To that end in the future we will simply purchase an aircraft that is or has the following:
Reliable and reasonably modern and commercially viable, like what good airlines buy.
Long or very long range from a UK runway.
Has radar and other modern aids to locate people unfortunate enough to be in and at the mercy of the seas.
Be able to communicate and therefore steer other rescuers to the scene.
Possibly drop aid to people in the water.
And fly back to the UK again without crashing, or running out of fuel and crashing.
Well that's SAR covered, but what about all the other requirements?
Thank goodness you aren't in charge of procurement.