Baker's Article on deep stops aims to clear up some of the nonsense that was flying about around the subject. some divers were using deep stops as a mechanism for avoiding DCS, rather than doing "proper" decompression.
Baker explains why the deep stops are effective, and how they can best be included as part of a decompression plan
Clearing up the Confusion about deep stops.
Another Classic and a a great Read. Richard Pyles Article on the importance of introducing deep stops into the ascent
The Importance of Deep Stops
This is a superb article. A little dated, it hails the beginning of the new era of deep diving using exciting new gas mixtures such as trimix. However, it provides a very good analysis of what happens to a diver as they descend deeper, explains Oxygen Toxicity, and gives divers interested in decompression theory a solid grounding
The Depth and Gas Dilemma
a term often bandied around, the Oxygen window. An excellent article by Johnny Brian, MD
Gas Exchange, Partial Pressure and the Oxygen Window
A scary one this. What happens to your body when you undergo a hyperoxic seizure.
The Mechanics of Hyperoxic Siezures
An excellent introduction to the concepts in decompression theory, by Bruce Wienke.
Bruce Wienke's Excellent Paper on Decompression theory
A classic Article you can probably find anywhere, and most people have read, but it is excellent. Erik Baker's paper on M values, which is crucial to the understanding of traditional models of decompression
Eric Baker Explains the concept of M Values
Ovewr at TeamFoxturd Central, we like simple things. Take howard, for example.
Moving on, here is a simple and accessible explanation of how bubbles work, and how the ascent rate of a dive can affect their behaviour.
bubble Mechanics
Whilst traditional Haldanian models of decompression are simple enough to get your head round, the maths involved in more modern bubble models is mind boggling. here, then is a simple guide for those of us that want the information without the pain
VPM for dummies
A hot topic this one, here is an excellent article on PFOS by Bernhard Meier, MD; James E. Lock, MD.
the mechanics of a PFO are explained, as well as the potential treatments, and links to plenty of other articles about the subject
PFO Article
Over the Stoney weekend recently I was fortunate to dive every serious make of Underwater Scooter including Magnum Gavin, Short Bodied Gavin SLA, my own Gavin Mini G, Silent Sub and the newest X- Scooter Sierra.
It was a great weekend and we were fortunate to have our friend Rob Dobson who has just taken delivery of two X-Scooter Sierras down. It meant the Garf, Gloc and I were able to scooter dive as a team, me on the Mini G and the guys on the two X's. Garf has always been adamant that he doesn't see the point of scooters. He seemed to have changed his mind somewhat by the end of our dive! It was a great end to what had been a hard week, and I have to say that it was the X- Scooter that impressed and surprised me the most. The Gavin's and the Silent Sub were as serious and dependable as you'd expect - but the little X's were quite a revelation.
When you have a good look over an X Scooter there are lots of clever refinements that make you wonder whether the other guys have been resting on their laurels somewhat. Firstly, the X's have a single piece nose cone with just one twin face and barrel O ring at the motor end. This removes one potential point of failure which all the other suffer from (ie an O ring at the nose cone) and this really is just an issue of manufacturing laziness / economy on the part of the other manufacturers. It a lot cheaper just to use a piece of tube and then put a machined nose on the end rather than manufacturing a one piece item. Lots of other clever refinements are abound: The way the battery pack secures into the nose cone, the weighting pouch system for trimming the scooter out, a floodable brushless motor, the neat webbing strap on the barrel, the ring in the nose for threading the towcord when towing and above all an ergonomically designed handle that actually fits your hand in the plane in which these towcord scooters are designed to be used
Nickel metal hydride batteries reduce the size and weight of the scooter to surprisingly manageable proportions - it really is just like picking up a small stage cylinder which is definitely a big plus when you're wrestling with a load of other heavy technical shit. It also means you can take the scooter on a dive where you'd leave a Gavin behind if you doubted whether the viz would be good enough and then when you got to the bottom of the shot and found it was poor, you could just thread the towcord through the nose ring and clip it to your hip D-ring like a stage and carry on the dive. You certainly wouldn't and couldn't drag something of Gavin proportions around for a whole dive if conditions didn't work out - you'd just thumb the dive.
Downsides? X's now have a throttle shifting pitch control which means you can adjust the speed "on the fly" unlike Gavin's and Subs where you have to come off the throttle and turn the knob in the centre of the prop blades at the back of the scooter. This is great and it adds a lot of convenience, but it seems to be a fairly complicated mechanism and I wonder how reliable it is.?That said - Gavin relays aren't exact renowned for being faultless other. Other Gripes: The motor whilst it seems to provide roughly the same outright speed as a Gavin or Sub - doesn't seem to have quite the grunt. I reckon with a few stages and X would be slowed down quite a lot - but for a no stage or one deco bottle dive it would be fine.
In use the X's are a joy: Incredibly well balanced, quick turning and maneuverable - both Garf and Gloc were looking very relaxed by the end of our dive and you certainly couldn't say the same for me the first time I used my Gavin.
At around £2,000 in a compact Pelican case here in the UK - they're at least £500 cheaper than the other scooters mentioned here and I reckon as a fun and Tech1 level dive scooter - they're pretty perfect. For serious exploration or a dive where you're running thirds - look elsewhere - not least because of the NiMh batteries - the issues surrounding which are well documented elsewhere.
X Scooters - More Fun Than Sex With A Fat Bird! Feel free to use that in your marketing boys - the milk of my human kindness just overfloweth :-)
