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-   -   SAR S-92 Missing Ireland (https://www.pprune.org/rotorheads/592162-sar-s-92-missing-ireland.html)

[email protected] 14th Apr 2017 16:27

In that article in glenbrook's link, the main thing the creator of GPWS acknowledges is the limitations of the database - does that fact get included in any training?

roundwego 14th Apr 2017 16:34

SASless, you said


The question about that absent data lies with the Operator as the system has the ability for User additions to the Database. The data on Blackrock should have been there no doubt.....but there are limitations to any system when it comes to the areas the systems memory will be programmed to cover. In all likelihood the database area of coverage did not anticipate low level flight operations near Blackrock such as the ICG performs.
Are you sure you are correct in your statement about user data being able to be added to the EGPWS database? My understanding is that any new obstacles etc has to be notified to the equipment manufacturer for inclusion in the very infrequent updates. i don't think it is reasonable to expect the operator to check the whole egpws database for correctness.

I know the egpws database has its origins many years ago when computer memory was expensive and the database had extremely low resolution to keep the file size small. An obstacle such as a radio mast would show up as a 1km square block on the screen and the mast would not necessarily have been in the centre of the square. In fact, if the mast was exactly at the meeting point of 4 blocks on the map grid, it would show up as a 2x2 km block. I am not aware that the database has become higher resolution in recent times. Having said that, there is no excuse for Black Rock not to be in the database.

(I may be incorrect in the size of the egpws map grid blocks because, being an American product, I would have thought the units would have been non metric)

noooby 14th Apr 2017 16:35

So why did no member of the crew notice a honking great lighthouse shining at them?

Even in IMC, when you get close to it, it will light up the inside of the cloud.

When you're VMC and co-alt, it should be shining right into the cockpit, and those things are BRIGHT!

Lighthouse service says it was on at the time (as in, remotely switched on), but was it actually working? Why would it not have been noticed? The first anyone seems to know of an obstacle (despite the Co-Pilot having Radar displayed in GMAP mode on his MFD), is when the crew in back ask for a right turn.

The 701 radar has pretty good ground mapping. And it will do it to a close enough range that objects don't disappear from the display until you're nearly on top of them (unlike the 660 radar), so why no visual of the light and no radar sighting of a b***dy great rock in front of you?

noooby 14th Apr 2017 16:38

crab, are crew trained to appreciate that EGPWS is not approved for navigation? Or is that fact passed over and they learn to trust it more than perhaps they should?

Although, with their speed, altitude and the fact that the gear was down, warning and caution messages relayed to the crew would be limited and different to a situation where they were faster with the gear up.

[email protected] 14th Apr 2017 16:46


crab, are crew trained to appreciate that EGPWS is not approved for navigation? Or is that fact passed over and they learn to trust it more than perhaps they should?
Good question nooby and I think it will come back to the reliance on automation again - we get given the new gucci kit and don't expect it to go wrong.

The main difference between the Mk 3 and the Mk 3A Sea King was the AP - the Mk 3 was single channel, steam driven and it's failure modes could easily put you in the water so the crews watched it like a hawk. The 3A had a duplex digital AFCS which hardly ever went wrong, had benign failure modes and was very good so crews trusted it - sometimes more than they should have.

The S92 is in another dimension as far as capability goes so it is very easy to see how complacency can creep in.

212man 14th Apr 2017 16:49


Originally Posted by roundwego (Post 9740295)
SASless, you said



Are you sure you are correct in your statement about user data being able to be added to the EGPWS database? My understanding is that any new obstacles etc has to be notified to the equipment manufacturer for inclusion in the very infrequent updates. i don't think it is reasonable to expect the operator to check the whole egpws database for correctness.

I know the egpws database has its origins many years ago when computer memory was expensive and the database had extremely low resolution to keep the file size small. An obstacle such as a radio mast would show up as a 1km square block on the screen and the mast would not necessarily have been in the centre of the square. In fact, if the mast was exactly at the meeting point of 4 blocks on the map grid, it would show up as a 2x2 km block. I am not aware that the database has become higher resolution in recent times. Having said that, there is no excuse for Black Rock not to be in the database.

(I may be incorrect in the size of the egpws map grid blocks because, being an American product, I would have thought the units would have been non metric)

Yes, and the report states that in the quote from Honeywell. It's done by the operator providing the data to Honeywell and they include it in the update cycle.

cncpc 14th Apr 2017 16:55


Originally Posted by Skylark58 (Post 9740102)
R118 had already landed at Blacksod to refuel, presumably using the same route guide.Would they have followed the same let down and approach profile as R116?

I asked that and another poster pointed out that R118, out of Sligo, was much more familiar with the area and would have known of Blackrock and the need for a higher altitude in that part of the approach.

roundwego 14th Apr 2017 17:00


Originally Posted by 212man (Post 9740312)
Yes, and the report states that in the quote from Honeywell. It's done by the operator providing the data to Honeywell and they include it in the update cycle.

That's what I thought. I read your statement as the operator having the ability to add data directly to the aircraft database without having to involve Honeywell.

I think the discussion about EGPWS is a bit of a red herring as in the described aircraft configuration, no warning would have been given even if Black Rock had been in the database as the system would have assumed the crew were making an approach to land on the helipad - low speed, gear down.

rotorspeed 14th Apr 2017 17:03

SAS

"One Man's Opinion here.....this Crew were handed a Time Bomb by Management, Training, and Safety. The Operator failed to change from old ways and failed to embrace new technology that requires a change of Mindset and Safety Culture."

That's a pretty damning statement about the management of this SAR operation. All those involved will no doubt have pride and strive to be professional, like the flight crew. What information are you relying upon to conclude that?

Galwayguy 14th Apr 2017 17:18

Did the crewman, who spotted the Island, give a strong enough warning ? Is there a language protocol that means you are giving an immediate instruction rather than an advisory ?

roundwego 14th Apr 2017 17:36

Alphanumeric wrote;-


Originally Posted by alphanumeric (Post 9740332)
They crashed into the ground as they did not realise the terrain was higher than sea level.

All this talk of databases, waypoints, EGPWS, safety culture, procedures etc does not detract from the fact that there was no proper two-crew approach brief* that discussed the elevation of Blackrock and how the approach was going to be conducted. This is standard offshore 2-crew procedure.

*Just like there was no proper 2-crew departure brief in the G-LBAL accident.

Yet another uneducated conclusion. How do you know there was not a proper two crew approach brief? They both acknowledged they were unfamiliar with the area. The report does indicate there was an approach brief but acknowledges there was no mention of the presence of Black Rock nor the lighthouse. The big question was why? I cannot believe the crew were anything but conscientious in carrying out there task so one can only assume, there was a deficiency in the way the terrain information was presented or the way the procedure was designed. As I mentioned previously, I don't understand why the prescribed track went directly overhead a 300' high lump of granite and brick.

Alphanumeric, to blame the crew in such simplistic terms puts your own professionalism in doubt.

Thunderbirdsix 14th Apr 2017 17:53

Any time I saw Rescue 115 or 118 head to Blacksod on Marine Traffic they route along the Coast Line, Rescue 115 heads up over Galway Bay to Clifden then along the coast to Blacksod, 118 departs Sligo straight along the coast then down to Blacksod, I guess with 116 coming cross country the first coastline they encounter is Blacksod

boatmad 14th Apr 2017 17:55


Originally Posted by roundwego (Post 9740354)
Alphanumeric wrote;-



Yet another uneducated conclusion. How do you know there was not a proper two crew approach brief? They both acknowledged they were unfamiliar with the area. The report does indicate there was an approach brief but acknowledges there was no mention of the presence of Black Rock nor the lighthouse. The big question was why? I cannot believe the crew were anything but conscientious in carrying out there task so one can only assume, there was a deficiency in the way the terrain information was presented or the way the procedure was designed. As I mentioned previously, I don't understand why the prescribed track went directly overhead a 300' high lump of granite and brick.

Alphanumeric, to blame the crew in such simplistic terms puts your own professionalism in doubt.


The report clearly mentions that the approach briefing notes and moving map contained data showing blackrock and its heights etc . It did not contain any comment as to whether the crew accessed such information

[email protected] 14th Apr 2017 19:43


All this talk of databases, waypoints, EGPWS, safety culture, procedures etc does not detract from the fact that there was no proper two-crew approach brief* that discussed the elevation of Blackrock and how the approach was going to be conducted. This is standard offshore 2-crew procedure.
And this was not an approach to Blackrock as a LS - that would have required such a brief - this was part of a letdown to cloudbreak to get to Blacksod.

Therefore all the talk about databases, GPWS and especially the construction of the procedure is absolutely valid.

Do you include a brief during a procedural letdown to a rig on EVERY WP in the FMS? I suspect not - such detail would be confined to the final approach to the LS/rig itself.

cncpc 14th Apr 2017 19:51


Originally Posted by alphanumeric (Post 9740332)
They crashed into the ground as they did not realise the terrain was higher than sea level.

All this talk of databases, waypoints, EGPWS, safety culture, procedures etc does not detract from the fact that there was no proper two-crew approach brief* that discussed the elevation of Blackrock and how the approach was going to be conducted. This is standard offshore 2-crew procedure.

*Just like there was no proper 2-crew departure brief in the G-LBAL accident.

All terrain is higher than sea level.

The accident report distinctly says there was an approach briefing. It can be inferred that the crew was unaware of Blackrock as a piece of terrain at 300 feet. It does seem that Capt. Fitzpatrick was aware of rocks there as she knows why the altitude warning sounds, but she thinks they are over the waypoint. So she knows the waypoint is over "terrain", but obviously doesn't know its height. In fact, even though they are only at 200 feet, she is not concerned by the alerter.

What does APBSS mean at the top of that chart we are considering some kind of buck shee or homemade approach "plate"? On looking at it, it seems that it is more likely a VFR day or night or reduced viz transit route from heliport to heliport as Blackrock and Blacksod are terminus points. There is no real indication that some approach procedure for Blacksod keys on Blackrock or the waypoint.

Inbound to Blackrock from the east, it is clear that the intention is to land at Blackrock heliport. It is a straight in approach with a presumption of VFR conditions or at worst reduced viz. There is no scenario of approaching it from the ocean to the west. That may provide an explanation at least why this seems to be a very inadequate IMC procedure. It wasn't meant to be.

Leaving Blackrock also assumes you are lifting off from the heliport for Blacksod, which does have a bit of an indirect routing. There is no scenario in which you pass over Blackrock.

For whatever that is worth, the question then is whether this "approach" is programmed into the FMS, or whether each waypoint is sequentially selected manually by a Direct To button and the waypoint. The error in that would be assuming it is an IFR approach.

Search&Rescue 14th Apr 2017 19:53

Noooby

Maybe it was one important detail that most likely they didn't have the radar target (a b***dy great rock) in front of them! I may be wrong, but it is my understanding that the heading was approximately 120 degrees and due to the wind the track was 098 degrees. And if you have 10 NM scale on your radar, it is not always that easy to realise that you are drifting to an obstacle if you are pretty close (e.g. 0,3 nm) with that kind of drift angle... But I agree that the 701 radar is very good for ground mapping...

Al-bert 14th Apr 2017 20:12


Originally Posted by Search&Rescue (Post 9740485)
Noooby

Maybe it was one important detail that most likely they didn't have the radar target (a b***dy great rock) in front of them! I may be wrong, but it is my understanding that the heading was approximately 120 degrees and due to the wind the track was 098 degrees. And if you have 10 NM scale on your radar, it is not always that easy to realise that you are drifting to an obstacle if you are pretty close with that kind of drift angle... But I agree that the 701 radar is pretty good for ground mapping...

and 'children of the magenta' deride the Sea King blind arc! :=
Maybe a 'clear blind arc left' might have helped in this case? :(

[email protected] 14th Apr 2017 21:27


Inbound to Blackrock from the east, it is clear that the intention is to land at Blackrock heliport. It is a straight in approach with a presumption of VFR conditions or at worst reduced viz. There is no scenario of approaching it from the ocean to the west. That may provide an explanation at least why this seems to be a very inadequate IMC procedure. It wasn't meant to be.
No, there was never any intent to land at Blackrock - why on earth would there be? Blackrock was 2 things - firstly a WP in the company letdown route to get to Blacksod and secondly a bloody great rock on the way to do so. The fact that they were overlaid on a procedure without any clear indication of the threat is the real issue here.

Al-bert - agreed, you and I both know that it would not have happened in a SK letdown because we had a dedicated radar operator rather than an over-tasked co-pilot to stop us bumping into things.

Al-bert 14th Apr 2017 22:03


Al-bert - agreed, you and I both know that it would not have happened in a SK letdown because we had a dedicated radar operator rather than an over-tasked co-pilot to stop us bumping into things.
Exactly Crab!

Democritus 14th Apr 2017 22:08


Originally Posted by cncpc (Post 9740483)
.....Inbound to Blackrock from the east, it is clear that the intention is to land at Blackrock heliport. .....

That would be quite impossible in a S92 due to its size. I've landed many times on the Blackrock pad, but with a much smaller Bo105 - admittedly the last time was almost 45 years ago - and from photos the pad hasn't increased in size since then.


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