what terrible irony....RIP all the crew.
Julie that is an argument based on 20/20 hindsight - there is significant risk to the rescue crew going out to the fishing vessel since they are out there by themselves with often patchy comms. In order to mitigate some of that risk, top cover provides comms relay and, in the case of it being provided by another SAR helicopter, a means of rescuing the rescuers or completing the rescue in the event of failure of systems on the primary rescue aircraft.
Therefore, it is highly efficient to utilise a second SAR aircraft for top-cover on a long -range job in the Atlantic.
The primary rescue isn't complete until the casualties are safe back on land and there are many things that can go wrong during that process. The aircraft can develop a fault requiring turnback, the conditions on scene can be so bad that the rescue just isn't possible or the aircraft reaches its time on scene and has to depart in order to make land, the winch could be damaged delivering the winchman or the winchman could be injured in the process of getting on the deck. For all of those reasons and many more - top cover by a SAR helo is very desireable and , as part of the overall mission, operating to the same limits and procedures (all trained for) is more than appropriate.
Thanks for the enhanced explanation. This debate is not a 20:20 hindsight one since we don't know why the accident happened, and as far as I'm concerned we are talking generalisations.
With the advent of satellite phones, surely the Comms thing isn't much of an issue these days? If top cover is provided by FW, most of your remaining points aren't relevant. If provided by SAR heli then they do mostly seem to be "nice to have"s. How often does a heli have to rtb mid-mission due to a technical issue? If time on scene exceeds endurance then surely this also applies to the top cover heli? The case for taking the enhanced risk with the second crews lives doesn't immediately seem easily justified to me, unless there are actual statistics showing the need, which I somehow doubt.
It is all a matter of opinion and acceptable level of risk, but I wonder if anyone considers just how necessary a second heli is vs the risk when tasking, or whether they just do what they have always done because that's how it's always been done.