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Bristow S76 Ditched in Nigeria today Feb 3 2016

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Bristow S76 Ditched in Nigeria today Feb 3 2016

Old 14th Feb 2016, 00:54
  #181 (permalink)  
 
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There have been some (perhaps) tongue-in-cheek, (perhaps) flippant remarks in the forum about the crew likely to be considered for promotion for a safe job well done. Out of curiosity, what happened to the BHNL crew of 5N-BMM (crash at Port Harcourt in 2011)? Did they get promoted, returned to duty, retired? Just wondering.

@industry insider: yes, of course the aircraft is a write off, that happened the moment it turned turtle in salt water. Lifting it out of the water the way they did didn't help either. It would need a lot of spin not to describe such a write-off as anything but an accident. Not only concerned clients, I bet the insurer is feeling a little grumpy about it also. $250K BHNL investment to train a national crew (or whatever the number is) is cheap in comparison to the excess payable on a $7 million hull loss, plus insurance premium rises for years to come. Just saying.
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Old 14th Feb 2016, 03:05
  #182 (permalink)  
 
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The S76 can be despatched for VFR with an MEL deferral on both AFCS inoperative
I think I'm correct in saying when PHI took delivery of their first 76s they didn't even have them fitted. Pilots are employed to work (fly), why make it easier for them. Same attitude still prevails in the FW world re fitting autopilots.
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Old 14th Feb 2016, 03:14
  #183 (permalink)  
 
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@megan. You are correct. AFCS was a customer option with early model S76A.

DDAFCS and FD mode operation leads to so much bewildering confusion in the cockpit sometimes I'm left to wonder whether crews are better off without it at all. I have seen the simulator crashed so many times simply because of mode confusion and wrong button pushing. Stick to hands on VFR flying and they're OK, give them options with buttons to push and it can rapidly turn to worms. Where divine intervention is relied upon in such situations never results in a successful outcome. Just saying, again.

Last edited by gulliBell; 14th Feb 2016 at 03:25.
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Old 14th Feb 2016, 04:02
  #184 (permalink)  
 
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Originally Posted by gulliBell
@megan. You are correct. AFCS was a customer option with early model S76A.
Well, sort of. Sikorsky intended to make their own AFCS, which was to be Phase 3, but it never happened and we had Phase 1/2 SCAS only. Those customers who opted for the Phase 3 AFCS got their money back (I think) and the SPZ 7000 was certified instead.

So for the early formative S76 years there was only a SCAS, with two pilot requirement, yet it worked very well and showed what a stable IFR platform the S76 is.
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Old 14th Feb 2016, 07:29
  #185 (permalink)  
 
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John...

... or, as we did at Air Hanson, opt for the HeliPilot. I think the SPZ7000 came along with the 'B' model but thinking back into the last century is taxying the grey matter a little too much to be sure.

G.
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Old 14th Feb 2016, 08:01
  #186 (permalink)  
 
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I just remember stories from the old timers back in the old days who used to tell me how easy I had it flying a 76 equipped with an autopilot because the ones they used to fly didn't have such a luxury.
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Old 14th Feb 2016, 08:08
  #187 (permalink)  
 
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And this little bit of grey matter is only put straight by reference to the old S76A Flight Training Manual! Sikorsky reference the Phase I/II and the (expected) Phase III as an AFCS, but it was only a SCAS. HeliPilot didn't come along until much later.

gulliBell, the S76 really was delightful to fly with Phase I/II as we didn't know any better! On an ILS that I was flying into Perth Dave Whyte reached over, tapped the AI and declared it was broken because attitude had been unchanged all the way from the OM
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Old 14th Feb 2016, 08:18
  #188 (permalink)  
 
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In my day, the Hiller 12E, Whirwind s3 and 206 didn't have any stabilisation at all

Very tongue in cheek

TC
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Old 14th Feb 2016, 08:35
  #189 (permalink)  
 
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...and once I was coming in from offshore in an old A model with Capt [redacted] and he turned off both the generators and the battery and the old girl still hummed along nicely without the slightest disturbance what-so-ever. If I remember, with one HP out you had to slow down, but with 2 out you could still maintain warp speed to ensure you weren't the 2nd last ship home and thus avoid warming a seat in the crew room until the last ship crossed the coast.
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Old 14th Feb 2016, 12:20
  #190 (permalink)  
 
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dangerous words but my view is that if you can't fly an S76 with both AP's out you maybe shouldn't be flying one. It is well within the capabilities of any decent pilot. We used to do AP out training from take off to landing so it isn't beyond possible. I've even had a TRE 'accidently' take out both ap's just as I lifted from a rig deck!!!! Always better to have a little warning tho.
In a two crew S76 if you think the person flying next to you needs a challenge, just switch off the collective trim switch and see how long it takes for them to notice and how they deal with it.(disclaimer:im not suggesting you do this without prior agreement and warning, oh and when finishd dont forget to switch back from SAS mode )
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Old 14th Feb 2016, 14:03
  #191 (permalink)  
 
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Of course if it is a autopilot issue we don't yet know exactly what. I'll recount an incident we had on a AS332L some years ago: Approaching a rig the aircraft suddenly started to shake rhythmically. The crew felt there was something dire wrong with the rotor system and warned the pax that a ditching was possible, but in the event they carried on to the helideck. It eventually transpired that a vertical gyro had got a wobble on and this was, through the autopilot, putting in spurious rhythmic control inputs that emulated rotor imbalance.


So faced with a suspected main rotor failure or very serious issue, it is perhaps not too surprising that the crew didn't think of punching out the AP as one would prefer to have as much going for one as possible when dealing with an emergency, as opposed to making life more difficult by killing the AP. In this case it was all over fairly quickly due to their proximity to the rig but had it happened in open ocean, who know what they might have done. It is very easy to pass judgement in hindsight and from the comfort of the armchair, somewhat harder to get it right with a massive flood of adrenalin and near-panic!
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Old 14th Feb 2016, 14:44
  #192 (permalink)  
 
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Originally Posted by helimutt
dangerous words but my view is that if you can't fly an S76 with both AP's out you maybe shouldn't be flying one.
Of course you shouldn't..... we took delivery of our S76A in July 1980 and it was flown manually, no SCAS or anything else fitted, from West Palm Beach to Conroe, Houston, to have the Sperry autopilot installed. No problem.
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Old 14th Feb 2016, 19:11
  #193 (permalink)  
 
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On the Sycamore you had a nine cylinder radial driving a rotor that had no autopilot, no hydraulics and a pair of trim wheels, lateral and fore & aft, that tensioned springs in the control runs to enable you to exercise what limited control authority you had. Imagine a 332L with the HYD AP out and you have a rough idea of the control forces. There was only one collective so if you where flying from the LHS you held the cyclic with the left hand and the central collective with the right. Occasionally, years later, on the 332L when I was a LHS captain flying the return leg, just to prove to myself that I was keeping up to speed I would do the final approach and landing with the HYD AP out using my left hand on the cyclic and my right hand on the RHS collective.
There were no complaints from either the front of the back.

The Whirlwind (S55 to the Colonials) had no autopilot, it did have hydraulics but no trim, either wheels or chinese hats. There was a friction device but the vast majority of pilots used to screw this right off so as to leave the stick free. This meant that if you let go of the cyclic it fell over and the aircraft followed it.
Amazingly this system lasted for about thirty years and nobody ever lost control.

So you come to the SK76. Take away the APs, trim, FMS and you have a basic helicopter similar to the Whirlwind. You can fly it VFR, IFR, hover over the ground and at a push winch people out of the sea. Wobbles are what used to be known as PIOs (pilot induced occillations). The only time, in my experience, when the 76 is difficult is if you have an engine failiure just before VTOSS. The torque, or lack of torque reaction can catch you out and you may have a couple of swings before you straighten it out.

It may well be that people who being paid to fly the aeroplane have got so many gizmos to fly it for them the they have lost the ability to actually fly it when it really matters.
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Old 14th Feb 2016, 20:19
  #194 (permalink)  
 
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How many PBA failures did you have with the old Phase 1/2? We still had them in the UK where I was working, but I know many people were allowed to fly without them.

Boy those things used to fail a lot!
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Old 14th Feb 2016, 22:06
  #195 (permalink)  
 
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HC

So faced with a suspected main rotor failure or very serious issue, it is perhaps not too surprising that the crew didn't think of punching out the AP as one would prefer to have as much going for one as possible when dealing with an emergency, as opposed to making life more difficult by killing the AP. In this case it was all over fairly quickly due to their proximity to the rig but had it happened in open ocean, who know what they might have done. It is very easy to pass judgement in hindsight and from the comfort of the armchair, somewhat harder to get it right with a massive flood of adrenalin and near-panic!
According to information, the same autopilot issue was evident outbound but the crew landed on the rig without a problem and attempted to troubleshoot (hard to troubleshoot an AP issue with all that metal around and while stationary on a rig) Then after departure when the issue came up again decided to ditch.

One doesn't need a comfortable armchair to suggest what may have been done for an improved outcome.
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Old 14th Feb 2016, 22:54
  #196 (permalink)  
 
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HeliPilot didn't come along until much later.
John, I did my conversion in November '80 and we had the Helipilot fit, think we may have been the first customer.

A question to those who may know, with the A model you had the ability to couple with only one system operational. The C model and 412 needed both systems operational to be able to couple. Certification change or what? Certainly made life more difficult.
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Old 14th Feb 2016, 23:12
  #197 (permalink)  
 
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industry insider
hard to troubleshoot an AP issue with all that metal around
Why, what difference would that make. The metal merely affects the yaw channel if they don't have DG selected for the rig landing.
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Old 15th Feb 2016, 00:37
  #198 (permalink)  
 
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Actually, troubleshooting the AFCS on the helideck was a sensible course of action if the crew suspected an AP problem. As all S76 pilots would know, the test is simple. Whilst on the ground just turn off both AP and press the TEST button on the autopilot controller. This Level 1 test checks the hardware and software considered to be flight critical. LVL-1 PASS or FAIL is shown on the AL-300 on completion. LVL-1 PASS and you're good to go, obviously (the test function is disabled by AOG logic which is why you need to do it on the ground). Any system malfunctions will be indicated with a code that you can refer to in the RFM for more detailed explanation.

If LVL-1 test FAIL whilst offshore, it would be sensible to shut down and seek advice from maintenance. I suspect that advice would be to disembark the passengers and ferry it back to the maintenance base (and there would be paperwork necessary for that to happen I would expect).
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Old 15th Feb 2016, 00:57
  #199 (permalink)  
 
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@Brian Abraham. Correct. That is a good question for Nick Lappos. I don't know the answer either, suspect probably a certification thing (but your A model had Sperry and the 76/412 had Honeywell, right??)
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Old 15th Feb 2016, 01:02
  #200 (permalink)  
 
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Honeywell purchased Sperry in 1986
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