Split fins (newer technology) or paddle (traditional) fins. There are raging Internet debates over which is better. Divers from both camps cite data gathered with various methods. Each side has their merits, so I thought I would throw my analysis into the ring.
For the record, what I am comparing are traditional one piece stiff fins versus the newer highly flexable split fins. Traditional fins are pretty low tech and closely resemble the shape of a canoe paddle. Some are more flexible than others, some have vents, some don’t, but they are very similar in design. Split fins however are fairly new on the scene and have some radical design elements that make then very much like natures preferred propulsion method.
Paddle or Blade fins work for a variety of techniques and manoeuvres and are preferred by heavily laden technical divers as well as a large number of recreational divers. The high falutin new fangled split fins are very well marketed and have a growing number of supporters in the dive community. I personally have landed in the traditional fin camp and think that is worth while to tell you how I got there.
My first fins were Mares Quatro’s, which are a regular blade fin, the fin of choice where I happened to be shopping and there weren’t any appreciable differences to the other fins on the market at the time. Years later as I forayed into the diving industry, a ScubaPro rep regaled me with stories of performance and style and I quickly switched to their split fin. At the time anyways these didn’t come with directions so I just put them on and kept on diving. I didn’t really see much of a performance difference but I didn’t experience any draw backs either and hey, I was stylin 🙂
Later on when I got into technical diving and was told about things like helicopter turns and backwards kicks is when I started noticing that I was having difficulty with these more complex manoeuvres. A significant issue with the split fins seems to be the type of stroke used.
I am sure that in laboratory conditions that the force, duration and length of stroke are optimized for the best results. Not saying that the machine is set for super-human strength or anything like that. But it has been noted that split fins require a different fining technique to get their design advantage to work for you. Some divers have reported good results by changing the way they fin (usually to a short rapid stroke). Depending on how long you have been diving this may not be an easy aspect to change and will diminish the design advantage.
In addition, there are several advanced fining techniques that are probably not tested in the lab. I doubt for example that the fin kicking robot (and there actually is a fin kicking robot) does reverse kick or helicopter turns. Some divers have reported difficulty in performing these and other manouvers using split fins.
I have put my ScubaPro twin jets (split fins) to the test. I gave these fins a chance (over 1 year of usage) and came to the following conclusions;
A) The fins actually do work as advertised given the appropriate kicking style.
B) If you want to do advanced manoeuvres you may be out of luck.
C) If you wish to vary your stroke (which extends the amount of work you can do) you may also be out of luck.
My conclusion; split fins can work as advertised if you want to go fast in a straight line. But if you want to stop, turn or back out of a situation you may be forced to use other propulsion methods such as your hands. In the north where the wrecks are pristine and fragile and in the south where the reefs are even more fragile I would not be wanting to use hands to move water or grab a hold of something to assist in manoeuvring.
There are divers out there who claim that they can do all of these fancy moves with their split fins (I have seen one in the flesh). I have even met those who dive both, splits for some diving and blades for other. Diving different gear when it suits you doesn’t really mesh with my phillospphy. For the average diver my experience seems to hold true.
Many may call me out on this article with their own opinions which are just as valid but that’s where I stand (or float) on the split about fins.