"What's the worst that can happen?" asks Jetti.

My first instinct is to say, "We could die", but I think for a minute and then say "One of us might die."

Very quietly Jetti says "Isn't it time to set off the EPIRB?"

We knew any help would be some time in coming and, as there seemed no prospect of any improvement in the weather, I reluctantly agreed. I ripped off the EPIRB cover (and was slightly startled when the whip antenna sprung out) and fired it off. Immediately it began to flash and beep. Very encouraging! I also activated our DSC VHF radio. We knew that was a forlorn hope though, as it was unlikely that there were any vessels within 20 miles of us.

We were on our 32ft catamaran Eclipse in the middle of the Gulf of Tehuantepec - renowned as the "Bay of Biscay" of the eastern Pacific, having been lying first to a sea anchor and then a-hull for over 18 hours. The wind and sea state had been steadily increasing since dawn. I'd just been outside to check on conditions and found to my horror that the wind was now strong enough to distort my face. The wind was screeching and the rig vibrating in a way which I had only experienced once before, when safely moored in a marina in 70 knots of wind. The waves were now up to 30ft, and breaking over us more frequently. The sea was covered with spume and looked like those photos in Heavy Weather Sailing that give one nightmares.

Fortunately, despite the atrocious conditions Eclipse was coping well without any help from us, there was no damage and only a little water had got below. However, as we were on a relatively small catamaran, capsizing was a possibility. Although we were warm and dry, we could hardly hear ourselves talk.

A couple of years ago I bought a second hand Iridium phone, primarily for sending emails using the Mailasail service. I also used it occasionally to phone home at birthdays and Christmas but now it was to prove its worth, for I used it to phone Pip Patterson in the UK. I knew his number by heart, and he knew the boat - having sailed with me across the Atlantic. Furthermore as an experienced sailor he wouldn't get panicked by a call from a yacht in distress at sea.

When you register your EPIRB and DSC sets you give a contact name in case of emergency. Don't give your, possibly elderly, non-sailing parents. Choose someone who can actually be of help. Most people don't realise that the UK Coastguard also put a huge reliance on their CG66 form, so you should/must fill one out and also keep it updated. Fortunately this is easy to do by going to https://mcanet.mcga.gov.uk/public/cg66/

Pip gave me the UK's Falmouth Coastguard phone number, so I called and explained our predicament. We then phoned Falmouth every hour to give a weather and position update. Pip also immediately started contacting Mexican marinas and harbour masters by email. This meant that while we were still on our rescue ship we were able to start the ball rolling looking for Eclipse.

Some might think "why call for help when there was nothing wrong with the boat?"

We faced two choices. Stay with the boat but risk losing our lives, or get off the boat alive - but maybe lose the boat.

Not a hard choice really.

Next time you drive your car at 70mph put your head out of the sun roof and feel your face distort. Sit at home and imagine a 20ft wave.

It would wash over the top of your house.

Then imagine it happening again a minute later. Then imagine it going on for 15 hours.

When sailing in the USA in 2003 Eclipse was hit by lightning, but it was all over in a flash and I didn't have time to think "will I live or die". I have been in car crashes and have had a few seconds to think "Will I survive?" We had 15 hours of wondering, and that's the real reason we decided to call a mayday. If you haven't been in a similar position, you have no idea what it is like to think that every moment might be your last.

The first rule of survival is that everyone must survive. That's why it's usually a case of "women and children first". In an all male situation it's often "every man for himself" which is a very different attitude.

The exception being when getting into a liferaft as then the strongest and heaviest should get in first. So although I thought I might survive a capsize Jetti, who is older, and a less experienced sailor than me, might not. As Eclipse hadn't been capsized by 70 knot winds and 30 ft seas the conditions to cause one would have to be even worse than we were currently experiencing. We'd lose our Satphone and gps, and, without them to give our rescuers our position, the outlook would be bleak. I was also concerned because neither of us had eaten properly and had already been awake for 30 hours.

We were going to get steadily less able to help ourselves.

We were, however, reluctant to call for help as we knew it meant people would be putting their own lives at risk when rescuing us. On the other hand, why tell people to buy EPIRBs, DSC radios and the like if you're not expected to use them? If you have a fire at home do you try to put it out yourself or call the fire brigade? Haslar and Tilman were adamant that one should never call for help. Wisely Haslar sailed alone, but I wonder what Tilman's crew were thinking when they disappeared without trace?

During our hourly calls to Falmouth it had became clear that several countries were now involved with our rescue, and we were told that the Mexican Navy would be at our position at dawn. Also, more chillingly, we were told that our Mcmurdo EPIRB was no longer transmitting. This was a real surprise to us, as it was still beeping and flashing. I wouldn't buy one again.

So it was our Iridium phone that saved our lives.

Not only that, but had we left it on standby when we left the boat, then Iridium could have "pinged" to locate it, and thus saved Eclipse as well. Go out and buy one.

Incredibly there are some people who want to risk their lives for the sake of others. Thank God.

At 11pm we had a shock when we heard a female voice saying she was flying a US navy helicopter and was 10 miles away. This was the first we knew that the US was involved. As they flew nearer we set off two flares (the first one didn't work) and made visual contact.

US navy helicopters carry two SAR (search and rescue) swimmers, one who goes in the water while the other acts as winch man. Both are fully trained to be either, indeed ours tossed to see who would do which job. The winner wouldn't stay in the safety of the helicopter but would be the one who jumped in. Clearly they relished the thought of performing a real rescue in survival conditions. On our way back to the ship I thought I've never seen two happier and more excited people. We made their day, just as they had made ours.

So our first real look at our rescuers was the sight of a man on the end of a wire, suspended 100ft below the helicopter with arms outstretched looking for all the world like a flying Superman. He was directing the pilot (who can't see straight down) to a suitable position off our lee quarter. The pilot later said she had great difficulty controlling her helicopter as she was flying at 50 knots to stay in position and was also going up and down 20ft to stay above the waves. Even so, we felt that the wind and sea had moderated since earlier in the day.

Ironically we probably were over the worst of the gale, however having called a Mayday we couldn't then back out.

The noise was deafening, we could no longer hear the pilot, even through the cockpit loudspeaker. The swimmers hand signals added to the confusion as we couldn't decide whether he was still directing the helicopter or telling us to jump in the water. Jetti went back inside and called the pilot who replied "We're ready. It's time to get in the water, folks."

So we tied the grab bags to each other, then Jetti calmly inflated her lifejacket, walked down the transom steps and headed towards the swimmer. (To read my thoughts on Grab Bags CLICK HERE) Incidentally, you shouldn't inflate lifejackets until you're actually ready to get in the water, they'll just get in your way as you prepare to abandon ship.

Five minutes later it was my turn. Unlike Jetti, I am a dinghy sailor, used to swimming in rough water, so I wasn't put off by waves breaking over my face. Instead, I found that the hardest part of the rescue was actually getting into the helicopter. It was a real struggle, probably because we were flying at 50 knots just to stay still - so the wind was blowing us backwards, and thus the winch was pulling the lifting strop at an unfair angle. We lost one bag (unfortunately containing our log books and diaries) when it caught in the helicopter door.

Once seated we were startled when the winchman pulled out a long knife and moved towards us. Without giving us time to protest he slashed both our lifejackets. Normal procedure I realised, as he didn't want us trapped inside the helicopter if it were to ditch. But he could have let us deflate them ourselves!

Half an hour later we landed on USS Ford where after a quick debrief, medical check, shower and meal we were able to get some much needed rest. Thirty six hours later USS Ford berthed in Guatemala.

Aftermath

Despite all that happened, I was very impressed with the seaworthiness of Eclipse. The boat had survived a major storm with no real damage and without capsizing.

The crew on USS Ford were fantastic. Saving our lives wasn't enough, they also looked after us like royalty. So too did Colin Gracey of the British Embassy in Guatemala. He met us off the ship and drove us 80 miles back to the Embassy, where we phoned home. He even recommended a good hotel and later helped ordains the search for Eclipse.

On my return to the UK I visited the Falmouth Coastguard Station who had coordinated our rescue. It was a real eye-opener. The days of Coastguards standing with a telescope to their eye are long gone! The UK Coastguard seem to the ones whom the rest of Europe look to when disaster strikes, when they act as rescue co-ordinators using a very sophisticated computer management system. During my visit they were helping a medical evacuation in the Western Approaches and a 406 EPIRB alert in the USA.

We also visited the San Francisco Coastguard station which had helped liaise with USS Ford.

The big disappointment was the Mcmurdo EPIRB.

Neither USS Ford nor its helicopter received any signal - even when the EPIRB was actually in the helicopter. Back in the UK I checked with Kinloss and learnt that the EPIRB only transmitted a brief signal. Sadly Mcmurdo weren't as dismayed and apologetic as I'd have expected.