Bristow S76 Ditched in Nigeria today Feb 3 2016 [Archive] - Page 3

Copterline 103

21st Mar 2016, 20:54

@tgvbhy15
I'm very pleased to share my knowledge with everybody who is working with S76 series helicopters. I have had change to read documents which are not public documents. Due to this; my understanding for consequences and the root cause is so clear. I'm very disappointed to see how some of the interest parties are willing to misslead investigators, pilots and technicians to change the focus from actual root cause to the consequence.

For example the 12th August, 2015 the preliminary report of the accident, together with issued AD, changed the focus to the Control rod, the Control rod end and the locking nut. The finding was that the Control rod and the rod end have separated. A lot of noise was created to inspect if the locking nut is not in place and an AD and ASB were issued....it is like David Copperfield who makes you see what he wants you to see.

The Control rod and the Control rod end separation during the flight are almost impossible if the helicopter behaves normally. When the helicopter is behaving normally the flight controls work load (resistance load of flight controls, mixing unit, control rods) is only 5 lbf. This is due to the fact that the hydraulic power (Servo Actuators) is making the power work behalf of PF.

If you consider the fact that the Control rod tube and the Control rod end has come loose and entered through a thread. Everyone can make on evaluation that the 5 lbf work load is not enough to cause this Control tube and the Control rod end separation.

If you consider that if the case is that the flight controls are jammed and two dying man are fighting against jammed flight controls by using the power of adrenalin. You can only evaluate how huge the forces of the two dying man can achieve?

In the Baltic Sea accident the 10th of August, 2005 the Commander was able to bend the his control stick forward. The copilot together with the captain were fighting against jammed flight controls until they were able to brake the control tube and the control rod end which is connecting copilot's and captain's control sticks.

All of this (above) was verified from the FDR, CVR and by the physical evidences from the helicopter wreckage.

Even in the theory the possible missing locking nut has no influence on the strength of Control rod tube and the Control rod end. The locking nut is needed to secure that the length of the Control rod assembly will be fixed and any unplanned Control rod end rotation (bolt thread) could not happen which could change the length of the Control rod assembly. This only during the maintenance action when the Control tube assembly is disconnected for the helicopter. At time when the Control tube assembly is connected to the helicopter the Control tube and the Control rod end is not able to rotate because it is attached by the bolts in the both ends.

The conclusion is: the control rod assembly can't be separated by 5 lbf. work load but two dying man could have enough power to brake this Control tube assembly e.g. if the flight controls are jammed.

We have to memorize that the S76 series helicopters are or should be certified under the FAA's transportation helicopter category requirements?

Sanus

22nd Mar 2016, 11:24

Cop103 you mention many interesting things but surely even a first year metallurgist could tell the difference between a thread that has failed through looseness (chaffing and wear) and a thread that has suffered sudden shear overload? The latter would have rolled over thread crowns etc.

You are very cynical of the investigators but I cannot believe the NTSB and Nigerian AAIB would ever falsely manipulate evidence. Are you falling into the trap of trying to make the evidence match your personal theory?

ericferret

22nd Mar 2016, 14:35

The lock nut does more than prevent rotation of the rod end. To assemble anything there has to be a clearance unless you are assembling using an interference fit. The interference process is not usable for a rod end that requires adjustment.

The second function of the lock nut is to draw the male and female threads together and prevent movement and fretting.
If the nut is loose there will be motion between the two threads dependent on the tolerances that the threads have been manufactured too. More than possible that the female could be at maximum and the male at minimum. The further out that the rod end is adjusted the less support there will be and the less resistance to fretting.

If this condition existed for an extended period then the threads will gradually be destroyed and the rod end released. If the tube is aluminium and the rod end steel then this process will gradually speed up. I do not know what the S76 tube is made from but the eye will be steel and as the rod is below the servo a good chance it will be aluminium.

I would conclude that there is a good chance that the rod end was loose for some time leading to excessive thread wear and release of the rod end.

Copterline 103

22nd Mar 2016, 20:24

@Sanus
You are very cynical of the investigators but I cannot believe the NTSB and Nigerian AAIB would ever falsely manipulate evidence

My experience since last ten years with 60.000 non-public accident related documents has opened my eyes. My opinion is that the NAIB is the most accountable of these related parties.

Sanus don't be naive, please!

The FDR, FDAU and cockpit camera's (CIR) data has been lost! Think about this. Maybe the hot and high conditions has destroyed this data of HDG, PITCH, PEDALS, CONTROL STICK?

The probability of this event with all three different systems fails is 1:10000000000 => absolutely possible, almost likely!

The good news are: HUMS system is picking up all the missing information and the HUMS system is using its own sensors and pick-ups. The FMS/GPS will preserves short history data (integrated circuits) of airspeed, ground speed, heading, altitude..... This capability is needed for the dead recording function! There is still a possibility that the truth and nothing but the truth...

gulliBell

23rd Mar 2016, 02:56

Wasn't FDR validation testing one of the aspects picked up on by the post accident audit? The FDR had to be periodically tested to ensure that all parameters were being recorded, I don't think Bristow had been doing this. I'd be surprised if there had been any undue interference with the data before the FDR had been shipped to the UK; probably just lack of maintenance oversight that it wasn't working properly.

Please bare in mind that some operators have been flying S76 safely for 35 years without a single accident. Safe operation depends on the pilots flying them and the mechanics maintaining them. If there was an inherent flaw in the S76 flight control system design then loss of control accidents would be more prevalent than what history shows.

I'm sure they'll be able to unravel the circumstances of what happened to the Bristow accident despite not having a full set of FDR data. I still suspect there was an electrical gremlin that suckered the crew into thinking they had a flight control mechanical problem.

Copterline 103

23rd Mar 2016, 08:01

@gulliBell
The FDR had to be periodically tested to ensure that all parameters were being recorded

This periodical test is a mandatory test which must be done in every 12 months period. This annual test is not a test that the FDR is recording, this is the test what verifies that the recordings are correct and exactly following the position of e.g. flight controls. Before this test you have to follow (in ground and hydraulic ground power mule connected) precise instruction to move step by step the helicopter's flight controls. The aim of this test is to verify that the FDR recording is 100 % matching to the created series of the control movements. This annual test is normally made by using special software to print out the FDR recording data by the approved maintenance organization or by sending the FDR unit to the Penny & Gilles for the annual test. This Penny & Gils FDR is combined with CVR to be Penny & Gils FDR/CVR.

The functionality test is mandatory to perform before every flight. Penny & Giles FDR/CVR test is the item which should be a check list item. Before commencing a flight the commander has a responsibility to perform FDR/CVR test. This test will ensure that the FDR/CVR works perfectly and its network of sensors and pick-ups are connected to transfer data to the FDR/CVR unit.

The test is a simple push button test. If I right remember when the test is activated the Penny & Giles test panel shows “TEST” and if the test is not passed a “FAIL” caution will illuminated. If the FAIL caution is illuminated then the crew should follow company’s approved MEL procedures. This Penny & Giles FDR/CVR is a combined unit and in EASA world there is not much to do rather than to ground the helicopter until the defect is fixed. In EASA world the helicopter will come unairworthy if FDR/CVR is U/S. I’m not familiar FAA or NCAA ruling of this but don’t believe that under FAA or NCAA doesn’t allowed to operate S76 helicopter without FDR/CVR in commercial operation, commercial offshore operation (OGP).

The helicopter operator is required to have a CAMO. This organization is responsible for the helicopter’s airworthiness and that all the maintenance action will be order to do by a approved maintenance organization in timely manner. Each helicopter must have an approved maintenance program where e.g. FDR/CVR’s all maintenance intervals and maintenance action must be descript. The CAM is responsible to create work orders to cover all the necessary and all the mandatory maintenance action which must be performed within the issued due flight hours, calendar times and cycles (e.g. landings and engines) and all affecting SB's, ASB's and AD's must be taken account.

Every helicopter’s airworthiness has to be double check by Airworthiness Review Certificate (ARC). This review must be done annually by the accepted organization which is commonly the CAMO organization. The aim for this review process is to ensure that the maintenance program is covering all the required maintenance actions and tasks. In addition the review double check that all maintenance action has been (in the past) performed, performed in timely manner and all maintenance documents are objectively and carefully filled.

I can’t believe that Bristow Helicopter has skipped this FDR/CVR annual and a mandatory test. I can’t believe that the Bristow Helicopter operation (training & flight activity) culture could accept that some of the mandatory company test procedures are skipped e.g. FDR/CVR test.

The lost data will be picked up from the HUMS unit's memory disc and from GPS/FMS internal memory so "the truth is still out there".

@gulliBell
If there was an inherent flaw in the S76 flight control system design then loss of control accidents would be more prevalent than what history shows.
Let’s postpone this matter to the near future until we have e.g. data of these two accidents hydraulic fluid contamination or non-contamination. Anyway, you can prepare yourself be surprised...

gulliBell

23rd Mar 2016, 09:59

I've never done a pre-flight FDR/CVR test before, didn't even know it was something that needed to be tested. I just assumed FDR/CVR was one of those optional things that you didn't need in a helicopter < 5700kg MTOW.

I just checked the MMEL, sure enough, FDR is Cat A for some classes of operation....

Copterline 103

23rd Mar 2016, 10:58

@gulliBell
I've never done a pre-flight FDR/CVR test before, didn't even know it was something that needed to be tested. I just assumed FDR/CVR was one of those optional things that you didn't need in a helicopter < 5700kg MTOW.

I just checked the MMEL, sure enough, FDR is Cat A for some classes of operation....

Do you have or do you have had a S76 type rating? Are you familiar with Penny & Gils FDR/CVR?

My understanding is that EASA and FAA requires FDR/CVR to be installed all twin engine helicopters where the helicopter's type certificate has the approved passenger seats to be ten or more. This is a mandatory safety equipment in the helicopter industry.

The modern offshore helicopters are equipped with HOMP (Helicopter Operation Monitoring Program) or with FDM (Helicopter Flight Data Monitoring) systems. This is a requirement of the customer (OGP).

Sikorsky has not sold any S76 helicopters since the last 20 years without FDR/CVR. The most likely they want to know how it happened, when the event has occurred.

gulliBell

23rd Mar 2016, 11:19

Copterline 103

23rd Mar 2016, 12:16

We took 3 seats out of our helicopters and convinced the regulator that was enough reason to escape the 10 passenger seat rule...obviously makes life a lot easier for all sorts of reasons.

In 3,800 hours S76 offshore I never checked the FDR once, nobody ever did. We were never told we had to, or how to, or that an FDR was even fitted. I don't even recall a CVR being fitted in the 76 A or C, but I do know we had them in the C+ and C++ because there was a black box in the cockpit with an erase button and annoying green lights that blinked when you spoke.

Ups,
Very interesting! Didn’t you and your regulator ever realize that the ten or more seats rule is defined from the helicopter type certificate, not on the seats what you kicked out?

Yes, you are right that there are some black boxes in the helicopter and also could be a black box in the cockpit. Don’t press any button if you don’t know what the button is.

Did you had any conversion training, recurrent training, OPC’s, LC’, any annual recurrent system training for S76 series helicopter? Is it a long time since all this happen?

gulliBell

23rd Mar 2016, 15:13

When the oil company owns the whole show, including the helicopters, life becomes so much easier.

JimL

23rd Mar 2016, 15:42

In Europe, the requirement for a CVR/FDR is driven by a MCTOM of 3175kg, not seating capacity - unlike FARs.

This is from the ICAO Annex 6 Recommendation. In 2018 the discriminant will drop from 3 180kg to 2 250kg - for all new turbine type certificates.

Jim

Copterline 103

23rd Mar 2016, 22:18

@Sanus
Cop103 you mention many interesting things but surely even a first year metallurgist could tell the difference between a thread that has failed through looseness (chaffing and wear) and a thread that has suffered sudden shear overload? The latter would have rolled over thread crowns etc.

Sanus, my knowledge is not limited to my first year metallurgist. You should remember that the 60.000 non-public documents have included specialist metallurgist reports e.g. from MIT. I’m counting on these MIT's experts knowledge and the experts reports what I have seen.

Your opinion that the control tube and the control rod end has separated as “has failed through looseness (chaffing and wear)”. If this has been the case then the question mark will come over Bristow’s maintenance organization and the technicians. I can't believe that the Bristow’s technicians will bypass during PFC or Daily Check (whatever is the used name for daily inspection) were the S76’s “formula” is open. This is an area of technician interest to check the condition of each Servo Actuators, links, rods, tubes, locking pins, safety wires, visual locking markings, fluid levels, bearings play, leakages ect.

Every technicians of S76 type knows that the area under the “formula” is the most critical area for the safety. If the scenario is like you descript “has failed through looseness”. This development will take time to be separated. The time what is needed to make this looseness to be a separation is not a short time. During this long time this defected control tube and the control rod end should be passed quite many technician's eyes and hands. This doesn’t make sense for me and doesn’t make sense for Bristow’s maintenance organization.

The flight crew should have an indication (during hovering) that the basic, neutral position of control stick has removed and also the play on the rod assembly makes the most likely the helicopter to be unsteady because the flight controls rigging is changing all the time...

The FAA's certification requirement for the helicopter type certification insists that the all critical components or systems should ensure the continuity of safe flight. The all critical components of the all critical systems must be:

1. Redundant (dual systems, hydraulic systems, electrical systems, ect.)
2. Fail safe (single rods, links, tubes, ect.)

This Control rod tube and the control rod end belong to under of the requirement of FAIL SAFE. When the control tube and the control rod end have separated the mandatory requirement of fail safe component doesn’t exist. This is the helicopter type certification requirement. The S76 helicopter is certified under the FAA's Transportation Category. This certification could be an issue and the present finding could have an affect to the airworthiness?

We remember that the accident of 12th of August, 2015, where six people lost their lives.

ericferret

23rd Mar 2016, 22:42

What formula?
How is this "formula" defined?

gulliBell

24th Mar 2016, 02:10

I think these control system discussions are a diversion. Bristow maintenance would have inspected the flight control components of the whole fleet in infinite detail following the fatal accident. I'd be more interested in exploring what may have happened electrically that may have suckered the crew into thinking they had a mechanical problem.

And as for whether a CVR/FDR is fitted and required parameters are validly recording, as a pilot I don't care about this. If a component is due for testing it with be entered in the technical log, and a maintenance guy will attend to it. If it's due and the entry is open I don't accept the aircraft. If a pre-flight check of a component is required of the pilot it will be written in the body of the RFM, or in a supplement, and I will do it as written.

I have never had reason to check any FDR, pre-flight or otherwise. Is there something the Bristow pilots needed to do pre-flight in relation to the FDR?

tistisnot

24th Mar 2016, 05:29

I have always completed a daily inspection which included testing the CV/FDR .... press the tit and ensure the relevant lights extinguish, simple.

I know that maintenance performs an annual test for the authority to ensure the data from the FDR is correct, standard.

The longer term question for the authority, and in this particular instance for Bristow Nigeria maintenance and their safety culture, is how this was not done and why so many individual items failed to record. This is part of the safety system - for everyone, Zero.

Copterline 103

24th Mar 2016, 06:54

@ericferret
What formula?
How is this "formula" defined?

This "formula" is a S76 series helicopter's upper (deck) cowling. This term is used by the factory and e.g. Flight Safety, Florida. The profile of upper deck cowling separately looks likes a formula car profile.

John Eacott

24th Mar 2016, 07:02

This "formula" is a S76 series helicopter's upper (deck) cowling. This term is used by the factory and e.g. Flight Safety, Florida. The profile of upper deck cowling separately looks likes a formula car profile.
Never, ever heard it called that: it's been known as the 'race car' for as long as I've been S76 qualified. About 1980.

Copterline 103

24th Mar 2016, 08:48

@gulliBell
I'd be more interested in exploring what may have happened electrically that may have suckered the crew into thinking they had a mechanical problem.

I looks that your knowledge is limited. I have had a possibility to see behind the curtains (60.000 non-public documents). For me this is like a mathematical formula where the mathematical outcome is already known by me. Now I have to put the pieces together to verify what happen and to see what will come to happen.

Let’s keep your (gulliBell) lead also to be open but let’s keep also the focus on the airworthiness issues. The sentence what you wrote that “as a pilot I don't care about this” is like to a statement “It can’t happen to me”. Working in the aviation and working in the helicopter industry needs to have an attitude where everybody is focused to do the work carefully. The reality is that even you have made your duties well yesterday. It doesn't help, the sun is raising again in the morning and once again everyone have to do their duties 100 % focused to the safety, reliability and efficiency.

The helicopter industry’s 100 % safety will be achieved by global fleet grounding. The reality is that this world needs to have helicopters to be flying. By developing and improving the helicopters safety and reliability the helicopters could remain to be certified.

The helicopter operation should reach at least the level of accepted risk (vs. safety). In the helicopter industry we are dealing with the risk daily.

We have seen in the industry what happen to the fleet of EC225. Quite a number of accidents were taken place and too many innocent people have to lose their lives before the fleet was globally grounded. This global fleet grounding and re-certification process took more than a year. Now the EC225 are airworthy again and flying safely and with high reliability. This is the common industrial practices to ensure the crews and passengers safety.

“Out there” is still thousands S76 pilots and technicians who are working daily with the S76 series helicopters. They have very limited knowledge of the reality what stays behind the curtains. I understand that they have to right to know what a f… is going on out there….

My opinion of these two latest accidents: If the negligent are the flight crews or the Bristow’s technicians. Then we have had already seen a front page news with a colored picture to show how those who are responsible have already been hanged to the first suitable tree branch. This is the practice in the world where the money will be always number one and the safety number zero. This assertion seems to be behind the Bristow’s slogan “Target Zero” ?

industry insider

24th Mar 2016, 09:13

We have seen in the industry what happen to the fleet of EC225. Quite a number of accidents were taken place and too many innocent people have to lose their lives before the fleet was globally grounded. Rubbish Copterline. I am not aware of a fatal accident anywhere in the offshore industry in an EC225. The fleet was only grounded by statute in certain places.

According to you, every S-76 accident is caused by a servo problem. You are wrong and I am getting a bit fed up reading your posts which show little or no objectivity. You are looking for every accident to fit your pre-conceived theory.

Copterline 103

24th Mar 2016, 09:56

Rubbish Copterline. I am not aware of a fatal accident anywhere in the offshore industry in an EC225. The fleet was only grounded by statute in certain places.

According to you, every S-76 accident is caused by a servo problem. You are wrong and I am getting a bit fed up reading your posts which show little or no objectivity. You are looking for every accident to fit your pre-conceived theory.

@industry insider
The most likely you are the one who works behind the curtains. Please, read your hidden and non-public documents and think. If the airworthiness is ok there would be nothing to hide?

Regarding your statement of the EC225 (marketing name of different version of Puma's) "I am not aware of a fatal accident anywhere in the offshore industry in an EC225. The fleet was only grounded by statute in certain places."

This is very strange opinion. When the whole fleet of different version of Puma helicopters were globally grounded, there was a real reason for it! It was the main gearbox lubrication issue. You shoud read and study these accident reports and also the EC's statement how to fix the problem and what they did.

I have been waiting that you will show up behind the curtain. Are you ready for the truth? I'm ready.

I'm finishing to wrote a book which is named "The truth and nothing but the truth". In the book is "a fictive story" what f... is going behind the curtains.

squib66

24th Mar 2016, 11:23

"The truth and nothing but the truth": was that a deliberate choice to name your book after a Jerry Springer show?

gulliBell

24th Mar 2016, 11:27

@Copterline 103: I am a training Captain on the S76. Our clients are primarily offshore S76 operators who send their pilots to us to do initial and recurrent training on C++. I also do recurrent training for VVIP corporate clients as well. So I have a reasonable understanding of the aircraft and the common mistakes pilots make.

The VVIP pilots are usually at a good standard, both in technical knowledge and flight manoeuvre technique. The offshore guys much less so, particularly technical knowledge and CRM, although their hand flying is generally OK. Utter confusion usually reigns when we get to some particular malfunctions, including AFCS, use of the autopilot and flight director modes, and avionics/electrical malfunctions.

Time and time again I've seen pilots get themselves so utterly confused with a relatively minor malfunction that the safety of the aircraft is put in jeopardy. I see pilots attempt the same solution to a problem 5 or 6 times over before I tell them to think of something else. If a solution doesn't work first time (e.g. reset an AP), why would trying the same thing 5 or 6 times over yield a different result? This is what I'm seeing in the Bristow FDR data, AP2 reset attempted 7 times during the course of the flight. This is telling me they were short on other ideas. I see it all the time.

The flight control malfunctions are generally handled much better. With "whether to land immediately" decision making in response to a malfunction, a bad decision to keep flying is probably made 99 times to every un-neccessary decision to land/ditch immediately. So in this instance, if in hindsight the crew made a wrong decision to ditch, that would be out of character. Because, as I say, if there is a bad decision, it's usually to keep flying when they shouldn't.

With this experience in mind, and piecing together the little we know about what happened, I strongly suspect something electrical happened that suckered the crew into thinking they had a flight control malfunction that necessitated ditching. There is no electrical malfunction in the 76 that requires "land immediately", except for an electrical fire that can't be extinguished. I would be very surprised if the problem was hydraulic or flight control binding/jam/interference, but I shall keep an open mind until they work it out.

212man

24th Mar 2016, 12:02

Regarding your statement of the EC225 (marketing name of different version of Puma's) "I am not aware of a fatal accident anywhere in the offshore industry in an EC225. The fleet was only grounded by statute in certain places."

This is very strange opinion. When the whole fleet of different version of Puma helicopters were globally grounded, there was a real reason for it! It was the main gearbox lubrication issue. You shoud read and study these accident reports and also the EC's statement how to fix the problem and what they did

Yet again you show your ignorance (I'm being polite!) The majority of 225s were grounded by the operators/customers (O&G companies). Some authorities banned flights overwater but not overland. Some operators continued to fly without restrictions e.g. in SE Asia. All 725s remained in operations. There were no fatal 225 accidents.

I think you'll find that Industry Insider knows his facts - it's a pity you don't :ugh::ugh:

pilot and apprentice

24th Mar 2016, 12:31

I agree you are on the right track Gullibell. It is an unfortunate fact that flying in Nigeria, getting regular Trim lights and issues is just another day at the office. With experience it is just an annoyance. The daily CVR/FDR test is done but if one called it off every time a light stayed on one would be shown the door. Try a reset post-flight or MEL it...

I have also seen crews that look at the possibility of conducting even a VMC trip with degraded automation with extreme trepidation. This isn't entirely their fault. The sim sessions conducted by Bristow Nigeria are extremely limited and the time has to be carefully weighed. Understanding the automation first, then hands and feet skills if you can.

Copterline: You speak a lot about what could not possibly happen, what must be happening because it is in the European regs, etc. Clearly, you have not worked in the environment where these accidents happened. The recent rapid nationalization has happened to maintenance as well. Good intentions are great but it takes time and exposure for engineers, just like pilots, to get really good at the job. I absolutely do not believe anyone made a deliberate error, or cut a corner, but the system is desperate to move people up in the chain with a bare minimum of experience. I've been there (in Nigeria and an apprentice elsewhere) and I can't believe the pace of staff change that is happening.

Confirmation bias is what I think is happening. I understand you have an issue with the 76 but I have seen it put through a brutal torture test in another incident a few years ago and it stood up incredibly well. We rely on many systems to keep us alive on the job. The people are usually the weak link and will continue to be.

After all this, I'm wishing HC and Crab were back at it on here :-)

Copterline 103

24th Mar 2016, 12:37

@212man
I think you'll find that Industry Insider knows his facts - it's a pity you don't

These whom are working in behind of the curtains are to be paid that they will lead the attention to the area of their interest. They are not the first one whom are willing to have FDR data or HUMS data to be published. It is very relevant information to know how the helicopter's has behaved during the last half an hour. They are not the entity whom is willing to publish the status of hydraulic fluid contamination or non-contamination.

Let's keep all options open and let's hope that the truth will be released to the industry in timely manner. Hope that NAIB will release further information of 12th August, 2015 accident like FDR recording if still available and information of the fluid contamination or non-contamination of these both accident cases.

Copterline 103

24th Mar 2016, 12:47

@pilot and apprentice
I agree you are on the right track Gullibell. It is an unfortunate fact that flying in Nigeria, getting regular Trim lights and issues is just another day at the office. With experience it is just an annoyance. The daily CVR/FDR test is done but if one called it off every time a light stayed on one would be shown the door. Try a reset post-flight or MEL it...

Very hard to believe that the one of the biggest helicopter company, a listed company could be so low? I can't belive it. If this is the truth the the case is not any more a civil court case? Sorry, I don't believe this.

gulliBell

24th Mar 2016, 13:02

What does the condition of the hydraulic fluid have to do with the 12th August accident? The control rod came undone, doesn't matter how clean or dirty the hydraulic fluid was, or how full the hydraulic module reservoir was, once that control rod comes undone it's game over. As a matter of thoroughness I guess all the fluids would get tested as part of an accident investigation. In the S76 the hydraulic pressure filter is not a bypass type, so any dirt should remain on the upstream side of the filter until eventually the filter gets totally blocked with the accumulation of further dirt. Unless of course the source of the dirt is in the servo, which if it is making particles then you're potentially in a spot of bother. The hydraulic filter on the downstream side of the servo is a bypass type, but that is for a different reason (you don't want that filter blocking because the pressure across the servo will equalise causing the piston to lock).

HLCPTR

24th Mar 2016, 14:27

Unfortunately, all this talk of "behind the curtain" is starting to look too much like a conspiracy theory. It serves no purpose to speculate, especially when hints of hidden agendas are mentioned.

To each his own.

Copterline 103

24th Mar 2016, 21:30

@HLCPTR
Unfortunately, all this talk of "behind the curtain" is starting to look too much like a conspiracy theory. It serves no purpose to speculate, especially when hints of hidden agendas are mentioned.

In the court proceedings between the parties, it is possible “to get to see behind the curtains”. The procedure is defined in US law and the name of the procedure is a Discovery. This Discovery Order will be given by the Court.

Discovery, in the law of the United States and other countries, is a pre-trial procedure in a lawsuit in which each party, through the law of civil procedure, can obtain evidence from the other party or parties by means of discovery devices such as a request for answers to interrogatories, request for production of documents, request for admissions and depositions.

Under the law of the United States, civil discovery is wide-ranging and can involve any material which is "reasonably calculated to lead to admissible evidence." This is a much broader standard than relevance, because it contemplates the exploration of evidence which might be relevant, rather than evidence which is truly relevant.

In practice, this means that the both parties have to hand over to the opposite party all of its own internal and external documents, memos, e-mails, reports that directly or indirectly may be related to be a lead to the evidence or to be a evidence in this case. The Discovery material must be complete (without leaving anything out) for documentaries, under penalty of perjury.

I have had possibility to read the discovery material and to see behind the curtains.

This Discovery material are normally in aviation cases manufacture’s internal reports, internal emails, internal memos, internal notes, internal test reports, internal accident reports and findings, emails and the letters between manufacture – aviation authority, manufacture – national safety board or internal documents between manufacture and its subcontractors ect.

The Discovery process will give very good understanding of the counter party’s real knowledge or e.g. hidden non-public documents, if any.

I have had possibility to read 60.000 different documents and to create good understanding what is the public knowledge and "the internal knowledge with hidden issues”, if any.

This is not a conspiracy theory and there is no conspiracy. The truth maybe still out there but the all facts are already well known.

John Eacott

25th Mar 2016, 00:59

This is not a conspiracy theory and there is no conspiracy. The truth maybe still out there but the all facts are already well known.

Yet to most of us here, that is what you are persistently posting that you believe a conspiracy is preventing everyone but you seeing your truths.

Not only that, but you certainly appear not to be a helicopter professional, nor even a pilot or engineer. It matters not how many of the 60,000 documents you have read, it seems that you have a shallow understanding of offshore ops and an even shallower understanding of flying or maintaining the S76.

Copterline 103

25th Mar 2016, 15:39

Not only that, but you certainly appear not to be a helicopter professional, nor even a pilot or engineer. It matters not how many of the 60,000 documents you have read, it seems that you have a shallow understanding of offshore ops and an even shallower understanding of flying or maintaining the S76.

Maybe I'm slow and not as smart. Just a humble TRI/TRE deeply involved in the issue during the last couple decades and so far I have done quite well.

In professional Forum I appreciate to discuss in professional manner. My main concern is flight safety, noting more nothing less.

HLCPTR

25th Mar 2016, 16:18

Then may I respectfully suggest that if you have a point to make, that you make it clearly and specifically. Multiple rambling posts, hinting at unseen/hidden agendas and issues which only you understand add nothing to the discussion.

Copterline 103

25th Mar 2016, 16:45

@gulliBell
What does the condition of the hydraulic fluid have to do with the 12th August accident?.....The hydraulic filter on the downstream side of the servo is a bypass type, but that is for a different reason (you don't want that filter blocking because the pressure across the servo will equalise causing the piston to lock).

My focus is not like yours. The issue of the Servo Actuator's is not related to filters or filter’s bypass. The issue is the Servo Actuator design. When the Servo Actuator's and its spool valve's C3 return port or both of the ports are blocked. If this will happen then the Servo Actuator will be jammed or fully extended. This will cause that the helicopter will come immediately unflyable and no single caution is addressed to the crew. If the blockage is partial or temporary then the situation could be that the controllability has been lost temporarily.

Let's wait until that we have more precise information like FDR data of 12th August, 2015 accident or when we have information of the fluid contamination or non-contamination.

gulliBell

25th Mar 2016, 21:01

The servo design can't be expected to accommodate a manufacturing defect, like what happened in the Copterline accident. The pressure filter is there to stop particles from the hydraulic pump getting to the servo should the pump fail. Gross contamination of the servo due to the servo itself failing isn't a design point, in terms of fail-safe, past what the bypass spool is supposed to do. The only way to counter an un-commanded extension/retraction of a servo is to depressurization the system at the servo inlet, which is the purpose of the servo shutoff valve.

As far as I know, in the Copterline accident the crew didn't switch off the servo when its power piston went to full extension. I don't think they knew they were faced with a hydraulic problem. In any event, switching off the servo might not have saved them because both servos had a problem, and as we all know, you can't switch off both servo shutoff valves at the same time (which is a design point). Again, as far as I know, if the after start hydraulic system check had been done properly then the Copterline crew should have realized there was a problem with the servo. But that was a different accident. I doubt that anything relevant to that accident, in terms of flight control system problems, can be applied to either Bristow accident.

Copterline 103

25th Mar 2016, 22:49

@gulliBell
The pressure filter is there to stop particles from the hydraulic pump getting to the servo should the pump fail.

Let's be precise. Between the Servo Actuator pistons and the spool valve there is no any filter. All the particles and debris what are removing from the pistons or piston rings will have a direct routing to the C3 return ports. The design issue (the design point) is the spool valve's C3 return (fluid) ports and the Servo Actuator structure. If the return port blockage occurs the helicopter will lose its controllability immediately.

gulliBell, this is the first issue what I can fully agree with you. The only way to get the helicopter to be flyable again (if the helicopter will come immediately unflyable) is to switch or #1 hydraulic OFF. This will release (expected) affected #1 Servo channel off (depressurized). If switching off #1 doesn't help then the next step is select the #2 hydraulic OFF. This will release (expected) affected #2 Servo channel off (depressurized). The most likely the second attempt will release affected servo channel and the helicopter will be a steerable and a flyable helicopter again.

The major challenge is: due to the servo system design the helicopter caution system won't make any cautions to the crew. The crew can't identify what is the failure. There is no warning or any cautions. The RFM doesn't have any emergency procedures how the crew should proceed if this emergency scenario will happen.

I doubt that anything relevant to that accident, in terms of flight control system problems, can be applied to either Bristow accident.

For sure, its too early to me or you to make any conclusions what has happen or what hasn't happen (these two Bristow accidents).

It's nice to see that you have a good understanding of the hydraulics and the flight control systems. Sorry, I made earlier a wrong conclusion of your capability and your knowledge due to your FCR/CVR comment which was little bit confusing as your earlier posts #521, #523 and #529.

gulliBell

25th Mar 2016, 23:50

I tell all my trainees "not all malfunctions are in the emergency checklist". It is very important to have good systems knowledge to understand why the emergency checklist says what it says, because when following the checklist hasn't worked, or if the problem is not mentioned in the checklist, to have an idea what corrective action in response to a malfunction might be appropriate. So many times I see trainees following a checklist procedure that they have no idea what they are doing, or why, and that is a big problem because they might be on the wrong checklist procedure and not realize it, or they will have no idea whether what they are about to try is sensible in the circumstances, or what they should do if what they have tried doesn't work.

Sikorsky are not going to write in a checklist "if the helicopter goes wildly out of control immediately switch off a hydraulic system, and if that doesn't work, switch off the other one". This is what I would do if faced with this situation. I wouldn't even check if a servo light or master caution light or any other warning light is on, and I wouldn't even get out the checklist. Sometimes prioritization of common sense needs to over-ride strict compliance with procedure.

There have been times I see trainees become so confused when following a checklist procedure I end up taking it off them and say solve the problem without a checklist. The outcome is usually a better one compared with what they were doing before.

And as for my earlier comments about CVR/FDR, I have never seen anything in any regulator approved operator in-flight checklist about a pilot needing to do anything about these. Not in the S76, or any medium-twin Bell helicopter. I do know that passenger seats have been permanently removed from aircraft to bypass the CVR/FDR requirement, and I do know that HUMS has been removed from aircraft when it was not a contract requirement.

Reliance on automation in helicopter cockpits over the years seems to have reduced pilot capacity for doing the basic piloting stuff when something goes wrong.

industry insider

26th Mar 2016, 02:10

Sikorsky are not going to write in a checklist "if the helicopter goes wildly out of control immediately switch off a hydraulic system, and if that doesn't work, switch off the other one". This is what I would do if faced with this situation.

I had an excellent Training Captain during my conversion, in ground school, I was taught to turn off each hyd system in turn if I ever experienced any hint of control issues. I was also taught the importance of the after start / pre flight hyd check. But that was a long time ago.

gulliBell

26th Mar 2016, 04:35

90% of the recurrent trainees I see don't do the after start hydraulic check properly, which makes me wonder why they were never taught properly from the outset, or since.

Geoffersincornwall

26th Mar 2016, 08:30

A couple of points:-

1. Can you simulate this malfunction (servo block) in the simulator? If so is it included in the TR and practiced in the recurrent training?

2. In my AW139 I have about 300 possible malfunctions that the displays will bring to the attention of the pilots via the Crew Alerting System (CAS) or the PFD. To imagine that the pilot can work out what to do in every case courtesy of his (Ground School acquired) technical knowledge is, I think, wishful thinking. The situation means that they have little choice but to track down the relevant passage in the Quick Reference Handbook (QRH) and read it then do what it says. Often there will be a lack of explanation that helps the pilot to understand why he should take the action described in the QRH. One lives in hope that these knowledge gaps will be filled by the much anticipated FCOM. I hear that the FCOM for the S76D has been published - does this contain any revelations about hydraulic malfunctions?

G.

gulliBell

26th Mar 2016, 09:42

The malfunctions in the simulator are as per straight out of the RFM, and that doesn't include un-commanded extension/retraction of a servo piston. If there was demand from clients to practise this malfunction then a case could be made to the simulator manufacturer to update the software to do this (= expensive!). I don't know how close the motion simulation would be able to get, it would be a pretty wild ride I expect.

Copterline 103

26th Mar 2016, 09:43

@gulliBell
90% of the recurrent trainees I see don't do the after start hydraulic check properly, which makes me wonder why they were never taught properly from the outset, or since.

I fully agree with this but my experience tells me that the 99 % of the S76 pilots and instructors don't understand what they are checking. All our pilots have been type trained by a simulator company in Florida. Each crew member has had recurrent flight training in sim twice per year (6 months interval). This simulator training organization never pointed out how to do Stick Jump test properly (during the type rating course or during the 6 months recurrent flight training).

The Stick Jump Test is the hydraulic check of S76. The aim of the check is to verify that both hydraulic systems (HYD1 and HYD2) work well and at the same time as the HYD1 or HYD2 is OFF line that the Servo Actuators are checked by one servo channel one by one. This is commonly known, understood and performed.

My opinion is that these 99 % of the pilots and instructors are forgetting to do or they don't know how to do the stick jump part of the test. The stick jump test's idea is to verify that the power of the Hydraulic System 1 and 2 and the power the Servo Actuator's channel #1 and #2 are on an equal level. To make this verification during the check the pilot must keep the control stick moving at the same time when he or she switches over HYD #1 OFF to HYD #2 ON or reverse. If during this cross over (together with the moving flight controls) from #1 to #2 or from #2 to #1 the stick should not make a jump. If the jump occurs it is an indication that the powers between the hydraulic systems are different or if the hydraulic power is equal between systems HYD1 and HYD2 then this is an indication that there is a difference between one or more of the three Servo Actuator's channel #1 and #2.

The common mistake during the test is that the pilot will stop the control stick movement at time when the pilot makes the HYD1/2 cross over (switch off and switch on). When the stick doesn't be on move at time of switching over from HYD1 to HYD2, can't any stick jumps be detected.

The most likely the Stick Jump is caused by the increased Servo Actuator's internal leakage rate. This is the way find out a development that is a flight safety issue. This Stick Jump can't be identified in a case where the leakage rate has decreased parallel during the time on both channels #1 and #2. Even the power of the Servo Actuator power is poor (less that minimum acceptable) but if the both channel's leakage rates are on an equal level, no Stick Jumps exists. This is a scenario where you could have unairworthy Servo Actuator installed but you are not able to pick it up by the Stick Jump Test, even the test is performed properly and within timely manner.

I have seen some endurance and continuity test reports which are proving that this is a kind of development that doesn't have to be developed in hours; this could develop within seconds.

I hope that some of the pilots and instructors will take into account the above, in their daily duties. I would like to receive some comments from the S76 line pilots and the line instructors are these things mention above something new for them? Please show up to the Forum.

Copterline 103

26th Mar 2016, 10:54

@gulliBell
Sikorsky are not going to write in a checklist "if the helicopter goes wildly out of control immediately switch off a hydraulic system, and if that doesn't work, switch off the other one".

Now we are closing the topic. How does the S76 helicopter fly? Now I don't mean the situation when the helicopter becomes suddenly unflyable. There should not be any malfunction identified which is not covered by the abnormal or an emergency check list. This is a basic certification requirement.

@gulliBell
This is what I would do if faced with this situation. I wouldn't even check if a servo light or master caution light or any other warning light is on, and I wouldn't even get out the checklist. Sometimes prioritization of common sense needs to over-ride strict compliance with procedure.

My understanding is that the commercial and the modern helicopter operation are based of the law, rules and the good industrial practices. The offshore operation under IFR is a multi crew operation where the crew coordination and cooperation is the ground for the safe, reliable and efficient operation.

It is very difficult to understand the attitude that if something catastrophically happens? The sole crew member will start to solve the emergencies by his intuition without identification, verification before acting. How is the crew coordination taken care of in this kind of cockpit culture? How this kind of operation culture been descript on the Flight Operation Manuals and how has this kind of operation been taken care of by the recurrent flight training?

This is an issue which also belongs in the category; I don't believe that this kind of operation culture can exist in any offshore flight operation organization.

As an examiner I should fail you due to bad attitude, lack of CRM, lack of crew coordination and due to non-compliance of RFM's emergency check lists.

Copterline 103

26th Mar 2016, 11:15

@gulliBell
The malfunctions in the simulator are as per straight out of the RFM, and that doesn't include un-commanded extension/retraction of a servo piston. If there was demand from clients to practise this malfunction then a case could be made to the simulator manufacturer to update the software to do this (= expensive!). I don't know how close the motion simulation would be able to get, it would be a pretty wild ride I expect

My opinion is that these malfunctions should be included to the RFM and also should be trained during recurrent simulator training to the flight crews "SWITCH OFF HYD1" if it doesn't recover the controllability "TRY TO SWITCH OFF HYD2" and hope that the recovery could be achieved.

SIK has this software already in GenHel simulator so it should be very easy to be updated to the all S76 full motion simulators.

gulliBell

26th Mar 2016, 11:19

The thing is, as we saw in the Copterline accident, if the servo goes to full extension/retraction the ride will be so wild and disorientating for all concerned that normal CRM will probably be thrown out the window as well. If one of the pilots has the presence of mind to switch off a servo, and then the other one if that didn't work, might actually save the day for them. Attempting to run a challenge/response emergency checklist by the book, when one pilot head is probably crunched hard up against a windshield pillar, and the other pilot head probably stretched on its neck not far away from the same windshield pillar also, and their adrenaline level and heart rates are immediately shot through the roof, to expect a vanilla dose of by-the-book CRM in these circumstances is fanciful.

One of the 2 pilots needs to have the presence of mind to take decisive action. The action needs to be announced, if possible; the circumstances do not lend themselves to a timely discussion of the matter.

I consistently see problematic CRM in a normal environment when there are relatively minor malfunctions to contend with, let alone when the helicopter is playing rollercoaster and trying to throw you out the door. This is the reality I'm afraid. An action taken that is not by the book but which saves the aircraft is a better outcome than a crew following a checklist perfectly all the way to the scene of the accident.

Copterline 103

26th Mar 2016, 11:58

@gulliBell
An action taken that is not by the book but which saves the aircraft is a better outcome than a crew following a checklist perfectly all the way to the scene of the accident

I fully agree about this with you but if the crew has the knowledge that the Emergency Check list has an item if helicopter will suddenly become unflyable without any cautions and warnings. The crew should memorize by heart that "SWITCH OF HYD1" and is doesn't make recovery "TRY TO SWITCH OFF HYD2" in a situation where the helicopter caution system is not capable to announce any caution or warnings.

My point is that this should be in the RFM, Emergency check lists and have to be just one of the emergency events that will be trained regularly by the full motion sim recurrent session for all the S76 pilots.

Geoffersincornwall

26th Mar 2016, 13:37

I can just imagine the guys back at the Sikorsky factory trying to get their heads around this. The system was designed and built by the previous generation of engineer/designers so in theory the current generation bear no guilt - if there is guilt to be borne. But would they be wise to come forward and admit that the hydraulic system has a fundamental design flaw? Can you imagine the fall-out that would accompany such an admission?

Can I ask you (Copterline) what Sikorsky have replied to your assertions?

Aye
G.

Copterline 103

26th Mar 2016, 14:50

@Geoffersincornwall
I can just imagine the guys back at the Sikorsky factory trying to get their heads around this. The system was designed and built by the previous generation of engineer/designers so in theory the current generation bear no guilt - if there is guilt to be borne. But would they be wise to come forward and admit that the hydraulic system has a fundamental design flaw? Can you imagine the fall-out that would accompany such an admission?

Can I ask you (Copterline) what Sikorsky have replied to your assertions?

Aye
G.

My case is still pending. The counter party is nowadays Lockheed Martin.

Geoffersincornwall

26th Mar 2016, 16:08

Copterline - has any kind of SB been issued on the subject of correctly carrying out the stick-jump test?

Copterline 103

26th Mar 2016, 16:26

@Geoffersincornwall
Copterline - has any kind of SB been issued on the subject of correctly carrying out the stick-jump test?

No SB's or no RFM updates!

gulliBell

26th Mar 2016, 22:15

The hydraulic interlock and stick jump test is in the RFM, it's always been there.

John Eacott

26th Mar 2016, 23:01

Maybe I'm slow and not as smart. Just a humble TRI/TRE deeply involved in the issue during the last couple decades and so far I have done quite well.

In professional Forum I appreciate to discuss in professional manner. My main concern is flight safety, noting more nothing less.

My apologies, but your previous posts had given me that impression. I see from subsequent posts that you have some pilot's knowledge.

gullBell, you are quite right. The 'stick jump' check has been around since the A model, and is well explained in the Flight Safety training manual from the early 1980s.

JohnDixson

27th Mar 2016, 02:24

Goes back to the S-58.

Best,
John

pilonrock

27th Mar 2016, 04:41

Had aa channel or 2 drop out on a SPZ 7000 on a A model in IMC with 8 pax on board. On a few different occasions .It was a little wiggly and took some passing control back and fourth as the leans began to step in but it was not uncontrollable. Interestingly enough the A model didn't have an AP and we spent the better part of our days on the dials in IMC. Never had to land until we " practically" had to.

This automation business is great when it works, but there is still a requirement to fly the helicopter - it's what pilots do!!! It's important that any pilot who has such a big responsibility in a larger transport category helicopter has a great deal of hands on flying experience several 1000 hrs and has faced many non scripted emergencies, under different meteorological conditions and operating theatres . Then and only then should they be permitted by industry to fly the big stuff.

I guess at the end of the day the mystery will be solved. Still no new ASB's ADs or out from The authorities on this issue.... Hmmm.

I am thankful though that no one died! Certainly seen too much of that over several decades.

Stay safe over there!

[email protected]

27th Mar 2016, 13:38

Well nothing much seems to have happened on this thread in the week I have been away skiing apart from some ramblings about hyd failures that may or may not exist.

It is reminiscent of the Wessex and Sea King drill of 'If in doubt, primaries out' since switching hyd 2 off with a hyd 1 jack hardover could cause a rapid attitude change that might not be controllable.

However, what has been suggested so far has been at odds with the Nigeria 'ditching' since whatever the problem was, it didn't make the aircraft unflyable as they made a controlled water 'landing' rather than crashing into the sea.

industry insider

27th Mar 2016, 14:37

Not surprising Crab.

As I said many posts ago, this was a simple autopilot issue which was mis interpreted by the crew. The fact that Bristow has sent all of its BHNL S-76 crews to the simulator for "additional training" alludes to the fact that "additional training" should prevent a recurrence in BHNL's view.

[email protected]

27th Mar 2016, 17:13

Much closing of stable doors long after the horses have bolted - at least that particular accident is unlikely to happen again - we'll have to wait for the next 'unusual' scenario to test the quality of the training/captaincy I suppose.

Copterline 103

27th Mar 2016, 19:06

@industry insider
As I said many posts ago, this was a simple autopilot issue which was mis interpreted by the crew. The fact that Bristow has sent all of its BHNL S-76 crews to the simulator for "additional training" alludes to the fact that "additional training" should prevent a recurrence in BHNL's view.

Dear industry insider, it might be too early to give any statement like this "this was as simple autopilot issue which was misinterpreted by the crew". There is nothing what will support your theory, so far.

Instead, the opposite views, there are facts that support or consider them as potential events (NCAA's mandatory maintenance checks on due within 72 hours and Bristow's statement of additional simulator training).

The Nigerian Civil Aviation Authority (NCAA) has ordered all Airlines operating the SIKORSKY S76C series to carry out a safety inspection on this helicopter type with immediate effect.
As an interim safety measure, the under listed safety inspections affects all Sikorsky S76C series helicopters operating in Nigeria.
The action required are as follows:
1. Visual Inspection in accordance with relevant S76C AMM 20-32-00.
2. Detailed Inspection in accordance with relevant S76C AMM 66-00-00.
3. Detailed Inspection in accordance with relevant S76C AMM 66-10-00,66-20-00,66-30-00,66-40-00.

The NCAA's mandatory order to inspect all S76 series helicopter within 72 hours and every 300 hours will give a lead. The mandatory order's ATA numbers refers that the area of the accident investigators interest. Based on the ATA numbers the area of interest is the Flight Control System (flight controls, rods, tubes, mixing unit, servo actuators, links, caution switches and etc).

Bristow Legal Director Tolu Olubajo's statement:
Bristow Helicopters said it had sent all its pilots on the Sikorsky S-76 series on simulator training in order to keep them abreast of latest developments. Bristow Legal Director, Tolu Olubajo …on training, we have sent all pilots on Sikorsky on simulator training on current handling of the aircraft, we are conducting test like hydraulic test, review all maintenance programmes, inspection and maintenance checks of cockpit, life jackets and so on,” he said.

Bristow's statement supports the facts that the additional simulator flight training focus is the controllability issues and the hydraulic check (Stick Jump test).

These are the hard facts together with the published Preliminary report which also support the scenario that the loss of the controllability was the event why the helicopter was ditched.

I have received today from the local source an unofficial information that the both of (12th of August 2015 and the 3rd February, 2016) accidents helicopter's hydraulic fluid were contaminated. Let's wait until the official confirmation will be received.

cpt

27th Mar 2016, 21:22

.... in case of hydraulic fluid contamination, then, shouldn't it be likely to find a record of clogged filters, abnormal fluid color and perhaps of a fluid change in the recent flights maintenance book ? (I have already seen an S76 contaminated hydraulic fluid that was looking more like a genuine Irish Guiness )
In this situation also I don't doubt, a further investigation procedure is required.

[email protected]

27th Mar 2016, 21:28

Hmmm - inspecting the whole flight control system rather than one specific item sounds much more like clutching at straws trying to find a plausible excuse for the ditching rather than an exercise in checking a failed system (that has been proven to have failed) to ensure there isn't a fleet-wide problem.

Sending the crews for further training just looks like a*se-covering but is only to be expected so someone is seen to be doing something.

Copterline 103

27th Mar 2016, 22:12

Okey, Houston, we've had a problem here!

Please check my the latest post Bristow accidents. The latest post has been transffered to the "Bristow S76 Down in Lagos discussion #131".

Very relevant post for the both threads and for the flight safety!

industry insider

27th Mar 2016, 23:29

Dear Copterline

My information is from "behind the curtain".

Copterline 103

28th Mar 2016, 09:04

@industry insider
Dear Copterline
My information is from "behind the curtain".

Dear industry insider, your posts has already been made clear your position and your intentions for the safety matters.

@industry insider
Rubbish Copterline. I am not aware of a fatal accident anywhere in the offshore industry in an EC225. The fleet was only grounded by statute in certain places.

According to you, every S-76 accident is caused by a servo problem. You are wrong and I am getting a bit fed up reading your posts which show little or no objectivity. You are looking for every accident to fit your pre-conceived theory.

@industry insider
Not surprising Crab.
As I said many posts ago, this was a simple autopilot issue which was mis interpreted by the crew.

@industry insider
But not too hard to fly the EFIS AP out if you slow down to 120 knots, especially if you have selected the AP off so you know its coming.
I still see no real reason for a ditching here.

@industry insider
The AP / AFCS didn't "fail". It was a relatively small anomaly. The decision to ditch a serviceable helicopter is therefore very puzzling when it flies perfectly well AP out with a little extra concentration.

@industry insider
We all know the obvious way to isolate and diagnose an AP issue. But as Nescafe says (and obviously knows or has been briefed by BHNL) the issue appears the crew may not know the AP like you do and combined with the Harmattan causing poor visibility, it seems that they "talked" themselves into the need for a ditching.

Industry insider, could you make an answer to Geoffersincornwall "what guys back at the Sikorsky factory curtains are thinking?" We all would appreciate it very much if you would slightly to open the curtain for us?

The question is a quote below.

@Geoffersincornwall
I can just imagine the guys back at the Sikorsky factory trying to get their heads around this. The system was designed and built by the previous generation of engineer/designers so in theory the current generation bear no guilt - if there is guilt to be borne. But would they be wise to come forward and admit that the hydraulic system has a fundamental design flaw? Can you imagine the fall-out that would accompany such an admission?

industry insider

28th Mar 2016, 11:18

Copterline

You are obsessed with a single theory based on one accident and you have no apparent ability to be objective. Your mass quoting of previous posts does not alter facts. Helicopters do crash or ditch for multiple reasons and crashes may not conform to your somewhat single track theory.

The S-76 series has 6m + flight hours and almost 40 years of operations. It has been a reliable helicopter overall. It is gradually becoming commercially obsolete now, it happens with all aircraft.

You may notice, no one else is debating with you anymore. They have given up because you will only listen to yourself. So post away to your heart's desire. I have lost the will to engage with you any more.

Copterline 103

28th Mar 2016, 12:23

@industry insider
The S-76 series has 6m + flight hours and almost 40 years of operations. It has been a reliable helicopter overall. It is gradually becoming commercially obsolete now, it happens with all aircraft.

ASN Wikibase accident and serious occurrence data base #178588

28-JUL-1978
Sikorsky S-76A N763SA Sikorsky Aircraft 0 near West Palm Beach, FL
21-MAR-1980
Sikorsky S-76A PT-HKB VOTEC 14 off Macaé, RJ
03-SEP-1980
Sikorsky S-76A N766AL Air Logistics 0 near Patterson, LA
12-MAR-1981
Sikorsky S-76A G-BGXY Bristow Helicopters 4 South Kirkton, Westhill, Aberdeenshire
31-MAR-1981
Sikorsky S-76A N765AL Air Logistics 0 Conroe, TX
29-SEP-1981
Sikorsky S-76A PT-HKC VOTEC 0 Macaé, RJ
30-APR-1982
Sikorsky S-76A C-GIMF Okanagan Helicopters 13 Gulf of Thailand
14-SEP-1983
Sikorsky S-76A N521AC Amway Corp 0 Lake Michigan
07-NOV-1983
Sikorsky S-76A PT-HKD VOTEC 0 off Macaé, RJ
08-NOV-1983
Sikorsky S-76A TF-RAN Icelandic Coast Guard 4 Western Fjords
13-NOV-1983
Sikorsky S-76A N4252S Houston Helicopters off Singapore
05-MAR-1984
Sikorsky S-76A N15479 private 0 Spartanburg, SC
01-MAY-1984
Sikorsky S-76A N763AL Air Logistics 0 High Island BLK595, TX
11-AUG-1984
Sikorsky S-76A N63WW Capital Equipment Associates 1 Fort Dix, NJ
22-SEP-1984
Sikorsky S-76A N79K private 0 near Unionville, PA
01-NOV-1984
Sikorsky S-76A N27422 Petroleum Helicopters (PHI) 5 off Hainan Island
19-FEB-1985
Sikorsky S-76A N31223 Petroleum Helicopters (PHI) 0 Houma, LA
11-JUN-1985
Sikorsky S-76A N176FJ Raco Helicopters 1 Belmar, NJ
28-JUN-1985
Sikorsky S-76A N5054Y Air Logistics 0 Eugene Island
05-JAN-1986
Sikorsky S-76A N7612L Air Logistics 3 near Houma, LA
06-JUN-1986
Sikorsky S-76B N5AZ United Technologies 4 Sutton, MA
04-FEB-1987
Sikorsky S-76A N767AL Air Logistics 2 Angleton, TX
30-MAY-1987
Sikorsky S-76 (AUH-76) 208 Philippine Air Force 4 Manila Bay
23-JUN-1988
Sikorsky S-76A N54C 0 Moundsville, WV
07-AUG-1988
Sikorsky S-76 N69WW private 0 Teterboro, NJ
22-FEB-1989
Sikorsky S-76A N767SA 0 Washington, PA
01-DEC-1989
Sikorsky S-76 (AUH-76) 209 Philippine Air Force 0 Sangley Point AB, Cavite City
12-MAY-1990
Sikorsky S-76 (AUH-76) 203 Philippine Air Force 9 Zamboanga
01-AUG-1990
Sikorsky S-76A+ JA9943 Aero Asahi 2 Hakone
22-AUG-1990
Sikorsky S-76 (AUH-76) 204 Philippine Air Force 1
17-JUN-1991
Sikorsky S-76A N5418N Petroleum Helicopters (PHI) 0 Gulf of Mexico
18-APR-1992
Sikorsky S-76A+ G-BOND Bond Helicopters 0+1 North Sea
07-AUG-1992
Sikorsky S-76A N50KY Kentucky State Government 0 Graefenburg, KY
06-FEB-1993
Sikorsky S-76A+ I-EAIR Eliair 4 Venezia-Tessera (VCE)
14-JUN-1993
Sikorsky S-76B HL9245 Sunkyung Engineering 7 near Seoul
23-APR-1994
Sikorsky S-76A PK-PUD Pelita Air Service 0 Udang Field, off Matak Island, Riau
08-NOV-1994
Sikorsky S-76A N2620 Mobil Administrative Services (MASCI) 1 off Cameron, LA
24-JUL-1995
Sikorsky S-76A VR-BQD private 0 Aspropirgos
09-APR-1996
Sikorsky S-76A B-7302 Zhuhai Helicopter 2 Dawanshan Island
12-DEC-1996
Sikorsky S-76B G-HAUG Norbrook Industries 3 2 mls SE of Omeath, Co. Louth
03-APR-1997
Sikorsky S-76B-7 2310 Royal Thai Navy 0 Bangkok NAS
22-SEP-1997
Sikorsky S-76A+ N517AL Air Logistics 0 Patterson, LA
03-OCT-1997
Sikorsky S-76A B-7301 Zhuhai Helicopter 7 off Wenzhou
20-DEC-1997
Sikorsky S-76B PH-KHB KLM/Era Helicopters 1 North Sea
- -1997
Sikorsky S-76B HL9249 Dong Ah Construction
20-FEB-1998
Sikorsky S-76C JA6733/MH733 Japan Coast Guard 3 37 km off Cape Esan, Kameda
18-MAR-1998
Sikorsky S-76A B-7306 Zhuhai Helicopter 2 near Zhuhai
28-MAR-1998
Sikorsky S-76A C-GMQE 0 Victoria, BC
24-JUN-1998
Sikorsky S-76A+ ZS-RIJ Court Helicopters 0 off Luanda
04-SEP-1998
Sikorsky S-76B I-LXCA Luxottica spa 0 near Padova
03-APR-1999
Sikorsky S-76A SE-JES Norrlandsflyg 0 25 km NE of Torneträsk
14-JUN-1999
Sikorsky S-76A N2743E Petroleum Helicopters (PHI) 4 Jackson, KY
08-MAR-2000
Sikorsky S-76A PK-PUK Pelita Air Service 2 South China Sea
02-AUG-2000
Sikorsky S-76A PT-HRD Líder Táxi Aéreo 5 Penha, SC
20-MAR-2001
Sikorsky S-76A N376AL Air Logistics 0+1 Gulf of Mexico
19-MAY-2001
Sikorsky S-76A 758 Philippine Air Force 7 Sitio Manguba, 60 km from Puerto Princesa
05-JUL-2001
Sikorsky S-76B HL9240 Dae-Woo Shipbuilding Co 8 near P'ohang
16-JUL-2002
Sikorsky S-76A+ G-BJVX Bristow Helicopters 11 28 mi NE of Cromer, Norfolk
22-NOV-2002
Sikorsky S-76A PT-HUI Aeróleo Táxi Aéreo 0 Macaé, RJ
30-JAN-2003
Sikorsky S-76B-7 2309 Royal Thai Navy 1 Ban Mai, Muang, Chantaburi
14-MAR-2003
Sikorsky S-76A+ C-FTGD Canadian Helicopters 0 Baku Airport
05-JUL-2003
Sikorsky S-76A PT-YVM BHS Táxi Aéreo 5 off Campos dos Goytacazes, RJ
22-AUG-2003
Sikorsky S-76A+ PT-YAU Aeróleo Táxi Aéreo 0 Macaé Airport, RJ
23-MAR-2004
Sikorsky S-76A++ N579EH Era Aviation 10 70nm SW, Galveston, TX, Gulf of Mexico (GOM)
20-APR-2004
Sikorsky S-76A PT-YBG Líder Táxi Aéreo 0 Macaé, RJ
22-JUL-2004
Sikorsky S-76A PP-MYM BHS Táxi Aéreo 6 160 km NE off Rio de Janeiro, RJ
18-SEP-2004
Sikorsky S-76C SE-JUJ Norrlandsflyg 0 E of Skräckskär
10-JAN-2005
Sikorsky S-76C+ JA6903/MH903 Japan Coast Guard 0 52 km WSW off Niigata (KIJ)
12-JAN-2005
Sikorsky S-76A PP-MCS BHS Táxi Aéreo 0 Macaé Airport, RJ
17-JUN-2005
Sikorsky S-76C+ N317MY Corporate Aviation Services 0 New York, NY
10-AUG-2005
Sikorsky S-76C+ OH-HCI Copterline 14 Baltic Sea, off Tallinn
06-SEP-2005
Sikorsky S-76A+ N90421 Houston Helicopters (HHI) 0 Gulf of Mexico
22-OCT-2006
Sikorsky S-76A++ N22342 Petroleum Helicopters Inc (PHI) 0 Eugene Island (EI) Block 259, Gulf of Mexico
- -2006
Sikorsky S-76A PT-HRF Líder Táxi Aéreo 0
-JUL-2007
Sikorsky S-76A++ B-73.. Zhuhai Helicopter/COPC 0 Bohai Bay
08-FEB-2008
Sikorsky S-76A C-GIMR Canadian Helicopters 0 Temagami, ON
29-MAY-2008
Sikorsky S-76A N176SH EMS Helicopters, opf. Aero Med 0 Grand Rapids, MI
18-SEP-2008
Sikorsky S-76B N399BH private 0 Bettystown, Meath County
04-JAN-2009
Sikorsky S-76C++ N748P Petroleum Helicopters (PHI) 8 near Houma, Terrebonne Parish, LA
11-MAR-2011
Sikorsky S-76C JA6905/MH905 Japan Coast Guard 0 Sendai Airport (RJSS)
11-JUL-2011
Sikorsky S-76C++ F-HJCS Héli-Union 3 Andaman Sea, off Myanmar coast
17-APR-2012
Sikorsky S-76B N56RD RDC Marine Inc 0 near Vermilion VR376A, Gulf of Mexico
13-AUG-2012
Sikorsky S-76A C-GHJT Helijet International 0 Langara Island, BC
26-SEP-2012
Sikorsky S-76C G-CGOU Bristow Helicopters 0 19 miles ENE of Humberside Airport, Kirmington, Lincolnshire
15-MAR-2013
Sikorsky S-76A++ N574EH Era Helicopters LLC 3 Grand Lake, LA
27-APR-2013
Sikorsky S-76B N305SJ Dominican Watchman National 0 Constanza
31-MAY-2013
Sikorsky S-76A C-GIMY Ornge Global Air Inc. 4 Moosonee, ON
16-NOV-2013
Sikorsky S-76C++ HL9294 LG Electronics 2 Gangnam, Seoul
05-DEC-2013
Sikorsky S-76B N707MY MYU Helicopters 0 Port Fourchon (LS99), LA
12-DEC-2013
Sikorsky S-76C 9M-STE MHS Aviation 0 South China Sea, 159 km off Bintulu, Sarawak
21-MAR-2015
Sikorsky S-76C+ PK-FUP PT Hevilift Aviation Indonesia 0 Kutai Lama, Anggana, East Kalimantan
12-AUG-2015
Sikorsky S-76C+ 5N-BGD Bristow Helicopters (Nigeria) 6 off Oworonshoki, Lagos Lagoon
03-FEB-2016
Sikorsky S-76C++ 5N-BQJ Bristow Helicopters (Nigeria) 0 75nm off Lagos

@Geoffersincornwall
I can just imagine the guys back at the Sikorsky factory trying to get their heads around this. The system was designed and built by the previous generation of engineer/designers so in theory the current generation bear no guilt - if there is guilt to be borne. But would they be wise to come forward and admit that the hydraulic system has a fundamental design flaw? Can you imagine the fall-out that would accompany such an admission?
Industry insider don't forget to make an answer for @Geoffersincornwall!

terminus mos

28th Mar 2016, 14:45

Are you suggesting, Copterline, that all of these accidents fit your pattern and theory? I am not sure you would be correct, if so.

I think it's you who should reply to Geoffers not II as its you who is making accusations against an OEM. What would you do?

HLCPTR

28th Mar 2016, 14:52

http://jeffbaij.com/blog/images/deadhorse.gif (http://www.bing.com/images/search?q=beating+a+dead+horse+gif&view=detailv2&&id=F38EB73C5D80D72CA668194541DA3F9364806CDB&selectedIndex=8&ccid=DQSvDpAX&simid=608055846928056959&thid=OIP.M0d04af0e9017b2174cfa2815c72c6380H0)

Copterline 103

28th Mar 2016, 15:15

@terminus mos
Are you suggesting, Copterline, that all of these accidents fit your pattern and theory? I am not sure you would be correct, if so

No, no but if you visit on ASN Wikibase occurrence / S-76 site you will find out that there is too many cases where the loss of the controllability is an issue. Check one by one these 93 accidents or occurrences you will have a picture.

Copterline 103

28th Mar 2016, 15:23

@HLCPTR your quote #581

I may be slow but if I read your symbols correctly?

do you mean: Do not beat it anymore, it is already dead?

Democritus

28th Mar 2016, 16:03

No, no but if you visit on ASN Wikibase occurrence / S-76 site you will find out that there is too many cases where the loss of the controllability is an issue. Check one by one these 93 accidents or occurrences you will have a picture.

So you quote a Wiki page - to which anyone can edit or post - as an authoritative reference? For a start they have the location of the 12 Mar 1981 tragic accident to a Bristow S-76 incorrect. As I was flying the same type from Aberdeen at the time I know it occurred near Peterhead and many miles away from the quoted Westhill. So what else do they have wrong.

Wiki also don't have my 1985 accident listed (a mechanical issue in another type). Wiki is hardly something you can rely upon to support your arguments. As HLCPTR indicates, you are 'flogging a dead horse' with your repetitive posts.

Keke Napep

28th Mar 2016, 16:34

I started this thread just as information about an accident to a Bristow S76 in Nigeria, but it has been hijacked by all sorts of people, but of late mostly by Copterline to keep flogging his dead horse about every accident or incident on the S76 having a root cause in the hydraulic system. Maybe my S76 tyre puncture when taxiing in Port Harcourt in 2006 was due to hydraulic fluid contamination? I don't know because I don't have access to 60.000 non-public documents :ugh:
Might I suggest that if this hydraulic horse is going to be flogged to death, Copterline starts a new thread of his own where those with an interest can avidly keep checking for the latest hydraulically inspired events while the rest of us wait to see if there's further concrete news about the S76 ditching.

Copterline 103

28th Mar 2016, 19:23

@keke napep
Maybe my S76 tyre puncture when taxiing in Port Harcourt in 2006 was due to hydraulic fluid contamination?

keke, there are already too many people who have lost their lives and too many families without their father or without their brother or sister. I wish that everybody would appreciate the flight safety. There are too many pilots who have to press ENG START BUTTON of S76 helicopters in daily bases. The safety and the real issues whatever these are have to be openly analyzed. My experience is that there are interest parties, who don’t care if someone died, but I care and I will make my best to make this helicopter industry safer for the crew members and passengers.

I can guarantee you that if there wouldn't be a real issue behind this I wouldn't care at all about these accidents. I wouldn’t care if someone innocent loses his or her life tomorrow. But I care and I have seen too much.

I have seen a tragedy where 14 people lost their lives, I have listened to more than 50 times CVR recordings to help the accident investigators to have an understanding what the f…. is ongoing when to pilots are fighting last half a minute of their lives. They made everything to safe their lives. After this experience I assume that every human will make all necessary actions that this will not happen again.

I hope that some crew could save their own lives and their colleagues lives by making the Stick Jump test properly and in a case of in-flight if all actions to analyze, verified and the helicopter is still unflyable. At least the crew should try to switch OFF HYD1 and if that doesn't help switch OFF HYD2. Referring to gulliBell #549

@gulliBell
The only way to counter an un-commanded extension/retraction of a servo is to depressurization the system at the servo inlet, which is the purpose of the servo shutoff valve.
As far as I know, in the Copterline accident the crew didn't switch off the servo when its power piston went to full extension. I don't think they knew they were faced with a hydraulic problem.

The flight safety is an issue which no one should take arrogantly, so I think your comment “the tire puncture when taxiing” and the reference to “the hydraulic fluid contamination” was very inappropriate and unprofessional.
My intention is not to hijack Your thread and I won’t do it. This thread has had 16.456 visitors during the last seven (7) days and the thread Bristow Down in Lagos has had 760 visitors during the last 24 hours. Let’s work together for the safety.

Keke Napep

28th Mar 2016, 20:06

Copterline,

You claim to be an S76 TRE/IRE and you talk about pressing an S76 start button? :confused:.

Well I've also got more than a few thousand hours on the type and am also a TRE/IRE on it. I lost a good friend, Mark Wake who was one of 11 killed when G-BJVX crashed into the North Sea in July 2002, and another 2 good friends when5N-BGD crashed last August.

Flight safety is not an attitude I take arrogantly, but I'm also not so arrogant as to think that ramming my own personal theories down everyone throat is a way of enhancing it. Sometimes bringing a little humour into a situation (even a tragic one) makes people remember things far better than listening to someone who constantly wants to be so arrogant as to assume they're the only one who can possibly know the answer and harps on about conspiracy theories behind closed curtains as a way to try and show he knows more than anyone else. If you have proof of something, man up and show us, otherwise your opinion is worth no more than any other person's.

Copterline 103

28th Mar 2016, 20:51

@keke Napep
You claim to be an S76 TRE/IRE and you talk about pressing an S76 start button? .

keke, I'm the lucky one since the last flight with S76C+ ten years ago. Since till now an TRI/TRE/IRI/IRE SP/MP for AW139.

Still memorizing that S76C+ start up sequence will be started by pressing start button which is located in the #1 and #2 Power lever and then the start up process is fully automatic. Correct if my memory is not good enough?

Keke Napep

28th Mar 2016, 21:56

Ah well, maybe you really have flown the S76 then, but flashing round lots of supposed qualifications really isn't a good way to try and make a point on this forum, unless you really are someone like Nick Lappos and he doesn't constantly push his qualifications down everyone's throat. Constant talk of 60.000 secret documents, helping numerous AIBs, IRI etc doesn't impress people who just get on, carry out daily or every day checks before flight as laid down either in the RFM or their company check lists. I'm sure you know that the only part of the RFM which is legally binding is the limitations section. However, in case of litigation, it would be a foolish company which did not incorporate all the elements of the normal and emergency checks from the RFM into their own checklists.
When I worked for Bristow we carried out the hydraulic checks as laid down in the RFM as part of each start up and carried out the FDR and autopilot checks daily or A/R (before each flight for IMC flight). Every pilot carried out annual simulator training (as required by the NCAA) of 12 hours (14 hours for those pilots carrying out command assessment for upgrade). In addition, while I was still working for them and we were using the FSI simulator in West Palm Beach we had a session on the GFS, covering one or two of the systems in more detail. In addition an Elite Simulators FNPT (based on an IFR AS355F1 with a simple EFIS) was purchased some years ago and eventually installed in a purpose-built facility in Port Harcourt so that pilots could receive additional instrument procedure training and MCC and Command training. Of course, Bristow do not have a GFS in their simulator facility in Aberdeen, but all pilots are required to do external online S76 refresher training every year.

Nescafe

28th Mar 2016, 22:02

but flashing round lots of supposed qualifications really isn't a good way to try and make a point on this forum

You mean, like you just did?

Well I've also got more than a few thousand hours on the type and am also a TRE/IRE on it.

Copterline 103

28th Mar 2016, 22:36

@keke napep
keke, this all looks good and it just like it should be (the flight crew training).

I'm disapointed that I couldn't give my knowledge early enough to Jay and his copilot. It would be a different story if they could make the recovery in the situation where they suddenly vent. It was cavok, 1000 ft. and 120 KTS.

I'm sure that Jay and his copilot tried to make everything to understand what is going on. I have been told that Jay was very capable on his duties.

Copterline 103

3rd Apr 2016, 20:37

@megan
Yes they can, because I've had it. Trouble is, I can't recall the root cause (we're talking 20 or more years ago), but the regulator was wondering if the aircraft should be certified IFR capable with such a single point failure. Nothing eventuated. Contact with Australian ATSB or the CASA Moorabbin office should elicit a copy of the incident report.
I did that already 2008. I got the incident report and other related material from Australian ATSB.

Megan, Is this the case you mentioned? You are right, there is a single point failure which could lead to the loss of controllability of helicopter. This Australia case was a lucky one due to stuck controls in the ground.

As you have seen the incident report which proves that there was none caution or warnings during this blockage. This single point defect or failure is well known and for sure still makes headaches to the factory and the authorities.....has this ever been acceptable.....?

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations), PART 39-105
Civil Aviation Safety Authority
Scheduled of Airworthiness Directives
Sikorsky S76 Series Helicopters
AD/S-76/22 Main Rotor Control Servo Actuators-Inspection 6/82 for Balance Tube Passage
Applicability: All models.
Document: Sikorsky Alert SB 76-67-14A. NOTE: Helicopter previously inspected to SB ASB 76-67-4 are to be re-inspected
Compliance: Within 30 hours time in service after 28 April 1982
Background: Restricted flight control motion was found to be due to the omission of a passage in the servo oil return system.

cpt

3rd Apr 2016, 22:04

Hi Copterline,

But in this Australian case, it was more likely a case of a mistake in the manufacturing process or a poorly overhauled servo....I suppose this fault has been revealed at the flight control check after a servo change ? it would rather highlight a quality control flaw, more than a design misconception.

Copterline 103

4th Apr 2016, 07:53

@cpt
Hi Copterline,
But in this Australian case, it was more likely a case of a mistake in the manufacturing process or a poorly overhauled servo....I suppose this fault has been revealed at the flight control check after a servo change ? it would rather highlight a quality control flaw, more than a design misconception.

cpt: The Australian case was an operator reported restriccted flight control motion on the ground. Troubleshooting determined the cause to restrected movement in the retract mode of one main rotor servo actuator stage. The cause of malfunction has been confirmed to be the omission of a passage connecting a chamber to system return. The servo had been reported to have been previously checked per the basic Alert Service Bulletin No. 76-67-14 (Sikorsky Message CST-SPT-81-0587, dated August 26,1981).

After this Australian AD an revised ASB 76-67-14B was issued by the manufacture.

In the Baltic Sea accident the findings were:
a) the plasma material was wrong
b) during Servo Actuator's overhaul process a non FAA approved maintenance instructions and procedure were used
c) the maximum certified thickness of the plasma coating was 4 microns but the actual plasma coating was 1,2 mm (1200 microns) which was 300 time more than the certified and accepted maximum

Despite the fact what is the reason why the C3 port or ports are blocked it not the biggest problem. The main problem is that a single defect in Servo Actuator could lead in loss of the helicopter controllability.
This is a helicopter type certification issue.