Rescue 116 Crash at Blackrock, Co Mayo(Mod note in post 1)

Dwarf.Shortage · 13-04-2017 11:47PM

TomOnBoard wrote: »

Not as I read it. That crosshairs is very much on the island according to the route map in the report.

You read it wrong.

SimonTemplar · 13-04-2017 11:50PM

A general question please for those more knowledgeable about this than me.

Are aircraft's warning systems (such as an imminent collision with terrain "TERRAIN PULL UP") based on maps rather than onboard instruments "scanning" ahead of the aircraft and detecting terrain?

Steve · 13-04-2017 11:50PM

kona wrote: »

Now if the software had this information he would have heard "terrain terrain pull up"....and pulled up in time with no fuss.

This is inaccurate, the automated call is based on radar altimeter, not the navigation system.

ProfessorPlum · 13-04-2017 11:51PM

kona wrote: »

OK I'll explain this further.

The pilot sets his auto pilot to whatever heading and speed and altitude he likes.
It's dark so he's flying by his instruments. He descends to 200ft at 75 knots and is ticking away nicely. No warnings no nothing the he would expect to hear or see in the event of terrain ahead.

Ticking along nicely, the Winchman sees the rock on his infrared suite and instructs the pilot to change his course 20 degrees to the right.
Unfortunately he's too late.

Now if the software had this information he would have heard "terrain terrain pull up"....and pulled up in time with no fuss.

The pilot relied on his equipment which let him down because the software was wrong and inaccurate. This is what I'm saying.

The point is that EGPWS is not designed and never was intended to be used for navigation. If you hear a GPWS warning, it means you've made a mistake (there are caveats here, but thus isn't one of them). If the pilots were relying on EGPWS to keep them safe, which im sure they weren't, then they could be judged to be flying recklessly.

The point about the approach they were flying being a 'standard company approach' - the company approach describes the approach commencing at BLKMO, and the page of text referred to in the report gives blackrock at a height of 310ft. The approach was flown at that point at 200ft, and the 310ft obstacle was not mentioned in the approach briefing. This would seem to suggest that the approach was not flown as standard. The pictorial of the approach included in the report would not give me a lot of confidence in the quality of standard aporoaches - surely it wouldn't be difficult to design an approach chart that made it easier to appreciate the close in obstacles. That approach was almost waiting to catch someone out.

UsedToWait · 13-04-2017 11:52PM

Irish Steve wrote: »

Yes, in that there is less risk of the automation becoming disoriented in mixed instrument/visual conditions, and it allows the pilot to concentrate on the "bigger" picture rather than having to concentrate hard on flying the machine.
... The automatics are very well capable of doing that task very well indeed.

I really hope that the families get some comfort from this, weird as it sounds..
To me, as a complete outsider to the aviation world, it seems open and shut.
They were given incorrect/incomplete information to complete the job at hand safely.
RIP

kona · 13-04-2017 11:53PM

ProfessorPlum wrote: »

The point is that EGPWS is not designed and never was intended to be used for navigation. If you hear a GPWS warning, it means you've made a mistake (there are caveats here, but thus isn't one of them). If the pilots were relying on EGPWS to keep them safe, which im sure they weren't, then they could be judged to be flying recklessly.

The point about the approach they were flying being a 'standard company approach' - the company approach describes the approach commencing at BLKMO, and the page of text referred to in the report gives blackrock at a height of 310ft. The approach was flown at that point at 200ft, and the 310ft obstacle was not mentioned in the approach briefing. This would seem to suggest that the approach was not flown as standard. The pictorial of the approach included in the report would not give me a lot of confidence in the quality of standard aporoaches - surely it wouldn't be difficult to design an approach chart that made it easier to appreciate the close in obstacles. That approach was almost waiting to catch someone out.

Your completely correct but I didn't really want to.ask why the **** they were at 200ft in night conditions.
Also gpws is there for this exact reason. Of course you don't rely or hope to use it as a pilot.

To put 200ft into perspective the spire is 398ft.

gctest50 · 13-04-2017 11:55PM

Irish Steve wrote: »

Flying a helicopter, especially in the hover, was once described to me as being akin to balancing a tennis ball on the point of a knitting needle..

.

ted1 · 13-04-2017 11:56PM

UsedToWait wrote: »

Irish Steve wrote: »

Yes, in that there is less risk of the automation becoming disoriented in mixed instrument/visual conditions, and it allows the pilot to concentrate on the "bigger" picture rather than having to concentrate hard on flying the machine.
... The automatics are very well capable of doing that task very well indeed.

I really hope that the families get some comfort from this, weird as it sounds..
To me, as a complete outsider to the aviation world, it seems open and shut.
They were given incorrect/incomplete information to complete the job at hand safely.
RIP

Unfortunately it could make it harder for the families. And they will feel a need to chase up why they were giving incomplete info, a mechanical error might have been easier.

kona · 13-04-2017 11:56PM

Steve wrote: »

This is inaccurate, the automated call is based on radar altimeter, not the navigation system.

No its not inaccurate. The forward terrain is determined by the inertial reference system and gps.

The rad alts will determine the height of the aircraft relative to the terrain below as per the information in the gpws.

Irish Steve · 13-04-2017 11:57PM

The article in Wikipedia https://en.wikipedia.org/wiki/Ground_proximity_warning_systemgives a good overview of what GPWS, and the later EGPWS systems do, and how they do it, both Radar Altimeter and GPS information is used to compare against a database of obstacle heights close to the aircraft.

The hole in the Swiss Cheese in this case is that Blackrock was not in the database, so the warning systems couldn't warn them

Gaoth Laidir · 13-04-2017 11:57PM

It would seem that the version of moving map chart selected must not have had Blackrock on it as Capt Fitzpatrick was using this map in her display. Simple situational awareness would have been enhanced had she had Blackrock showing on it. Maybe lack of familiarity with the route played a part in this. Tragic.

The helicopter was equipped with a EuroAvionics EuroNav 5 moving map display which had a number of maps/charts available for selection. The exact information in relation to Black Rock and Lighthouse varied from none, to detailed, depending on the selected map/chart.

....

The Commander had the moving map displayed on her MFD and the Co-pilot had weather radar displayed on his MFD.

...

The CVR recorded the Commander commenting to the other Crew Members on a number of occasions that it had been a substantial period of time since she had previously landed in Blacksod. On one occasion the Commander asked the Co-pilot when he had last been into Blacksod and he indicated that he had not been there recently.

selectamatic · 13-04-2017 11:59PM

TomOnBoard wrote: »

Not as I read it. That crosshairs is very much on the island according to the route map in the report.

This is going to the crux of the issue really, as you pointed out the route was supposedly set direct to waypoint BLKMO as part of the approach route taken to blacksod called APBSS.

Capt. Fitzpatrick clearly stated BLKMO was the little island below as they passed over either Carrickduff or Carrickad so if BLKMO in actual fact was not either of these and was indeed blackrock it's pretty likely this discrepancy was a major factor in the accident.

Now if BLKMO isn't in actual fact blackrock and was indeed either carrickduff or Carrickad it'd seem a lack of awareness re: blackrocks proximity played a key role.

These are the only two scenarios that seem possible to me from reading the report

siobhan08 · 14-04-2017 12:02AM

Been following this story closely. Feel so much for the families, grew up going to the Sligo area so used to see R118 all the time and live in the East would see R116 occasionally. I've always been fascinated when I saw either. I also watched Rescue 117 when it was on RTE a few years ago and really was amazed by the work they do. I remember thinking Dara was brilliant for getting so high up in a career that is so male dominated. I'm sure she probably inspired girls around the country that if they want to job that is usually done by men they will able to get there if they really want.

I have very limited knowledge of aviation but my understanding of the report was that the pilots relied on the instruments and equipment when flying. Which is understandable because I'm sure they would have been only able to see darkness when flying above the ocean. I wonder if the pilots had been supplied with night vision goggles would they have able to see Blockrock sooner ?

No matter what the final reports says, even if it attributed to human error, it will not change my opinion that Dara, Mark, Paul and Ciaran were heroes who did a very dangerous job and saved the lives of so many people over their careers.

kona · 14-04-2017 12:04AM

Irish Steve wrote: »

The article in Wikipedia https://en.wikipedia.org/wiki/Ground_proximity_warning_systemgives a good overview of what GPWS, and the later EGPWS systems do, and how they do it, both Radar Altimeter and GPS information is used to compare against a database of obstacle heights close to the aircraft.

The hole in the Swiss Cheese in this case is that Blackrock was not in the database, so the warning systems couldn't warn them

Yes, but the is terrain below and in front of the aircraft.

The gpws uses different systems and methods to figure out where the aircraft is relative to these.

The rad alts only cover part of this.
Another thing is that rad alts are only accurate and a relatively low altitude. The higher you go the less accurate they are , which is where QNH comes in.

ProfessorPlum · 14-04-2017 12:05AM

Steve wrote: »

This is inaccurate, the automated call is based on radar altimeter, not the navigation system.

Kona is correct. EGPWS warnings 'look ahead' - generated by the aircraft position in relation to the map database. Rad alt generated warnings, as per GPWS, would have been useless in this situation due to the steeply rising terrain of black rock.

homerjay2005 · 14-04-2017 12:05AM

on vincent brown they said earlier "with 100% certainty we can say human error or factors, were not involved".

alchemist33 · 14-04-2017 12:07AM

Irish Steve wrote: »

The article in Wikipedia https://en.wikipedia.org/wiki/Ground_proximity_warning_systemgives a good overview of what GPWS, and the later EGPWS systems do, and how they do it, both Radar Altimeter and GPS information is used to compare against a database of obstacle heights close to the aircraft.

The hole in the Swiss Cheese in this case is that Blackrock was not in the database, so the warning systems couldn't warn them

The Swiss cheese theory refers to a series of unlikely events happening together or in sequence. Surely an accurate database is the most basic component of this system? I havent posted in this thread because of lack of knowledge but I have to say I'm mad as hell tonight.

TomOnBoard · 14-04-2017 12:09AM

selectamatic wrote: »

This is going to the crux of the issue really, as you pointed out the route was supposedly set direct to waypoint BLKMO as part of the approach route taken to blacksod called APBSS.

Capt. Fitzpatrick clearly stated BLKMO was the little island below as they passed over either Carrickduff or Carrickad so if BLKMO in actual fact was not either of these and was indeed blackrock it's pretty likely this discrepancy was a major factor in the accident.

Now if BLKMO isn't in actual fact blackrock and was indeed either carrickduff or Carrickad it'd seem a lack of awareness re: blackrocks proximity played a key role.

These are the only two scenarios that seem possible to me from reading the report

Further to your point, if BLKMO was at either of the two Carricks, at the point where the RA gave an ALTITUDE warning, the FMS would have had to be updated with the next waypoint as BLKMO would have been arrived at. No such additional instruction was given so it clearly suggests that the FMS was still working off the "direct to BLKMO" instruction.

L1011 · 14-04-2017 12:11AM

Simona1986 wrote: »

Interesting that the aaiu themselves use it in the report

Its a cheap/free source of imagery. Doesn't mean its any use for much else. I wouldn't even trust it for navigation outside of cities.

Irish Steve · 14-04-2017 12:13AM

kona wrote: »

Yes, but the is terrain below and in front of the aircraft.

The gpws uses different systems and methods to figure out where the aircraft is relative to these.

The rad alts only cover part of this.
Another thing is that rad alts are only accurate and a relatively low altitude. The higher you go the less accurate they are , which is where QNH comes in.

QNH in this situation is irrelevant. Normal IFR flight only requires a vertical separation of 1000 Ft above the highest obstacle, and Radalt is well able to cope with up to 2000 Ft, above the ground, so if you cross a mountain that is 19,000 Ft high at 20,000 Ft, you will get a radalt reading of 1000 Ft.

In the report, there is a mention in the CVR extracts that there was a slight discrepancy between Radalt and the altimeters, which would have been local pressure variations, and they were well aware of it, and it was very much factored into their considerations.

The EGPWS system works out their postion from GPS, and predicts course direction as well, then looks at the database for any conflicts in the direction of flight, and if the aircraft is below a safe clearance, it will activate appropriate warnings to the crew, both visual and audible. It gets your attention, and is very hard to ignore.

Sterling Archer · 14-04-2017 12:15AM

God that's a very hard read, absolute tragedy, gone so quick, they'd never have seen it coming.
A serious of events that just worked against them.

Fkn aviation

screamer · 14-04-2017 12:15AM

Human error is to blame if the database wasn't maintained correctly. Software is only as good as the data you feed it. I'm also angry those poor guys trusted their lives to instruments and systems that allegedly guided them to their deaths. I hope beyond hope their families can find some solace. It's heartbreaking stuff.

Gaoth Laidir · 14-04-2017 12:15AM

homerjay2005 wrote: »

on vincent brown they said earlier "with 100% certainty we can say human error or factors, were not involved".

Well, apart from whoever designed the 200-ft-altitude approach, putting BLKMO so close to a 282-ft obstacle. Also whoever thought it was a good idea not to check terrain clearances and the EGWPS database.

kona · 14-04-2017 12:16AM

alchemist33 wrote: »

The Swiss cheese theory refers to a series of unlikely events happening together or in sequence. Surely an accurate database is the most basic component of this system? I havent posted in this thread because of lack of knowledge but I have to say I'm mad as hell tonight.

The database that's being referred to is for the gpws, which is different from navigational database.

The database will have been designed with certain specification. Which means it may be accurate of your flying at 500ft because nobody deemed it necessary to include lower obstacles because who would.fly at 200ft at 75knots 8km out.

This accident has a number of contributions and if you removed one of them then most likely the crew wouldn't be lost

rwaldron21 · 14-04-2017 12:18AM

This must have been asked before but I can't find any ref...

I know the light house has 12 sec strobe intervals but even so , wouldn't you spot a lighthouse a head from miles away, out the front window ?

Unless all eyes where on instruments only for a considerable amount of time ?

Irish Steve · 14-04-2017 12:21AM

alchemist33 wrote: »

The Swiss cheese theory refers to a series of unlikely events happening together or in sequence. Surely an accurate database is the most basic component of this system? I havent posted in this thread because of lack of knowledge but I have to say I'm mad as hell tonight.

You are very much not alone in that sentiment, a number of organisations failed the crew of 116 very badly, it is clear that there are some very serious issues to be answered, and the fact that AAIU have issued 2 specific safety recommendations at the interim report stage is an indication of how serious these issues are, they are sufficiently sure of their ground to be prepared to issue these very specific calls now, even though they have a lot of work to do yet.

kona · 14-04-2017 12:22AM

Irish Steve wrote: »

QNH in this situation is irrelevant. Normal IFR flight only requires a vertical separation of 1000 Ft above the highest obstacle, and Radalt is well able to cope with up to 2000 Ft, above the ground, so if you cross a mountain that is 19,000 Ft high at 20,000 Ft, you will get a radalt reading of 1000 Ft.

I don't think you understand what I'm saying.

Rad alts are more inaccurate the higher you go. 2000ft is relatively low.

The reason a rad alt gives you a accurate reading at 20000ft is because the mountain at 19000 ft is only 1000ft below.

Sterling Archer · 14-04-2017 12:22AM

rwaldron21 wrote: »

This must have been asked before but I can't find any ref...

I know the light house has 12 sec strobe intervals but even so , wouldn't you spot a lighthouse a head from miles away, out the front window ?

Unless all eyes where on instruments only for a considerable amount of time ?

A combination of the weather, there altitude, there speed, the lighthouse elevation and the interval

Gaoth Laidir · 14-04-2017 12:23AM

Irish Steve wrote: »

In the report, there is a mention in the CVR extracts that there was a slight discrepancy between Radalt and the altimeters, which would have been local pressure variations, and they were well aware of it, and it was very much factored into their considerations.

With QNH 1025 hPa, 12 hPa above ISA, their pressure altitude at 200 ft radar altitude would have been 12 x 27 = 324 ft. If only they were using this altitude...:(

Razor44 · 14-04-2017 12:24AM

Having read the report something came to mind. The call out from the rear crew of 'island ahead come right' was met with a call for clarification (correctly), however, when clarified, the avoidance measure taken was to input the direction change into the auto pilot.

Is this not exactly the sort of situation that "children of the magenta line" highlighted?

I don't mean this as a slight upon the crew but more the issue's surrounding automation.

I guess I'm just annoyed that it was spotted but it was to late.

One other point, someone mentioned would/could there be legal action regarding the omission of the island from the mapping software. Potentially yes. If it was reported and flaged as an issue. Who would be liable is pure speculation not worth entering into. But to rule out a civil action is unfortunately misguided.

Rescue 116 Crash at Blackrock, Co Mayo(Mod note in post 1)

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