Originally Posted by
gulliBell
Isn't the light beam columnated? The light wouldn't go up into the cloud, it's angled down towards the surface. And at one flash every 12 seconds, they might not have been below cloud for long enough before hitting the rock for the light to be visible to them. But yes, from 500' up even if you were in cloud, you'd expect to see the light, or the clouds light up around you, every 12 seconds from a few miles out.
The co-pilot did have a target on radar, he reported "target at 6 miles 11 o'clock Large" and the pilot replied "just a small little island, that's BLMO itself". This call came 15 seconds after the co-pilot reported 1.3 miles to BLKMO. This I just don't understand, it's evidence of a breakdown in SA. I mean, when you've just been told BLKMO is 1.3 miles in front of you (according to GPS), and there is a radar target 6 miles ahead of you, how could that radar target possibly be BKLMO? What that target probably was is Duvillaun More, which you'd expect to be at 11 o-clock on radar because the next segment takes you to the right of it. And the co-pilot should have identified the radar target as a possible obstacle on the next segment by looking at the map, and he didn't question the pilot when it should have been obvious that a radar target 6 miles in-front of you couldn't possibly be a GPS waypoint only 1 mile in-front of you. And another thing I don't understand, when the co-pilot reported 1.3 miles to BLKMO, there MUST have been a big red target directly in front of him on the radar (assuming the radar was set to 10nm arc and 1.3nm is still in the detectable range). Also, the crewman told the pilot the island was visible directly ahead 15 seconds before impact, and to come right. In the 6 seconds before hitting the rock the FDR shows they were not making any heading change to ensure lateral separation.
From 200' above the surface and at 3nm range, a 300' island in-front of you would probably indicate on the radar screen as an obvious red blob with little depth, probably with no other colours evident, probably with some sea clutter either side of it, with a great big arc of black for miles and miles behind it. And as you got closer to the target the red blob would be getting bigger and bigger, and the black arc behind it would stay just as black. That great big arc of black behind a red radar return should attract your attention, because that black area with no radar returns is potentially dangerous. It's dangerous of course because a big island in-front of you has bounced all the radar energy back to you, and nothing behind it can be detected. If it was only a small island with little elevation the radar image would be completely different, you should see sea clutter returns only a short distance behind the red return. I've got a hunch the radar was painting a good picture of what was in-front of them for the last 6nm, but there was no proper interpretation of what the radar was telling them.
I know it's easy to be critical from armchair comfort with the benefit of time and hind-sight and the rest of it, but the brutal reality of it is, I don't see much PIC stuff going on. The pilot said virtually nothing of substance through the whole of the end of CVR transcript, when the aircraft was getting in an imminent state of peril. And the bit the pilot did say about BLKMO was obviously wrong but it wasn't corrected by the co-pilot. Blackrock must have been detectable on the radar directly in-front of the aircraft for the whole of the track inbound to BKLMO, and it should have been identified and reported as a hazard to the pilot, but it wasn't. The warning from the rear crew about the rock in-front of them either wasn't made forcefully enough, or wasn't acted on quickly enough (no avoiding action was being taken in the 6 seconds before impact). My reading of that little bit of CVR transcript is not enough of substance was being said amongst the crew. My flight instructor used to say "silence is bad CRM" - for me, and again this is being said from the comfort of my armchair, there is just too much silence on that CVR transcript.
To add to my last...
There would be no red blob, they were in GMap which gives gives a blue/green/purple palette with less contrast. Pedantic, perhaps, but I am highlighting that so much of the comments are based on a basis of knowledge and experience not directly related to this incident.
Yes, the radar should have been painting a return but I am reminded that radar does not paint vertically. A shoal and a cliff can appear the same and we can easily see what we expect to see...
I do agree that they weren't saying much. 2:46 was the first indication of the island, calmly reported and responded to. But until 10 seconds later, 2 seconds before impact it looks like a typical sterile cockpit in minimum weather.
Most appear not to have actually read the report (not you GulliBell).
The proximate and fatal error was that the crew were unaware the waypoint was also an island. Most of the rest of the errors follow from that clearly flawed mental model of the route.
In the report, it is an assumption that the camera was how the island was seen, not confirmed fact...
And I won't bother to repeat the observations I made previously about my own experience with these routes (not procedures).
I do recognize that the UK seems to have a different practice with regard to IMC letdowns to off airport locations and I don't know if similar practice applies to Ireland. Where I have flown, I would not expect a useful IAP to Blacksod to be approved by the CAA.