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-   -   Bristow S76 down in Lagos discussion (Not condolences) (https://www.pprune.org/rotorheads/566059-bristow-s76-down-lagos-discussion-not-condolences.html)

N Arslow 17th Aug 2015 03:35

Off thread?
 
Are people on here just looking for an excuse to vent? I would say this is the wrong thread to do so. It seems more about the loss of two well liked and respected colleagues. Speculation, however couched in a round-about fashion, seems inappropriate to this thread.

No belittling of points being made but at this stage not too many seem relevant to this sad accident, certainly at this moment. Start some other threads and get things off your chest there.

Jay will have signed out the aircraft and would have expected to sign it back in - just as most of us do each day wherever we are, and despite all the whinges posted on PPRuNe.

Rest in peace, Jay - and also to those I did not know as well.

tasspook 17th Aug 2015 03:51

No venting going on here Mr. Arslow, just an observation of cold, hard truth and that truth is corners are cut in all too many places in the helicopter world. Ideally the investigation into this accident will be timely, thorough and devoid of meddling or undue influence from parties who may have something to hide.

FLYDHC8 17th Aug 2015 11:06

N Arslow is spot on, nothing to show that this accident was caused by management cutting corners or anything else for that matter. Let's wait till we get to know what actually happened.

Jimny 17th Aug 2015 11:32


Jimny, I am sure DB does a walk-around every flight .... he just doesn't climb up on top to re-open cowlings that have already been opened the previous day's post flight, and again in the morning and signed for by a qualified engineer
Ok fair enough, I came in a bit strong and as DB mentioned later on, I am not saying you should reopen everything again. But since I've actually seen a lot of older pilots just go straight to the pilot seat without even checking if the aircraft is still tied down I guess I'm a bit traumatised.


I have to say that I am a little baffled by some of the comments in respect of pre flight inspections. I can't work out how they relate to the accident in question.
Nobody said it did, the subject wass brought up and a small discussion arose from it.

I sincerly hope they find the cause to the accident soon.

Unfortunately I lost the link to the newspapper mentioning it but there was an article about witnesses in a nearby village seing the helicopter trying to land (or at least it seemed so to them) on roof tops before opting for ditching. Don't know how reliable the info is thou.

flyer43 17th Aug 2015 13:31

Eye witness reports
 
I wouldn't hold you breath regarding eye witness reports! The majority of these tend to be embelished for the media and are far from accurate representations of what actually happened.

Whilst some of the comments on this thread are worrying if they are true, let's all show respect the lives that have sadly been lost and not continue any speculation. Wait for the officical report!

Fareastdriver 17th Aug 2015 16:15

Kick the tyres; light the fires. Worked for me for forty-eight years.

chuks 17th Aug 2015 16:29

Nigerian eyewitness reports are only useful as a gauge of how imaginative your average Nigerian can be.

There was a report once of a missing 727 having been seen "hovering" over Murtala Muhammed Airport by some prominent God-botherer, and it was repeated so, verbatim, in the local papers. In fact, the aircraft had never got near the airport, crashing into a lagoon some miles away.

jesusnutt 17th Aug 2015 18:33

To which Oil Co was the 76 on contract?

HeliComparator 17th Aug 2015 18:50


Originally Posted by N Arslow (Post 9084603)
Jay will have signed out the aircraft and would have expected to sign it back in

That's funny, I have been a pilot in the industry for 35 years, captain for 30, and never ever signed an aircraft out. But then I suppose I don't have "still in the military" disease.

minigundiplomat 17th Aug 2015 20:14

Clearly not.

Just an inferiority complex.

Copterline 103 17th Aug 2015 20:48

Eyewitnesses vs. FDR / Banging sound/ Spinning left / MR RPM zero
 
Given by eyewitnesses statements should be treated with caution.
Trusted from information seems to a loud bang sound and helicopter spinning before hitting the water with M/R RPM zero or almost zero..
The best source of information is the FDR which explains in detail where it all began and where it all ended.
In my assessment, the FDR will indicate that the cyclic has become fully aft position, collective has risen to max top position within one second.
No warning or caution has existed when the situation has started. The first warning probably had been a low M/R RPM. This is due to the fact that the helicopter nose will rise up to 60 degrees (stalling and making a banging sound), banking 50 degrees to the left. Cruising speed 140 kts to zero will be lost in a second. Flight controls are stuck by one servo actuator which is stuck in fully extended position. (Sikorsky’s flight controls system has mechanical mixing unit. This mixing unit will reduce pilots work load by mechanical compensation to peals when the collective will be increased or decreased). When the collective is in a fully up position the helicopter mixing unit mechanically makes compensation and will put left pedal almost max left position (causing spinning to the left after helicopter has lost its airspeed).
The reason why helicopter is losing its M/R RPM it is most likely due to collective position which remains max up position due to 3500 PSI hydraulic pressure. Even both of Turbomeca’s ARRIEL 2S1 engines are in “fly-away emergency power” but engines don’t have enough power to maintain MR RPM due to collective remains in max up position. The crew doesn’t have any possibility to fight against 3500 PSI hydraulic power which is over controlling all controls keeping cyclic in full aft, collective max up and mixing unit is compensating collective position by taking left pedal almost fully down.
All this causes the Servo Actuator piston’s chipped plasma coating what will block Servo Actuator’s C3 return port (fluid) or both of C3 return ports. Servo Actuator system or system design does not recognize that the Servo Actuator has failed and there is not any auto function which will release affected servo channel. Servo Actuator’s design can’t recognize that servo actuator has failed and the whole Servo Actuator unit (two independent Servo Actuators) is out of control. During this situation there is no any Servo related cautions or warnings. This single defect will cause that the helicopter will be immediately unflyable.
It is clear that the transportation category’s helicopter type certification requirements requires that any single defect (e.g. chipping of the plasma coating) wouldn’t drop any offshore approved transportation category helicopter down. That's what has happened to us 10th August, 2005. Our helicopter s/n was 760512 (made 28 units before that Bristow’s s/n 760540). All information what I have received are supporting theory that “the most likely” this will be also the case in Lagos.
FDR's data will tell immediately what has happened.

In our accident August 10th, 2005 we lost 14 innocent lives.

212man 17th Aug 2015 21:21

Copterline, 'your' accident came quickly to mind when I heard of the initial witness reports, but please try and add credibility to your posts by getting the facts correct!
S76 hydraulic system is 3000psi, not 3500
The Copterline aircraft hit the water with 70+% Nr from about 5 times the altitude of 5N-BGN, so clearly this failure will not have resulted in zero Nr!



Originally Posted by Copterline 103 (Post 9085558)
Given by eyewitnesses statements should be treated with caution.
Trusted from information seems to a loud bang sound and helicopter spinning before hitting the water with M/R RPM zero or almost zero..
The best source of information is the FDR which explains in detail where it all began and where it all ended.
In my assessment, the FDR will indicate that the cyclic has become fully aft position, collective has risen to max top position within one second.
No warning or caution has existed when the situation has started. The first warning probably had been a low M/R RPM. This is due to the fact that the helicopter nose will rise up to 60 degrees (stalling and making a banging sound), banking 50 degrees to the left. Cruising speed 140 kts to zero will be lost in a second. Flight controls are stuck by one servo actuator which is stuck in fully extended position. (Sikorsky’s flight controls system has mechanical mixing unit. This mixing unit will reduce pilots work load by mechanical compensation to peals when the collective will be increased or decreased). When the collective is in a fully up position the helicopter mixing unit mechanically makes compensation and will put left pedal almost max left position (causing spinning to the left after helicopter has lost its airspeed).
The reason why helicopter is losing its M/R RPM it is most likely due to collective position which remains max up position due to 3500 PSI hydraulic pressure. Even both of Turbomeca’s ARRIEL 2S1 engines are in “fly-away emergency power” but engines don’t have enough power to maintain MR RPM due to collective remains in max up position. The crew doesn’t have any possibility to fight against 3500 PSI hydraulic power which is over controlling all controls keeping cyclic in full aft, collective max up and mixing unit is compensating collective position by taking left pedal almost fully down.
All this causes the Servo Actuator piston’s chipped plasma coating what will block Servo Actuator’s C3 return port (fluid) or both of C3 return ports. Servo Actuator system or system design does not recognize that the Servo Actuator has failed and there is not any auto function which will release affected servo channel. Servo Actuator’s design can’t recognize that servo actuator has failed and the whole Servo Actuator unit (two independent Servo Actuators) is out of control. During this situation there is no any Servo related cautions or warnings. This single defect will cause that the helicopter will be immediately unflyable.
It is clear that the transportation category’s helicopter type certification requirements requires that any single defect (e.g. chipping of the plasma coating) wouldn’t drop any offshore approved transportation category helicopter down. That's what has happened to us 10th August, 2005. Our helicopter s/n was 760512 (made 28 units before that Bristow’s s/n 760540). All information what I have received are supporting theory that “the most likely” this will be also the case in Lagos.
FDR's data will tell immediately what has happened.

In our accident August 10th, 2005 we lost 14 innocent lives.


cpt 17th Aug 2015 21:36

..... but if I remenber well, in the "Baltic sea case" there had been previous signs of an anomaly in the hydraulic system .... an uncommonly darker color of the hydraulic oil had been noticed, and a pilot returning from a technical flight reported having felt a very brief temporary blocking in the collective pitch without any other sign.

n1tut 18th Aug 2015 16:58

I have only just heard of the crash from this Forum six days after the accident, and saw no mention of it on the news in the UK. I flew 17 years for Bristow on the North Sea from Aberdeen, 13 of them on the S76.

However I am now 75 and was medically retired in 1993, so none of my colleagues are still flying. Although I did not know the two pilots my thoughts go to their family and friends, I had many nasty moments myself over the years, even more so during my seven years flying in the War in Oman, so count myself fortunate to have survived to retirement.

Cheers

David Duncan

tistisnot 19th Aug 2015 02:44

Moderators, please - Ramos has a valid point.

Is it not time to set up a public / group Facebook In Memoriam page where people could express their condolences, thoughts about crews / individuals whether death by natural causes or otherwise - instead of the families trawling through the immediate reportings and speculation here on the Rumour Network?

People would then be probably posting with their real names, instead of the anonymity many prefer here on this site?




A separate thread for condolences is here

Splot

Variable Load 19th Aug 2015 12:32

Until the course of the Bristow Nigeria accident is known, the Copterline accident is irrelevant to this thread and was well covered a long time ago in this forum.

Copterline 103 - if you want to discuss the OH-HCI accident please start another thread :rolleyes:

terminus mos 19th Aug 2015 12:33

I am very sorry for everyone affected by this accident. I won't pray for anyone because it doesn't work and I am an atheist.

PPrune forums, threads and posts have always been about expressing one's sympathies if one so wishes. But they have also been about speculation and rumour. We are Pilots, we are directly linked if not directly affected. Speculation is normal, occupies many crew room conversations and will always happen.

To try to shut it down here and limit threads and posts to condolences would stop many people reading PPrune.

Boudreaux Bob 19th Aug 2015 12:47

I distinctly recall a Bristow Pilot who always said the following Prayer just before hitting the Start Button.

"Oh Lord, Please forgive me for flying this Bell Built, Bristow Maintained, piece of ****!".

He is happily retired now.

I would suggest that is real evidence that Prayer does work.

Grunt92 22nd Aug 2015 20:20

Gentlemen, especialy, copterline 103, please do not speculate on previous accidents, after reading , Cl 103 ,s biblical speal, i realise he doesnt really know the S76 hydraulic and rigging system, leave that to the certified engineers, also please wait until the results of the invesigations are disclosed.
If at anytime , one of my pilots have wanted a cowling or panel opened I have always been willing to do this, and then ensured it was secured, as I had signed ,the pre flight inspection, and have always been part of a good and safe Flying and Engineering TEAM.
Engineers have coverals and opposing thumbs to climb around , pilots have sloppy links to fly with. Sad this has happened.
Safe landing to all.

pilot and apprentice 7th Sep 2015 18:10

One of the concerns is that, given where the accident happened, there may never be a true and full accounting of what really happened. We will see. I hope so. Unfortunately what I have seen happen before instills little confidence. (No, not a complete stab at Nigeria. The outside parties have been just as happy to let the truth die a whimpering death as any in country)

=========

Has there been any word put out at all? Even a very basic preliminary report would normally be released by now, would it not?


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