Day two was a little more eventful than I thought it was going to be.
We (my training buddy Natasha and I ) started off by swimming two hundred meters in the pool and then floating for 10 minutes to show we could.
Then it was time to suit up. Gear up and make our way once more to the sea pool. Trailing like two ungainly ducklings behind our instructor.
As this was open water dive 3 (my fourth dive) I knew the dive plan fairly well.
Swim out descending slowly to 60 feet / 18meters swim about look at the reef, carry out a couple of drills swim back, carry out our safety stop at 5meters swim the remaining 2-3 hundred meters under water into the sea pool. Surface with 500psi in our tanks. About 40 minutes all told.
I had done the same drill three times before so I was quietly confident.
We carried out our final kit checks. A giant step into the sea. Emptied our BCDs and sank 2m to the sea floor and set off.
We slowly descended following the bottom between to coral banks, so we we were swimming in a valley. Deeper and deeper until we reached 60feet / 18meters. At this depth the colour shifts, less red and everything is bluer or greyer. But none the less stunning for it. We saw large barracuda, lobster, jacks, corals of a hundred different varieties and fish and fish and fish. We saw sting rays and chub and angle fish. We floated in a strange blue alien world. Looking up you could see the bright surface glittering far above.
Now one of the things you do when diving is check your tank pressure gauge regularly. You learn to estimate what you think you have in your tank first, then check. You very quickly get a sense for how fast you use air and can fairly accurately estimate what you expect to see. I had been near spot on with my estimates every time. You are really highly motivated to learn how to do this. I mean basically you have a tank of pressurised gas strapped to your back and it is fairly crucial to the main objective of the sport,’not drowning’.
There we were deep down and I looked at my gauge and was very surprised to see it was showing just under 1000psi, a third of a tank. I had been expecting to see 1500psi. 950pdi was not enough to swim back the half a mile and do our safety stop as planned, and certainly not enough to surface with 500psi in my tank.
I caught my instructors attention and using hand signals I told her how much air I had left, she checked my gauge herself and shot off like a bullet. The normally sedate pace gone.
I watched her go and thought, ‘that’s not going to help’.
My buddy and I followed, Natasha blissfully unaware there was an issue.
Swimming fast at depth uses up air really quickly and would have made a bad situation worse.
So trying my hardest to stay calm I headed back at a slower pace. Forcing myself to breathe slowly and calmly. It was not easy but I fought the rising panic and settled on really a bit stressed.
My instructor ahead of me slowed down, calmed down, I think, and waited until I caught up.
We carried on, more slowly, until we reached our planned safety stop point. A line up to a buoy about 200m from the shore.
I signalled to my instructor I had under 500psi. Her eyes behind her mask went wide and she pulled out her ‘octopus’ the second regulator attached to her tank and passed it to me. I ditched my own.
Now I was breathing on her air.
Then she signals, ‘take off your mask’.
I signalled back ‘what?’.
‘Take off your mask’ she signals again.
So I did, I put it back on emptied of water and she nods.
I knew we were going to do this drill at some point on day two but while I was on her tank I thought ‘odd choice’.
She signalled up and we headed for the surface. I manually inflated by BCD and we floated there.
Natasha surfaced a few seconds behind us.
‘Where did all your air go?’ Came the question from the rather stunned instructor.
‘Dunno’, says I, ‘but I knew we had a problem, when I fist signalled you. I knew I did not have enough air to swim back under the surface’.
At this point Natasha twigged what had happened and just floated there rather surprised and a bit shocked.
By swimming up the slopping bottom to the 5m mark we had been decompressing so at the line we could make it more or less safely to the surface but the fact that the final ascent had been a buddy ascent on her tank meant we had been close to the limit!
There are two risks to balance ascend too fast and you are in danger of getting the bends, decompression sickness. Ascend too slowly you drown…
‘Well’, says the instructor, ‘you stayed calm and did not panic, good!’
We rolled onto our backs and paddled back to the sea pool and our planned exit point chatting as we went. All a little shaken.
We had been down for 43 minutes when we surfaced. Now this is interesting because my previous dives had been 42 minutes, 45 minutes and 43 minutes and I surfaced each time at the shore exit point with about 500psi left in my tank.
So while the dive was about the same Time I was about 1/4 tank shorter on air than the earlier dives…
Well it may have been a slow leak.
It may have been the fact we were down at sixty feet, the deeper you are the denser the air and the quicker you use it.
I may have been working harder than I thought, probably a sign I had not quiet got my buoyancy right.
It may have been the bottle was not really full at the surface a warm bottle (one left in the sun) can give you a false reading on your gauge.
It may have been all of the above.
One thing is certain our instructor had ‘turned the dive’ headed home later than on previous dives and this was one contributing factor. By staying out longer and at depth longer I had used more air.
But it was certainly was not helped by the fact that when I realised that I had an issue I tensed up and when you do that you breathe more air and use your tank quicker!
Either way it was a wake up call.
Dive four went exactly according to plan, the same profile as dive three, same route but this time after 42 minutes we surfaced at the shore with 500psi in my tank.
Our instructor congratulated us both we had passed!
She was happy to sign us off as certified open water divers!
And thanks to the events of the day I had my first real dive adventure story to tell already!
Under an Endless Sky 