Murree to 51.4 m/157 ft

The Murree lies in 45-70 m (137-213 ft) in the middle of the English Channel, so we knew this would be a deep dive. Mac and I planned to go to 50 m (152 ft) and leave the bottom after 15 minutes. Also if either of us got down to 120 bar (1718 psi) we would return to the shot line regardless. If we didn't find the shot line by the time either of us got to 100 bar (1431 psi) we would deploy a delayed SMB and decompress on that.

We hared down the shot line and got to the wreck in about 45 m (137 ft). It was still fairly light down there, but the vis was very disappointing because of huge chunks of plankton doing a very good imitation of a snow storm. I could see railings, but apart from that could barely recognise anything I saw as being part of a ship. We swam through the railings and I shone my torch on some fishing line signalling to Mac to look out for it. We dropped down until we noticed that we had reached close to 50 m (152 ft). We swam down into a little hole so that we could break our previous depth records by a tiny amount. We then swam up and along more rusting wreck.

For a recent wreck there was plenty of life already taking hold. Everywhere we shone our torches the ship was plastered with Plumose anemones and dead man's fingers. As we swam along some more railings I noticed I had reached 110 bar (1575 psi). I signalled to Mac and we ascended in search of the shot line. On the way we passed Tony Fentham with his distinctive yellow twin set. We got to the very top of the wreck and realised we weren't going to find the shot line in the gloom. I got Mac's delayed SMB and reel out of his stab jacket. He readied it and I used my octopus to fill it. It took a while to get going, and by the time it shot up to the surface I had gone down to 70 bar (1002 psi). Normally this wouldn't have been a problem, but for a deep dive this wasn't ideal. Lesson learned: use air sparingly when filling a delayed SMB; ensure air is going in by feeling with your fingers instead of just blasting away your air and hoping for the best.

We rapidly ascended to 20 m (61 ft). We were comfortably within BSAC's maximum ascent rate of 15 m (46 ft) per minute, but fast enough to cause our computers to flash 'Slow'. We paused at 20 m (61 ft) for a minute or so and then proceeded genteely to 9 m (27 ft). My computer showed an elapsed time of 21 minutes - bang on plan. We stayed at 9 m (27 ft) for a couple of minutes and then sedately rose to about 6 m (18 ft) where we spent the rest of the dive decompressing.

After 40 minutes total time our computers still hadn't cleared. We kept on hearing what sounded like oil tankers bearing down on us. We looked at each other as if to say "Gulp!". We could have ended the dive there and then having conducted it comfortably within the BSAC 88 tables. I was down to well below 50 bar (716 psi). Added to this the fact that we were in the middle of the English Channel in one of the busiest shipping lanes in the world, and we came to the conclusion that we should surface. This was the last dive of the holiday, and if our computers were a bit sulky it wouldn't matter.

This was my deepest dive to date, and although not particularly memorable in any other respect (the vis was terrible) I learnt a lot. We planned the dive well and stuck to the plan. I learnt not to waste air when filling a delayed SMB, and that it takes longer than you think to deploy one if you can't find the shot line to return to the surface. The only niggle was that although we had planned and conducted the dive well within the limits of the BSAC 88 tables, we had missed a couple of minutes of a stop at 3 m (9 ft) according to our ultra- conservative dive computers. Next time I dive this deep I'll take a pony bottle with me. However all in all this was a very satisfying dive.