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Bristow S76 down in Lagos discussion (Not condolences)

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Bristow S76 down in Lagos discussion (Not condolences)

Old 16th Feb 2018, 03:09
  #141 (permalink)  
 
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Originally Posted by Copterline 103
gulliBell:


Your theory is naive.....
You're barking up the wrong tree. The pilots didn't do the RFM mandatory after-start hydraulic checks ELEVEN TIMES in the previous 14 engine starts. Pilots who don't do the required flight critical checks, or who do them but don't understand what they are doing or why, are the naive ones. Not me. Whilst the stick jump check, even if done properly, might not have revealed the leaking hydraulic actuator immediately prior to the accident flight (because both sides of the faulty servo were leaking about equally), by not doing the check they certainly missed an opportunity to discover the problem. And through the history of that servo being installed on that aircraft, I find it impossible to believe that at some point in the past, as the servo condition deteriorated over time, that not a single after-start hydraulic check revealed any problem. That servo had been leaking for a long time, the hydraulic fluid had been contaminated for a long time, yet nobody knew. All because proper procedure hadn't been followed.
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Old 16th Feb 2018, 06:02
  #142 (permalink)  
 
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Looking forward to see Bristow Helicopter’s accident 12th of August, 2015 accident report why the S76C+ was spiraling and acting precisely like COPTERLINE 103 and what was the reason for the second accident when Bristow Helicopter S76 become unflyable 3rd of February, 2015.
There are some people who know what they are talking about, and some relevant facts, and some that don't - I'm afraid you fall into the latter category.
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Old 16th Feb 2018, 06:29
  #143 (permalink)  
 
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Copterline 103
I was in Nigeria on February 5, 2015. What “accident” with a 76 happened at that date?
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Old 16th Feb 2018, 06:45
  #144 (permalink)  
 
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Link

I think he means the “water landing.”
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Old 16th Feb 2018, 09:41
  #145 (permalink)  
 
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Originally Posted by Nescafe
I think he means the “water landing.”
....good grief, ditching because of an AFCS problem....lucky they had a hero pilot to save the day.
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Old 26th Feb 2018, 14:05
  #146 (permalink)  
 
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Originally Posted by gulliBell
You're barking up the wrong tree. The pilots didn't do the RFM mandatory after-start hydraulic checks ELEVEN TIMES in the previous 14 engine starts. Pilots who don't do the required flight critical checks, or who do them but don't understand what they are doing or why, are the naive ones..
Dear gulliBell,

First of the all I would like remind you that we had met September 13th, 2006 at Sikorsky S-76 Operators Conference. I know your identity and to whom you are working for. I’m the guy who has been able to see behind to the curtains by reading thousands and thousands Sikorsky’s internal documents related to the S-76 Servo Actuator. In addition, I have had an opportunity to read thousands and thousands of internal Sikorsky’s emails, emails between HR, FAA, NTSB etc. In these emails you have been partly involved as a receiver, sender of by cc. For example, I have seen 1445 different emails to and from FAA’s Kirk G. between SIK, HR, NTSB and FAA. It might be that I’m not barking up the wrong tree?

You should be more precise about Copterline 103’s mandatory after-start hydraulic checks allegation. The truth is that you should separate engine starts and actual number of flights where the engines have been running after 18 to 20 minutes flights. During these 14 flight sequences there has been three engines start-ups. The S-76 RFM mandatory after-start hydraulic checks are related only to the engines starts, not to the flight sequences where the engines will be ground idle during the helicopter ground time. The Copterline 103 Commander was type trained by Flight Safety West Palm Beach, with an earlier significant experience as an Bell 412 EP Commander of Finnish Border Guard Search and Rescue unit.

What about your reference to all proper procedure hadn’t been followed. Your arguments about missed after-start hydraulic checks, stick jump tests are improper and prejudiced to reach your intention and leads the dogs barking the wrong tree.

About your argument of “all proper procedure hadn’t been followed”. The Servo Actuator piston rework in Plasma Tech Inc. didn’t follow the FAA accepted overhaul instructions. The composition of the plasma that was used in Copterline 103 Servo Piston’s overhaul was wrong. The overhaul instructions which were used issued by HR was never accepted by the FAA. The maximum accepted thickness of plasma coating clearly exceeded the maximum approved by FAA. Servo Actuator design in late 70’s didn’t take into account the oversized plasma thickness, didn’t take into account that the plasma’s aluminiun composition is less than accepted 20 % (accident servo piston’s plasma had only 10 % composition of aluminiun) and Servo Design allows a malfunction which will block the MCV’s return ports (C3 ports) and the helicopter caution and warning system doesn’t detect any defect. This malfunction will lead to the situation where the helicopter will become suddenly unflyable….

This all was informed to Lockheed Martin Corporation at time when the acquisition process to acquire Sikorsky (due diligence) was still pending. The listed company Lockheed Martin Corporation’s highest level was informed for this possible flight safety concern which may have a type certification consequence. After evaluation where you have very likely participated, Lockheed Martin Corporation decided to proceed with the acquisition of Sikorsky Aircraft Corporation from United Technologies (UTC).

It looks that Sikorsky has passed the point of no return already on 25th of May, 1978 when the Servo Jam defect due to the plasma flakes was evidently detected by SIK. Also the consequences were evidently understood (loss of control of aircraft and fatal accident). If I’m right and if all the documents what I have been able to see are correct it might be that quite many involved entity have past the point of no return, not limited only present owner of the Sikorsky, Lockheed Martin Corporation and its shareholders. It looks that there is a high possibility that we are not far away from the time when the **** will hit the rotor. If this will make the helicopter industry to be more focused for aircraft safety and be more creditable. This will not be bad at all.

The documentation what I have been able to see is the ground of the origin of my thoughts.
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Old 27th Feb 2018, 00:06
  #147 (permalink)  
 
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Originally Posted by Copterline 103

...You should be more precise about Copterline 103’s mandatory after-start hydraulic checks allegation. The truth is ...
The truth is as per what was written in the accident report, which you've no doubt read. I've attached the relevant finding here, for those not familiar with it. Pilots must do the after-start hydraulics check, it's probably the most important check in the book. The accident report says it was only performed 3 times in the previous 14 engine starts.

And when you speculate about other S76 accidents that you suspect might be servo related (Nigeria, Indonesia), which everybody else knows had nothing to do with servo, just emphasizes my point. Barking up the wrong tree.

Guys, do your checks by the book, understand what you're doing, and why! In my experience teaching recurrent trainees, the knowledge level on this aspect is generally south of where it should be....I find it impossible to believe that after-start hydraulic checks would not have revealed the problematic servo in the accident aircraft at some point after it was first installed.
Attached Images
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Old 27th Feb 2018, 15:36
  #148 (permalink)  
 
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GulliBell, can you post a better picture of the section of the report you are referencing? I can't read what you posted. Thanks.
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Old 27th Feb 2018, 16:09
  #149 (permalink)  
 
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It's a thumbnail. Click it.
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Old 27th Feb 2018, 21:04
  #150 (permalink)  
 
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Originally Posted by Mast Bumper
GulliBell, can you post a better picture of the section of the report you are referencing? I can't read what you posted. Thanks.
Yeah, it's a thumbnail. Click it and it goes full screen.
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Old 27th Feb 2018, 23:33
  #151 (permalink)  
 
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Originally Posted by gulliBell
I find it impossible to believe that after-start hydraulic checks would not have revealed the problematic servo in the accident aircraft at some point after it was first installed.
The last sentence of the report section you’ve published, seems to disagree with you.
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Old 28th Feb 2018, 01:34
  #152 (permalink)  
 
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Originally Posted by HeliComparator
The last sentence of the report section you’ve published, seems to disagree with you.
No it doesn't.

That is specifically referring to the state of the servo at the time of the accident, because both sides were leaking about equally at that time. That faulty servo was on the aircraft for a long time, and over that time, with variance of wear in service and the rest of it, I seriously doubt that at all times during its in-service history that both sides were always leaking equally. Hence the after-start servo checks should have revealed a discrepancy at some point in the past.
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Old 28th Feb 2018, 11:45
  #153 (permalink)  
 
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BACK TO THE ROOT CAUSE...

Dear gulliBell,

Let's go back to the right tree. How can you explain the attached images of the Servo Actuator's pistons? How long do you believe the Plasma Flakes has been in C3 port? How do you explain that some of the plasma flakes have gone through the C3 port?

Just memorizing you..,.. you should be familiar with the following text:

“As indicated, we are aware of only four totalinstances of the defined failure mode. The summary of these pistons is asfollows (please note the first item listed was NOT chipped, however, it wasre-plasma sprayed in the same overhaul lot of 29 pieces that the second and thirdlisted items were also a part of – this is listed to show that we do no necessarilyhave an obvious lot problem – however,we may have a process related failure mode):”

These 29 reworked pistons went to the market 2003, with loss of Piston’s S/N because the original S/N of Piston was over coated by the plasma spray. This may be the reason why SIK can’t anymore identify and locate where these “failure mode piston are installed today”.


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Old 28th Feb 2018, 12:03
  #154 (permalink)  
 
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I seriously doubt that at all times during its in-service history that both sides were always leaking equally.
No doubt - but does it not expose the possibility that the test is not without fault?
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Old 28th Feb 2018, 12:55
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Originally Posted by RVDT
No doubt - but does it not expose the possibility that the test is not without fault?
If the pilots were only occasionally doing the required mandatory servo check - 3 times in the last 14 starts when the RFM says it must be done after every start - is indicative to me either of a lax attitude, or appalling lack of knowledge. There is no other way to dice it. One or the other being self evident lends the idea that when the check was actually done it may not have been done properly. I'd like to see the FDR data points on those 3 occasions captured when the check was done (if I recall, the resolution of the cyclic/collective position data is 4 samples/sec, which should be sufficient to confirm whether there was no delay between applying control inputs and isolating each hydraulic system).

There is no point doing the check if you don't do it properly. So do it properly. Don't invent your own way of doing it. The test is not at fault here.

Last edited by gulliBell; 28th Feb 2018 at 13:09.
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Old 28th Feb 2018, 13:07
  #156 (permalink)  
 
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Originally Posted by Copterline 103
Dear gulliBell,

Let's go back to the right tree. How can you explain the attached images of the Servo Actuator's pistons?...
I don't care about the photos. A bad servo was fitted to the aircraft, we know that. It shouldn't have gone undetected for that long. There were missed opportunities for finding it before it caused the accident. If the proper maintenance procedures were followed, and if the proper system checks were performed by the operating crews, then maybe we wouldn't be having this discussion.
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Old 28th Feb 2018, 13:25
  #157 (permalink)  
 
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Originally Posted by GoodGrief
It's a thumbnail. Click it.
Ahh, got it, thanks.
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Old 28th Feb 2018, 14:44
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Originally Posted by gulliBell
I don't care about the photos. A bad servo was fitted to the aircraft, we know that.

Dear gulliBell,


I have learn that you don't care about the photos. You remember well as you refused to see "erecting plasma flake in the C3 return port". You told me that you can't see anything wrong or anything unusual in the erecting plama flake in the picture. Do you still concur?


Servo Actuator was a good one but SIK was saving money by using old reworked pistons. The rework process was not at all a proper overhaul process. The SIK failed to follow FAA's approved overhaul instructions. The old plasma was stripped away by using a mechanical process despite of the approved chemical stripping process. This unapproved overhaul practice lead to the consequences where the diameter of origin of the piston became smaller and smaller after each rework turnaround. The accident servo actuators piston has been 9 times been reworked. The diameter of the origin of the piston was clearly less than the minimum diameter accepted by the FAA approved overhaul instructions.


This recycling of the used piston up to 9 times lead to the demand where the thickness of the plasma needed to be increased to reach the required final diameter of the piston.


The used plasma composition was not a proper and not as accepted by FAA's approved maintenance instructions. The approved composition should have been 80 % copper and 20 % aluminiun. The accident pistons and the whole patch of reworked pistons (which may still be in use and most likely are in daily flight operation) composition was 90 % of copper and 9,6 % aluminiun and 0,4 % titanium.


During the rework process the original S/N of the piston was over sprayed and due to this the mandatory requirement of Airworthiness which insists that aircrafts each component's or spare part's maintenance history must be reliably documented. Despite of the loss of this mandatory identification and tracking requirement all of the defected pistons patch were returned to the market by violating the mandatory airworthiness requirement.


SIK has had the knowledge of this serious flight safety issue already since late 70's but SIK decided to continue forward by passing the point of no return. SIK has had the knowledge that there has been "process related failure mode" during the overhaul process of the Servo Actuator Pistons.

FAA has this knowledge that accident helicopter servo actuator's pistons has been overhauled by violating the approved overhaul instructions. Also FAA has a knowledge of this piston's overhaul process has violated the approved instructions.


It is sad that the safety doesn't matter at all and everything will be hidden.


I have a capacity to prove the SIK knowledge. At the moment this issue is not only an issue of Sikorsky, it's now the issue of the owner of the SIK, the Lockheed Martin Corporation. My opinion is that Lockheed Martin's corporate culture derivates from past time Sikorsky's culture.


Every entity involved for the air safety, airworthiness has the proven knowledge of this above. I can now just wonder the consequences when the **** hits the rotor. It will bring up the question why the authorities let this going on. How many other lives must be lost?


Improper maintenance? What do you gullBell think about this Servo Actuator's overhaul process and SIK's violating of the mandatory FAA's overhaul instructions?
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Old 28th Feb 2018, 20:11
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Improper overhaul procedures etc.

I have open my files. One correction must be done:

The FAA approved overhaul instruction requires that the Plasma coating material should be Metco 445 (85 % copper and 15 % aluminiun).

The Tallinn University of Technology and NTSB came up with the same results of SIK used plasma composition. The accident servo piston plasma composition was Cu 98 %, Al 1,5 % and Ti 0,3 %. The other finding was that due to wrong plasma composition the plasma flakes doesn't decompose to the smaller pieces as planned.

By using the right material (Metco 445) the removing plasma flakes should not maintain the present size and the plasma flakes should be decomposed to the smaller and smaller pieces to avoid the C3 port obstructions. This is the knowledge what I, NTSB, FAA and SIK are sharing. This in no new news for any stakeholder.

SIK S76 HRT Servo Reliability Improvement Plan meeting on 15th Sep, 2006 has agreed that: "Chips/flakes have low likelihood of creating significant (>75%) blockage during 3000 TSO".

The type certification requirements requires instead of "low likelihood" to be "extremely improbable". This is an issue what Lockheed Martin Corporation is nowadays accountable as the TC Holder of S-76.

If more detailed information or evidences are needed, I'm more than pleased to show and provide it.

Please see the attached pictures of the plasma and plasma composition as an evidence of improper maintenance.
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Old 28th Feb 2018, 20:32
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All great and I admire your devotion, but totally irrelevant to the BHL incident in this thread and the HL one in Indonesia - I assure you!
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