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Rough Science 5 Zanzibar: Kathy Sykes' diary: Beneath The Waves

Updated Wednesday, 23rd March 2005

Kathy Sykes's diary about the challenge for the Beneath the Waves programme, part of the fifth BBC/OU TV series Rough Science, based in Zanzibar

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Rough Scientists in boat Copyrighted  image Icon Copyright: Production team Day 1

What a crazy, crazy challenge! Kate must be mad agreeing to do it.

We have to provide her with air to breathe underwater.

I once read a book about early divers & cave divers who, I seem to recall, regularly killed each other by not providing enough air, or creating vacuums so large they sucked people’s innards into the tubes.

Not a pretty thought when it’s Kate’s life we’re considering here.

Jonathan will build the pump - and me the air reservoir, with safety mechanisms.

Getting such a huge volume of air for the reservoir to sink will be hard work - and need lots of lead.

So I attached the beer barrel to a big metal tub - so we could have maximum air volume for Kate (I would have put lead into the reservoir direct - but we’d lose space for the air then).

I made a valve to let the air get to Kate - but not water - basically a float that blocked the tube as the water level rises. The theory of it all makes sense - but I’m glad it’s not me doing the breathing.

Ellen and Mike had a day of madness, schleping a bath to the beach for an Archimedes test for Kathy then slinging a balance from a palm to weigh her.

Looked fun, ridiculous - and surreal!

Really enjoyed the day.

Boat Copyrighted  image Icon Copyright: Production team


Day 2

Effectively - had to finish the challenge today because tomorrow we leave early to do the test.

It’s been quite an issue with this whole series … what’s meant to be a three day challenge becomes a one or two day challenge ‘cos we have to travel so long to get to the place to do the test.

It’s been really hard work. An amazing time - but we’re all completely exhausted. All the time.

So, today I just had to make a gauge to see how much air Kate has left in the tank. Quite an important thing!

It’s such a simple design it’s untrue. But so hard to explain in words.

Began the day slowly. Needed to wait for a camera crew to be free. Wanted to get on, but needed bits to be filmed before continuing. So the morning felt really unproductive.

That meant that in the afternoon - I had to get the gauge done - to measure the amount of air Kate has left - it seemed such an easy task - that took all afternoon to complete.

We needed to do a test with Jonathan’s pump, my reservoir, my valve to keep water out of Kate’s demand valve and my gauge. Ended up hugely stressful - racing the clock, testing it all in a water tank with last minute discussions, changes and tweakings.

By the time we were ready - it was six and the light was fading. Much more tense and stressed than it should have been. It always gets a bit crazy when we’re trying to ‘marry’ different bits of kit late in the day. Too many people with too many different ideas with no time to change things.

But it worked! The pump worked - the reservoir sank, it was possible to breathe, and when there was no air - Kate didn’t breathe water.


But - the water was too shallow to test the gauge. A real shame - it would have been nice to know it worked BEFORE going into the sea!

Rough Scientists on boat Copyrighted  image Icon Copyright: Production team


Day 3

Pretty nerve-wracking night. Spent the last two nights dreaming about trying to keep things airtight underwater, so someone could breathe. I wish these challenges didn’t get to me quite so intensely!

So began the day tired. It was a grim, cool, cloudy, early morning. We had to cross the island on a really bad, bumpy dirt road to get to the place that had been chosen.

It began chucking it down on the journey, and the wind was whipping up. The last thing we needed was big waves, rain and bad visibility underwater.

Everyone seemed tired, stressed and a bit quiet.

There was the usual -shenanigan about boats - who to go where; how to get on safely; where does the food go - lots of logistical messing about. Necessary - but dull.

Even once on the boats, everyone seemed quite low. Usually, being on the boat is so nice, we all perk up. The rain and wind didn’t help I guess.

We crossed a hugely wavy bit of ocean - with the biggest waves we’d yet seen. I think we were all wondering if we’d need to return tomorrow to try again in more reasonable conditions.

… But gradually the sun came out. We reached the island, and in its shadow the waves were tamed. It was like being transported suddenly to a different place.

I was the first to get in the water once we’d sunk the air reservoir. I had to sort out the air gauge. It was simply a float (an empty plastic water bottle) inside the air reservoir, tied to a bit of rope that went through one of the holes at the base, then up to a wooden pole. The wooden pole would be pulled down when the float went up. So an empty tank (empty of air, but full of water) would be indicated by the pole being at its lowest point. When the reservoir was full of air (and empty of water) – the float would be at the bottom of the tank, allowing the pole to be at its highest point.

To detect the movement of the pole, I needed a reference ‘stick’. … so this was just a wooden bar tied with a rope to the top of the reservoir.

Sounds easy - but it was a lot of noncing around underwater, tying knots, cutting ropes, adjusting floats and untangling rope and string … while everyone else waited.

The joy of it was - once working - it was so clear what the air situation was like. Not even I had fully appreciated what a key thing this was (and I built the thing!). Essentially - it was our only way of knowing whether Kate would get her next breath.

So - Jonathan and Ellen pumped. I assessed air level, Mike made sure the tubes didn’t get tangled or twisted.

Kate took some breaths at the surface - then went in.

We were all pretty tense. She told us to pay attention and keep pumping … and off she went.

It was a joy to see her underwater. She looked so comfortable! The weights were perfect - she hung just above the bottom perfectly. Then she swam off to the reef, literally swimming ‘til the end of the tube was taut, the end of her ‘leash’.

We were over the moon! And it was easy to forget to pump - it was all so exciting. But the gauge would get close to the bottom I’d yelp ‘get pumping’ - & the air level would creep back up. What an amazing challenge!





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