I was working as an instructor for a dive shop, the owner wanted to promote deep and decompression stop diving so I was invited along for free to allow interested divers to view my kit of doubles with lean and rich staged decompression sling cylinders. This was a while ago before technical diving had been established in Perth dive centres, they had done some deep dives before and wanted my feedback.

Pre-dive, much to the surprise of the divemaster, I handed in my written plan on my own worksheet that included depths, planned stops, full gas consumption, CNS, OTUs and contingency plans of 3 metres too deep, 5 minutes over time broken down into minutes at each depth and runtime.These guys were strapping computers on, getting into deco with single cylinders and standard regulator set-up and of course, no training.

My dive was solo, I had 20 minutes at 40 metres with air as the bottom mix, EAN36 as a travel mix from 30 metres onwards, decompressing on EAN80 on the bottom mix table, not accelerated as the hang time wasn’t excessive as I wanted to practice skills during the hang including deploying my lift bag at 6 metres for the shallow stops.

I was to be first in the water as I had a) the longest runtime, b) the only proper plan, c) full extended range kit and d) they just wanted to get me out of the way with all my equipment. The skipper had put us out on a reef not to far from Horseshoe Reef on the North West side of Rottnest Island. A highly noticeable surface chop was running, not ideal surface conditions and a strong current running. The 15 metre dive boat was moored on anchor in 40 metres on a rope line, this was a square profile.

Amazing, not only was there no tension on the anchor rope, we had a loop in it as the wave chop was pushing us in one direction on the surface and the current was pushing the other direction cancelling out any movement. I hit the water with a negative entry deciding to do my s-drills below the surface making my way immediately to the anchor line.

My bottom time was uneventful, I made it back to the anchorline with 2 minutes to spare (18 minutes runtime) and pottered around before starting my ascent. As I came off the reef, I didn’t want to be too close to the ascent line as I wanted to practise a bluewater ascent, I was immediately swept away from the line with the current. I had been too lax and had to swim at maximum exertion to get onto the line whilst changing to EAN36 as per my plan at 30 metres.

I did make it to the line about halfway through my ascent, man was that a workout, lesson learned, extra resistance in the water with doubles and two stages and a decompression obligation. The rest of the dive was uneventful, switched to EAN80 at 9 metres and hung on tightly to the ascent line while feeling the sensation of being towed through the water. I never encountered an other divers during my ascent, I never noticed as I was concentrating on what I was doing after getting myself into a little bother. Upon surfacing, I climbed back onto the boat, I was the only diver to make it back to the boat at this stage, this was unusual as my total runtime was xx minutes and longer than anyone else on the dive.