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SAR S-92 Missing Ireland

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SAR S-92 Missing Ireland

Old 17th Apr 2017, 13:53
  #1121 (permalink)  
 
Join Date: Sep 2007
Location: Somewhere in the Baltic Sea
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Originally Posted by AAKEE View Post
Seen the statement before in this tread about the wheather radar.
Newer used a Wx-only radar, but I have used and am using Wx+SAR-radars( including Primus 701A wich I think is used in the S92 SAR?)
In my opinion these radars will detect and show small islands and rock regardless of mode and that they are safe and for awoiding terrain when flying over sea. Of course, as with all equipment, you need to be trained with to use it and I think we can safely assume that this crew was trained.
Earlier days of SAR only had the SAR/Wx-radar to rely on, combined with paper maps/sea carts for close-to-land operations, at least where I come from. In my world the radar picture superseeds moving map if seing ground/osbtacle on the radar( of course you should use all system that adds on SA).

I would absolutely think that the radar could be trusted, and that the radar should have been one of the first slice of the swiss cheese. The EGPWS should be one of the last. Said to see that it did not do the work this time.
Well said AAKEE!

Unfortunately 10 nm scale is not that perfect to detect obstacles within range 1,3-0,6 NM.
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Old 17th Apr 2017, 13:57
  #1122 (permalink)  
 
Join Date: Oct 2012
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S76 Heavy, couldn't agree more.....Radar!!!!!!

There are many holes in this piece of cheese that have been discussed....They all played a part, However, simplifying the situation, whether Blackrock was in/not in the database, an Imc letdown, a vmc night letdown etc etc...I don't care what the situation was, really the bottom line comes down to using the radar.. This IS your primary piece of Equipment that will save the day...When I used to fly offshore, even night VMC letdowns into the blackness, play with the radar, use the different modes, tilt, adjust, re-adjust, check all clear ahead, start the letdown...during the whole procedure, in any turn, the level off, I'd still be adjusting the tilt, etc, re-look where you are going, keep the communications going, and if the other pilot told me there was now a return , even if I was expecting something there, I wouldn't assume it was x until I could clearly see it, and if not visible, climb or turn well away until visual, etc.. and even though I am PF, I'll now take a glance too, see what's ahead, work together as a crew, not just take his/her word for it...and adjust accordingly...etc...I have used FLIR but we didn't have that offshore, didn't have other crew members apart from the other pilot, the rigs were in the gps but tankers passing through were not, doesn't matter, use the radar...don't need flir, gps doesn't show every possible target...doesn't matter, use the radar....and if I was x miles away from my destination and I was told to come left/right, alarm bells would have gone off?? Why come left or right? what the hell is out there? I am gobsmacked at the lack of use/poor comms from the radar operator and almost blasť attitude from the P1? If you were unfamiliar with an area too I would have been even extra cautious...used properly, at some point in the turn a large blob on the radar screen would have caught your attention even if it was off the screen on the last known approach track which has been suggested here due to drift!. It is easy in Hindsight to criticise, but as professionals, I am amazed and saddened at the total waste of life of 4 crew members, who I have the utmost respect for going out day and night to save others....
SAR is different from offshore, letting down towards land/rocks is different to letting down towards rigs, I have done both, but, the RADAR was still the primary tool to stop you hitting something....

RIP all the crew members, and I wish all the family members find the strength to get through this difficult time......
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Old 17th Apr 2017, 13:57
  #1123 (permalink)  
 
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Originally Posted by [email protected] View Post
... with NVG on they would have seen the rock long before it became an issue. ...
Agreed.

---------------
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Old 17th Apr 2017, 14:13
  #1124 (permalink)  
 
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Brutal wrote:

SAR is different from offshore, letting down towards land/rocks is different to letting down towards rigs, I have done both, but, the RADAR was still the primary tool to stop you hitting something....
Long time since I did an ARA, but isn't the SOP to have the radar at 2.5nm?
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Old 17th Apr 2017, 14:19
  #1125 (permalink)  
 
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What will be interesting is how the operators deal with the crew issues which have been noted and will inevitably form part of the final report.

Will the operators and regulators hide the shortcomings in equipment and procedures behind any failures of the crew to monitor the radar and conduct the letdown correctly?

We are often told about 'just-culture' in Safety Management Systems but how will that stand up to pressure from the operator to avoid and blame/litigation?
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Old 17th Apr 2017, 14:21
  #1126 (permalink)  
 
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Originally Posted by Fareastdriver View Post
I put forward this theory in post #143

The cockpit transcript was depressingly similar. The captain advised the co-pilot (pf) to turn around. As he was Chinese without Level 4 in English this was relayed by the interpreter. He queried the heading and this also went back and forth through the interpreter. When it was resolved he commenced the turn but half way round the helicopter struck the top of the hill killing all three.

The radar was found to be 5 degrees nose up which would have masked the coast close up in front of them.
Sounds like ALT a great friend and mentor... 😢
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Old 17th Apr 2017, 14:31
  #1127 (permalink)  
puntosaurus
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The thing which is hardest to explain here is that we know the copilot looked at the radar screen about 30s before impact and called a small radar return at 6nm/11 o'clock. At this point he was just under 1nm from Blackrock, so what happened to the Blackrock return ?

Assuming the radar return was Duvillaun More then it's about 0.5nm across from the radar's perspective. At 6nm the circumference around the aircraft is about 36nm (6nm*2pi). Let's say the radar sweeps out 60 degrees of that, ie. 1/6th of the circumference or a 6nm arc. It follows that Duvillaun More would have a lateral extent of 8% (0.5/6) of the sweep.

Run the same calculations for Blackrock which presents a lateral extent of about .12nm at about 1nm range and it turns out that it would occupy a similar amount of the sweep. Given the heading and drift of the aircraft those returns might well have been adjacent on the sweep although very different distances away.

It has also been suggested that Duvillaun More and Blackrock would have painted very different pictures on the screen because of the different topography and distances involved. I'm thinking Duvillaun More may have been more of a blob, but Blackrock has some 'stealth' features, sharp edges and flat surfaces angled away from the radar. In addition there might have been some clutter on the screen which might still include some weather in the solid IMC above even though the radar was in ground mapping mode.

I'd love to know from a SAR driver with lots of experience of interpreting weather radar pictures using the fit in this aircraft to speculate on what the radar picture might actually have been. Somehow the Blackrock return was misinterpreted but how ? Would the Carrick Islands just in front of them have appeared on the screen and lulled them into believing that the Blackrock return was a similar low feature ? Could Blackrock have looked like sea clutter or weather somehow ? Could Blackrock itself have created a local weather effect that masked the island ?

Last edited by puntosaurus; 17th Apr 2017 at 14:51.
 
Old 17th Apr 2017, 14:58
  #1128 (permalink)  
 
Join Date: Oct 2006
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It's a sad fact of life that if a fully serviceable aeroplane flies into something it's not the aeroplane's fault.
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Old 17th Apr 2017, 15:01
  #1129 (permalink)  
 
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Its an interesting point Punto. I am not SAR but a few ARAs in the past. I generally aimed the RADAR slightly below the horizon, maybe 3 degrees nose down, turned the gain to full, always in WX mode, and then backed off the gain to remove the sea clutter, leaving (what I believed) to be the hard bits behind.

I recall most people I flew with did mostly the same procedure. Although an handful would obsess about which mode they wanted. I think "Search" modes featured a lot in these discussions, but if in Command, I always resolutely insisted on the WX mode and the technique I have described.

Having written this, and now as we review this accident, it seems bizarre that we have not formally mandated an exact technique for setting the RADAR up. (Maybe in some other organisations they have).

Anyone have any other techniques they would like to share or has anyone been subjected to a "Mandatory" setup.

In fact I change my story a bit having thought about it. What I did was never relied on the angle of dangle indication. I would turn the gain full up, turn the head down until I had total sea clutter, or in calm, targets crystal clear where I expected them to be. Then I backed off the gain until the sea just about disappeared. Funny what comes back when you read what you wrote previously. Nope, I never used the angle of dangle thingy.
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Old 17th Apr 2017, 15:33
  #1130 (permalink)  
 
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There could be some cognitive issues here regarding what the crew were seeing versus what they were expecting to see.

If I was running the investigation I would be insisting on an S92 flying the same profile (day VMC) in the same configuration to have a look at the indications prior to the point of impact. Obviously you can't replicate the weather conditions so the radar returns would be a variable but it would be a very useful exercise.
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Old 17th Apr 2017, 15:39
  #1131 (permalink)  
puntosaurus
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It's Ireland. It's very easy to replicate the weather conditions.

Less facetiously, I think that is a great idea. I wonder if with the sharp vertical extent and it's proximity, and it's stealthy qualities, Blackrock looked very similar at 1nm to the Carrick Islands at this point .2/3nm away. If the crew could rationalise away the Carrick Islands, then it would be easy to do the same for Blackrock.
 
Old 17th Apr 2017, 17:02
  #1132 (permalink)  
 
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On the CVR it has the co-pilot reporting a contact at 11 o'clock, 6 miles at 32secs or about 0.75 n.m. before impact. Drumacappel wasn't at six miles then; it started at about 5 miles. What was at six miles was the highest point of the island on the eastern side. A radar tilted at 0 degrees would have seen the coast, one titled up wouldn't.
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Old 17th Apr 2017, 17:14
  #1133 (permalink)  
 
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From personal experience with marine radar, the images generated with a range scale set to three miles or less are pretty useless due to sea clutter. Also at these ranges there is the possibilty of very strong radar returns activating protective devices that are designed to prevent radar transmitter energy from destroying the very sensitive receiver section. In effect, the more powerful the radar return, the more likely that the receiver will be desensitised and effectively nothing will be displayed on the screen.

This is a very simplistic explanation of why they maybe saw nothing on the radar screen, as there are numerous settings that all interact and affect the radar picture. Depending on the wavelength of the radar, cloud and rain reflections can also absorb or reflect sufficient energy to blind the radar receiver at close ranges.

I had several years mucking about with the marine stuff including installations and commissioning, if anyone feels the need to argue or debate the details via PM.
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Old 17th Apr 2017, 17:29
  #1134 (permalink)  
 
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not my league but were they Night VMC at 200 ft and did not see from afar the light on Blackrock flashing? Was the light house working 100%?
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Old 17th Apr 2017, 17:35
  #1135 (permalink)  
 
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Originally Posted by Michael Gee View Post
not my league but were they Night VMC at 200 ft and did not see from afar the light on Blackrock flashing? Was the light house working 100%?
It's likely the light was in cloud.
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Old 17th Apr 2017, 18:10
  #1136 (permalink)  
 
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And that the 'heads-in' mindset along with the likelihood they didn't even realise there was a lighthouse there meant they weren't looking for it.
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Old 17th Apr 2017, 18:28
  #1137 (permalink)  
 
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Originally Posted by SASless View Post
Al-Bert,



Why would an Approach Plate for a preplanned IMC Procedure that had been surveyed, trained for, checked, and used incorporating the Gucci abilities of the FMS and other equipment cause an accident like this?

I submit the absence of that is the main contributing cause of this accident.

Times change as does technology....and we should change with it.

Eacott Reminded you that Steam Age 61's had their bad days and you then admitted post one such bad day....changes in the way business was done was effected.

So why not do the same after this one?
Sorry SAS - I don't understand your post - yes times change, in this unfortunate crew's case for the worse. Over complication of navaids in an overworked cockpit, a procedure mistakenly flown because it wasn't an IFR plate, unreliable data inputs to the nav kit, rear crew not totally involved in the procedure (poor CRM) - all or any of these things may have contributed to the cfit. Mr Eacott referred to an early RN SK (not a 61) cfit - I assume RN procedures changed post that crash and the RAF procedures followed, and in time incorporated GPS and NVD's. Tragic accident to an experienced crew that shouldn't have occurred and yes, I've been to Blacksod on a few occasions too.
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Old 17th Apr 2017, 18:32
  #1138 (permalink)  
 
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Originally Posted by [email protected] View Post
And that the 'heads-in' mindset along with the likelihood they didn't even realise there was a lighthouse there meant they weren't looking for it.
And if they weren't looking for it, it is possible they weren't monitoring the other sources of information to look for it either. I didn't see if the report has details on the radar range settings. Can the radar range be set separately from the display range?

Does anyone know what sensor configuration the EO/IR turret has? Is the aircraft capable of displaying two video outputs at once?
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Old 17th Apr 2017, 18:38
  #1139 (permalink)  
 
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Any helicopter weather radar I have used (excluding that fitted to civilian AW machines) have been good down to half a mile for obstacle avoidance as long as it is in the correct mode. It's no good leaving it in wx mode because the gain is then fixed and non adjustable in order to optimise the observance of Level 3 weather returns which equate to an active thunderstorm (or very heavy rain).

In absolute contradiction of Double Bogey above, use of the correct Search mode is vital. There will be at least one which is optimisied for short range selection which will reduce the pulse length and increase the pulse frequency. When level at 200' or thereabouts, tilt control should be set about level which will give about +/- 3 to 5 degrees of scan above and below the horizontal depending on the diameter of the aerial. The larger the aerial, the narrower the beam will be in both horizontal and vertical plane. If the radar is set correctly, Black Rock should have been painting loud and clear.
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Old 17th Apr 2017, 18:43
  #1140 (permalink)  
 
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DB

You might want to check your memory as the gain function does not work in weather mode. The important point about using search 1 or 2 modes when looking for a rig or ship is that it is short range (20nms or less) and the PRF is increased. To put it simply, higher PRFs transmit more energy in a given time, which produces stronger and more defined radar reflections. The best picture will be provided by a combination of search modes, tilt and appropriate gain setting.
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