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-   -   Bristow S76 Ditched in Nigeria today Feb 3 2016 (https://www.pprune.org/rotorheads/574171-bristow-s76-ditched-nigeria-today-feb-3-2016-a.html)

fadecdegraded 9th Feb 2016 07:04

Well doesn't that make perfect sense, Im thinking she may have read the flight manual as well.

Same again 9th Feb 2016 09:12


Well doesn't that make perfect sense, Im thinking she may have read the flight manual as well.
An African female who can actually read might come as a surprise to some of the mysogonistic dinosaurs on this forum.

gulliBell 9th Feb 2016 12:11

Remember in the S76 you don't have a 30 minute MGB run dry capability. If you have confirmed loss of MGB PRESS you need to get low and find a place to land as soon as possible. If abnormal noise and/or vibration you need to land immediately, the gear box might only last a minute or two. If you see the TQ rising to maintain NR (even near flat pitch) you might only have less than a minute to get it down. Once the engines are maxed out the NR will start decreasing rapidly, you now only have a few seconds to land it. Do not autorotate at any stage of this malfunction, you must keep power going into the MGB to keep it turning.

Obviously I'm not speculating what might have happened in the Bristow instance.

TIMTS 9th Feb 2016 13:31

Latest rumor is that the crew called in with an "autopilot deviation"...

MamaPut 9th Feb 2016 13:35

Nope, not an MGB problem, not an autopilot deviation. Keep speculating, but it won't make a single difference to what actually happened :ugh:

gulliBell 9th Feb 2016 20:19

The only malfunctions that I can think of that would put an S76 in the water are MGB/TGB/IGB with noise/vibration, TR driveshaft failure, un-contained engine/electrical fire, fuel contamination/exhaustion, hydraulic with binding, double engine failure. There are a couple of others that might sucker a crew into needlessly putting it into the water.

The only one that makes sense to me in this instance is a fuel problem. Do they refuel on the platform? Just speculating.

terminus mos 9th Feb 2016 20:54

Or a perceived problem with the controls and the memory of August 12th while talking with base and getting advice?

gulliBell 9th Feb 2016 21:56

As far as I know, August 12th the crew had no prior indication, and once the control tube came undone there was nothing they could do to alter the outcome?

oleary 10th Feb 2016 01:15

Run dry
 

Remember in the S76 you don't have a 30 minute MGB run dry capability.
Yup, I totally agree.

In any case, anyone who thinks you can "run dry" a helicopter gearbox for any significant length of time is an idiot - regardless of what the manufacturer says.

On the 61 we had "emergency lube" but that was NOT run dry, it just lubed the inputs and bought you some time.

P&W experimented with a "paraffin lube" thing for the combining gearbox on the Twinpac in F/W but again, that was not run dry is was more like the 61 emerg lube system.

Finally, I am not speculating on what happened in this incident either. I will say there were no serious injuries so good on Captain Jayeola :D and her crew.

Geoffersincornwall 10th Feb 2016 07:08

O'Leary
 
You are so out of touch - I suggest you do some research on line and find the information about the run dry tests on the AW139 gearbox.

G. :ok:

gulliBell 10th Feb 2016 07:55

Point taken above about reading the RFM, but comprehension of what is written in the RFM can't be assumed (which is a general comment based on my observations as a teacher on S76). I have seen time and time again, even in crews with thousands of hours experience, not even being on the right checklist for a particular malfunction. There is no point running the wrong checklist perfectly because it probably won't solve the problem. Often it pays to stop reading and just think about the problem, because applying pilot common sense to a problem yields a more sensible outcome than being rail-roaded down the perfectly read wrong checklist.

Again, this comment is made completely not in relation to the specifics of this Bristow ditching.

Mars 10th Feb 2016 07:56

We have probably done this to death but any discussion about the ability for a gearbox to 'run dry' is nearly always a conditional statement. For example, Giuseppe Gasparini, head of transmission systems design and development at AgustaWestland makes this observation:


I prefer to say “Loss of Lubrication,” or LoL, and not “run dry” or “run without oil”; we are demonstrating the capability of the gearbox to operate and transmit torque after the loss of most of its original lubricant when the oil is suddenly lost, but some residual lubricant is still inside the gearbox. This means the MGB can continue to run for 30 minutes without loss of drive or any other catastrophic failure after the pilot notes a major lubrication system failure, normally identified as a low pressure warning, and immediately reduces power to the minimum required to maintain forward flight and lands as soon as possible.
Notwithstanding this, there have been real advances in the material used, and the finishing, for contacting surfaces within the gearbox.

(As with previous posters, this is not a comment on the S76 accident.)

Mars

Phone Wind 10th Feb 2016 08:31

As it seems unlikely that a MGB problem caused the ditching of this aircraft, why don't some of the people who are posting on here start a separate thread?

gulliBell 10th Feb 2016 09:48

A gearbox malfunction fits the profile of the little we know about what happened, more so than any of the other malfunctions I mentioned at #86. Those other malfunctions more than likely would put you in the water quicker than, from what we know, the time they had to fly around before making the decision to land on the water.

If it turns out to be something other than anything mentioned at #86 might make for some interesting reading. The S76 is a very well known quantity, but it is possible that something surprising might have happened. I'm sure they'll work it all out in quick time and thus end our mindless further speculation.

twisted wrench 10th Feb 2016 09:51

Goggle this article is interesting reading:


Nigeria: NCAA Expresses Worry Over Incessant Bristow Helicopter Accidents




I see the stock price dropped by almost $4 yesterday to new all time low, result of this incident or the last quarter results ( maybe both) ?

lowfat 10th Feb 2016 10:43

I would say due to the performance results... An incident in Nigeria which has hardly made the news in america/europe (if it all) will have no bearing on the share price.

Most investors wont know where or what Nigeria is I'm afraid.....

j.callagan 10th Feb 2016 11:13

"The only thing that matters is that GOD made the controlled landing happen. Whether he intervened during the flight planning process by interfering with HUMP .. Or during the actual flight... It was Devine intervention." pilonrock



I really want to see the passengers faces when they realize that pilots entrust and handover the SOPs, Flight Planning, OMs and Limitations to "GOD" and the "Devine intervention" :yuk:

gulliBell 10th Feb 2016 11:14

Look on the bright side, the tanking share price makes the dividend yield look pretty good :O

Phone Wind 10th Feb 2016 13:07

I've not read such a load of garbage in a long time as the article in 'This Day' which comes of googling the words suggested by twisted wrench, but then Nigerian newspapers, as has already been mentioned several times on this thread, are renowned as being high in sensationalism and low in fact content. It's quite obvious that the source in NCAA is unhappy that Bristow doesn't pay bribes to officials, unlike some of the local operators.

The accident with the Citation, although crew related, had nothing with crew experience. There was no suggestion that the ditching of the Super Puma in 2010 had anything to do with maintenance.

Apparently the S76 is very similar to the S92, just like the Bell 426 is similar to the Bell 412 I guess.

It's obvious that one of the local operators is unhappy that despite their paying bribes to the NCAA, Bristow is still the largest operator in Nigeria (and the vast majority of civil trained Nigerian pilots, including those working for its competitors, have had their training paid for by Bristow.

pilonrock 10th Feb 2016 13:34

It was Devine intervention.
 
I'm sure in you dig into local newspaper articles before the ditching, you will find clear evidence that several local goats had chronic diarrhea several days prior to the incident. More research and the indicators are there. Predicting the event should have been a no brainier! Odd how senior mgmt didn't predict it. SOPs ? Nonsense! Most Devine messages take precedence, they are inaudible to most except Nigerians and are coded through large speakers in most cases with the base cranked beyond the normal range of human hearing. Gods doing, nothing else!


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