I don't think we can comment on the design of the approach without seeing the accompanying text which is briefly referred to in the report section 3.5.8. The red highlighted numerics on the chart obviously refers to notes in the unseen text describing the significant obstacles, of which Blackrock was included. I would have thought that as part of the approach brief, they would have gone through the accompanying text in some detail. If they had done so, they must have been aware of the presence of a 310' high obstacle on the approach path.
We should also remember that the chart does not describe an IFR cloud break procedure. It seems to be just "route guidance" to aid what should be a visual section of the flight. I suspect that elsewhere in the company Ops manual there would have been an offshore cloud break procedure to get them VMC below cloud. This procedure should also detail the minimum visibility (which is of course almost impossible to determine at night) and cloud base to allow continued visual flight at low level. The limits for a SAR mission may be significantly lower than for "routine" ops but we have to remember that this particular flight was not for a SAR operation. It was just to provide an extra communications link at this stage.
It's easy to be clinically analytical about this subject and forget that humans were involved in this tragedy. I have a huge respect for those who, on a daily basis, put themselves into potentially very hazardous conditions to help protect life. RIP.
Last edited by roundwego; 14th Apr 2017 at 09:57.