R116 Accident AAIU report discussions

Yes it is a long time when you consider that the recommendations of the final report may contribute to preventing further accidents.

It wasn't a case of the crew having incorrect charts. I think the suggestion tonight was that the root of the problem was the OSI chart, published by the state, was inadequate. Since all other navigation databases are ultimately using the official charts as reference, then none of the systems which could have drawn the crews attention to the obstacle did.

Seems to have been a systemic failure of the SMS at CHC in that safety reports were not being resolved in a timely manner, if at all. The IAA was not conducting proper oversight to enforce CHCs own procedures.

They had reference documents for each approach and it was listed as an obstacle on the Blacksod approach briefing document. According to Prime Time it was mentioned 4 times in that particular document but there was a perception among the pilots that these reference documents were unreliable and often had misinformation on them. The impression I got was that they were not used much by the crews.

Here it is.

Executive Summary.

Full report.

I've only read the ES so far but the operator do not come out well from this. The reference to fatigue alone is worrying.

"R118 advised MRSC Malin that strobes had been sighted in the water. The Crew of R118 informed the Investigation that shortly thereafter they identified a life raft in the water and that a casualty was floating in the water nearby. The winchman was deployed to recover the casualty. ... The helicopter was re-positioned several times but each time the winchman got close to the casualty, wave action separated them. Achill lifeboat arrived on scene at this time. R118 directed it to the casualty’s location, recovered the winchman and withdrew a short distance so that the lifeboat could attempt to recover the casualty."

Jesus, that must have been heart-breaking for the crew of R118 😟

"To understand why Black Rock had not been included in the EGPWS databases at the time of the accident, the Investigation asked the EGPWS manufacturer about its processes for obtaining topographic data. The EGPWS manufacturer informed the Investigation that data was originally sourced from multiple Russian Military Topographic maps which were processed by its supplier and delivered to the EGPWS manufacturer in Digital Elevation Model (DEM) format covering Ireland."

Looks like the EGPWS terrain data came from Russian sources, OSi here only supplied digital versions of paper maps.

The data could just have easily come from NASA via their SRTM datasets which are in common use.

Maybe the OSI should be supplying digital terrain data for all offshore obstacles within Irish territory.

They could well have used SRTM data also, but the distance between grid points (90m) for the data available for Europe is insufficient to accurately represent small "pointy" objects like Black Rock. I have some experience of using SRTM data in digital mapping applications for hillwalking / mountaineering applications and while it's OK for smoother terrain, it falls short when things get steeper and sharper and as a result of this people in the mountaineering community, specifically the SMC (Scottish Mountaineering Council), produced a corrected version, filling in voids, correcting obvious errors (usually caused by steep cliffs producing unwanted reflections of the radar signal).

I don't know what the grid spacing of this Russian military data is, but the issue is that with small objects like this, you have no idea of where in the grid pattern the peak will fall, if it's slap bang in the middle of four data points the elevation calculated by interpolating between those four points in the DEM will possibly be much lower. As an experiment, I popped the coordinates of Black Rock into one of my mapping programs using an SRTM derived DEM as a waypoint (Black Rock, although it appears on the paper map of the area in an inset, doesn't appear on any of the OSi digital map tiles I have) and hovering over the waypoint I get an elevation of 13m, much lower than what it is in reality.

I would imagine that from the EGPWS manufacturer's POV, they don't want to be dealing with multiple national agencies supplying DTM data and then merging these datasets and ensuring no gaps etc. Much simpler to acquire one large world dataset from the big boys like NASA, Russians and likely China have same sort of data. Would cost have also been a factor?

That's what it looks like to me - that there was another point or paragraph that discussed the crews role and that was removed, but the edit wasn't followed through.

Wasn't it the case that the route they had programmed in was one that was actually originally intended for the refuelling run to and from Blacksod?

Seems a no brainer to me. If they can supply it, why wouldn't they (going forward)? Or if they won't then some other state agency should. Doesn't seem reasonable to be relying on other countries doing it.

Yes but Black Rock is rather larger than 90 metres in width!! https://en.wikipedia.org/wiki/Blackrock_Island,_County_Mayo

It's not a small pointy object but a substantial feature - could be 400 metres by 300 metres and higher than Liberty Hall. With a lighthouse perched on top.

I think what they are trying to do is report that there were errors and lapses of judgement which led to the only probable cause of the accident which was:-

“The Helicopter was manoeuvring at 200 ft, 9 NM from the intended landing point, at night, in poor weather, while the Crew was unaware that a 282 ft obstacle was on the flight path to the initial route waypoint of one of the Operator’s pre-programmed FMS routes.”

The report goes on to list a number of contributory factors but these are not ranked in any order of importance.

What the report is really saying that there is no way that the helicopter should have been flying at that altitude and in those conditions while still over 16km from their intended landing point. I think that the report is also saying in point number 10 that, irrespective of other considerations, the flight crew made errors which caused them to be do what they did. I assume that the investigating team, in an effort not to apportion blame to any individual, has not specified precisely what errors or lapses of judgement were made by the flight crew while at the same time being obliged to report that errors were made.

This report does not really explain why the accident happened.