I can really feel for the families of the four on Cheeki Rafiki, I know the gut wrenching feeling when a friend or former crew mate disappears at sea.
It is natural to cling on to hope … and yes there is a chance that they are still alive … but it is remote.
Having had two of my friends and former sailing mates lost at sea in separate incidents, I know how it feels, and can sympathise, however, I do think the attempts to coerce the USA Coastguard into extending it's search a thousand miles offshore was misplaced.
Sailing is dangerous and everyone who takes to the Sea is aware of the risks.
Several factors make me believe that Cheeki Rafiki lost her keel, resulting in an immediate capsize. There were probably two members of the crew on deck on watch, not wearing their life jackets or fastened to the yacht with safety harnesses (I would not expect experienced sailors to clipped on unless conditions were extremely severe or they were doing something on deck that had risk). Being a racing yacht the Life Raft would have been stowed below deck together with the yacht's EPIRB. The two personal EPIRBs that were activated were probably from the two members who were down below and would have put on life jackets before attempting to escape through the now below water companionway. Deployment of the Life Raft amidst the chaos of the capsize would have been well nigh impossible and if they did manage, they did so without the EPIRB, which would have been separately stowed near the Life Raft.
Cheeki Rafiki is not the first yacht to loose her keel, nor will she be the last. Here is a link to the report on Moquini a yacht on which Neil Tocknell, a close friend and sailing companion, lost his life in similar circumstances during a Mauritius to Durban Yacht Race in 2005.
The report that Cheeki Rafiki had been taking water but the crew were in control is very reminiscent of my own experience in my own yacht Swimlion, also during a Mauritius to Durban Yacht race. We began taking a cup or two of water a day in the vicinity of the keel bolts, at first we assumed one of the keelbolts had not been fully torqued, but once one of the crew noticed that the hull was actually flexing alarm bells started ringing. For 12 hours we stopped racing sailing as gently as possible eventually after a full crew discussion we moved the Life Raft, EPIRB and grab bag with extra rations into the cockpit, and resumed racing … the only difference we allowed only one crew at a time down below for rest, knowing that if the keel fell off the boat would capsize and getting out from down below would be difficult. Discussion with the designer after the race showed that the builder and project manager had misinterpreted the the design and effectively only built that area to less than half the design rigitity.