacts.

Here is a nice photo (https://i.ytimg.com/vi/XUi_KMZgWJE/maxresdefault.jpg) of the tension strut and collar attachment on the H160 MRGB.

TylerMonkey

5th May 2016, 03:06

I noticed an item in my blow up of this photo and wondered if anyone familiar with the rotor head has an idea of what it may be. Could be a spring pin possibly ?

http://i86.servimg.com/u/f86/11/94/64/62/hubpin10.jpg

ECE

5th May 2016, 05:09

Helicopterfixerman

5th May 2016, 06:51

ECE is correct. It's one of the nappy pins that secures the MRB bolts.

Variable Load

5th May 2016, 07:19

I don't wish to deflect the discussion too much away from the accident, but there was some debate about the certification basis of the EC225 earlier in the thread.

Having worked closely with Eurocopter in 2004 and 2005 evaluating the EC225, I can categorically state that the EC225 has always been treated as a variant of the older Puma and Super Puma family. The initial EASA certification on 27 July 2004 was via a TCDS that also contained the SA330 and AS332L/L1/L2.

From a pilot licence perspective, it too has always been treated as a variant under EASA. Although if you were to speak to a CAA FOTI who was involved in the development of the Operational Suitability Data document, he would probably state that it should have been classed as a different type.

I wouldn't read too much into the lineage of certification, as it is quite common. Sikorsky have done it with the S76 family. Boeing have done it with extensively with the B737 and B747 models. At the end of the day why go to the expense of completely re-certifiying elements that were certified on a previous variant!

Never Fretter

5th May 2016, 07:31

I don't wish to deflect the discussion too much away from the accident, Agreed, however I should have posted the link: TCDS (https://www.easa.europa.eu/system/files/dfu/TCDS%20EASA%20R%20002%20Airbus%20Helicopters%20SA330-AS332-EC225%20Issue%20%2015.pdf)

Issue Date Changes
Issue 01 27 July 2004 Initial Issue; EC225LP model type certification
Issue 02 21 April 2006 Legacy Models added (SA330 and AS332)

Before 21 April 2006 the 330 and 332 were on a DGAC Type Certificate and TCDS.

I wouldn't read too much into the lineage of certification, as it is quite common. Sikorsky have done it with the S76 family. Boeing have done it with extensively with the B737 and B747 models.

Agreed.

Anyone who treats 330/332/225 as one type should also treat it's service experience as one type (arbitrarily looking no further back than 2009, say, is just being disingenuous).

henra

5th May 2016, 08:54

I agree. What safety factor do you think EC would have built into those suspension bars? Double, triple? Meaning that if the design gross weight is 11000 KGS how many G's of loading would they design it for? 3 G's? 4G's? Look at what Spectral has described how the 725 is operated.

Still not saying that loosing one suspension was the cause of this crash but if you would loose one suspension bar and especially if it was the longitudinal one the result would be a tilting of the rotor disc axis against the movement of the helicopter. Imagine having a chair with three legs. Guess what happens if one of those three legs brake. You end up on the floor, no matter how strong the remaining two legs are.
The only difference the strength of the remaining bars would have made in this case is that the rotor would have sliced through the rear fuselage/tail and stayed attached by the remaining two bars to the remains of the helicopter while tumbling down to Earth.
Now, why would the head shear off completely?
If the loss of the forward suspension happens at cruise speed resulting in the rotor disc tilting backwards the resulting g- load would be pretty high (up to the instantaneous Stall limit of the rotor which at 100% RRPM would surely be >>4g) and would have to be taken by only 2 remaining bars. Therefore especially losing the front suspension would very likely result in very quick separation of the whole head.

So with that in mind and knowing the load capabilities the other 2 bars must have, would a very slow decent on an a/c relatively lightly loaded have such a catastrophic failure with no warning even if and I do mean IF one bar failed?

As said that would be simply the consequence of the rotor disc axis instantly tilting to the rear (looking at the geometry of the suspension points probably ~30° from neutral) and building up massive g loads very quickly and without any chance to counter. The resulting loads on the remaining two bars would be massive and that is even without considering the rotor slicing through the fuselage/tail.

Pablo332

5th May 2016, 09:00

Still not saying that loosing one suspension was the cause of this crash but if you would loose one suspension bar and especially if it was the longitudinal one the result would be a tilting of the rotor disc axis against the movement of the helicopter. Imagine having a chair with three legs. Guess what happens if one of those three legs brake. You end up on the floor, no matter how strong the remaining two legs are.
The only difference the strength of the remaining bars would have made in this case is that the rotor would have sliced through the rear fuselage/tail and stayed attached by the remaining two bars to the remains of the helicopter while tumbling down to Earth.
Now, why would the head shear off completely?
If the loss of the forward suspension happens at cruise speed resulting in the rotor disc tilting backwards the resulting g- load would be pretty high (up to the instantaneous Stall limit of the rotor which at 100% RRPM would surely be >>4g) and would have to be taken by only 2 remaining bars. Therefore especially losing the front suspension would very likely result in very quick separation of the whole head.

As said that would be simply the consequence of the rotor disc axis instantly tilting to the rear (looking at the geometry of the suspension points probably ~30° from neutral) and building up massive g loads very quickly and without any chance to counter. The resulting loads on the remaining two bars would be massive and that is even without considering the rotor slicing through the fuselage/tail.
What’s missing from your scenario is the massive cyclic input from the FWD servo as it goes to full extension.

Variable Load

5th May 2016, 09:22

Thanks NF, I never thought to look at the change record!

My memory is a bit vague but there must have been a tie-up between the original EASA EC225 TCDS and the "Puma" JAR certification, as my written brief from 2005 does state that it was a variant of the AS332L and L2. Perhaps the TCDS contained a written cross-reference?

I've tried to find a copy of the original TCDS but failed.

However as discussed, it is of little consequence, other than if there are common parts or carried across design logic with previous models then once we know the root cause of this accident the ramifications could be wider than just for the EC225.

Time will tell - hopefully soon!

henra

5th May 2016, 09:38

What’s missing from your scenario is the massive cyclic input from the FWD servo as it goes to full extension.

Agreed.
Not sure it will change sequence and severity of events too much, though.

cteneto139

5th May 2016, 10:25

Last Airbus issue is suggesting a video camera installation on the cockpit. Anyone else see that?

squib66

5th May 2016, 11:04

My answers to those questions would be...

Mitchaa, no your speculations would be...

A quick google doesn't bring anything up of any accident being caused by suspension bar failures.

Every type of accident has to have its first time. This might be a first but it might not be.

Also don't confuse failures that cause accidents with secondary failures caused by accidents.

only the investigators know

They have the epicyclic in the hangar but we haven't seen any evidence to suggest they have the flared housing or the shaft that sit on top/mate into the epicyclic.

So why do you think you can second guess them looking at what's in the newspapers? No need to answer. That is a rhetorical question!