Average Reviews:
(More customer reviews)First of all - Yes I own a bladefish. I have tried it in a pool, I have tried it snorkeling in the ocean, and I have tried it in full scuba gear at 100' down.
Pros : Compact, light, portable, great for snorkeling, uses lithium batteries, near zero maintenance (just need to lube a couple of o-rings), good battery life, and quick charging.
Cons: although a great snorkeling accessory - this scooter is an underpowered recreational scuba scooter. You find yourself constantly wanting to fin (just like in all the advertisements and demos you see with this thing) just to keep the fish from laughing at you. Yes it will pull you in full scuba gear - very slooooooooowwwwwwwwly and no where near their claims. Your constant desire to fin will negate much of the positive aspects of a scooter - to conserve air and to have fun! Don't get me wrong - I so wanted this to be the awesome amazing magic scooter invention that cures all the woes of the traditional diver propulsion vehicle (DPV).
I am frankly outraged at the bold faced lies that the recreational scooter manufacturers are allowed to use. Those of us just getting into using a scooter and into diving are not often engineers and we trust the manufacturers... well.. at least we kind of do. We are looking for something fun and the claims of 3.75 miles per hour sure sounds fun - If it could actually do it! I'm ashamed to say that bladefish does not have integrity on their side in this claim. COME ON BLADEFISH -How about if I tell everyone what you don't want them to know.
Let's just be real and talk some math shall we? If you understand speed of a scooter in water you have to understand the concept of thrust. There is a direct correlation between the thrust provided by a scooter and the speed of a scooter as shown by all the hard work of those great guys in the TAHOE BENCHMARK where divers work for days to make sure scooters are given a fair shake and tried in real conditions by both tech and recreational trials.(shouldn't the manufacturers be doing this?)
In order for the bladefish to even come remotely close to its claims of 3.75 mph you would have to travel at 330 feet per minute - which would require thrust equivalent to having X over .00065 to the nth root where 2.08 is n. If you do the math to figure out what X (THRUST) is.... that would mean you would need 112.5699 pounds of thrust. (which if you understand - that amount of thrust would probably rip your mask off - and pull your arms so hard you could get injured - you definately wouldn't be trailing behind it feeling the need to kick) Just watch the demo videos - is that what you see?
That large amount of thrust is required because as the speed increases it gets proportionally harder to pull something through a dense liquid at faster speeds. It only takes 70 pounds of thrust to pull a scooter through the water at near 3mph... but it takes an enormous 113 pounds of thrust to pull only .75 miles faster. (which is what the equation basically shows)
Currently there is only one scooter I know of that comes close to the 3mph mark and has the stats to back it up. That would be the Silent Submersion Magnus which retails for over six thousand dollars and puts out 70 pounds of thrust and 1000 watts! (and weights 4-5 times more because of the large lithium ion battery needed to power such an engine!) Other scooters in that category are the x-dive series of scooters which also sport impressive speeds of over 260 feet per minute. (yet none of them make the false claim of 330 feet per minute!)
Remember the bladefish only puts out 240 watts, and very little thrust. Even if you were a keebler elf shaped torpedo you would have a hard time breaking 1mph. Don't be fooled by some video of people kicking with it. This is a snorkeling accessory or a suped up pool toy that I wouldn't let my kids play with. (do you let them play with a circulating fan at home?) In all honesty it is not as dangerous as a circulating fan because you need both hands to turn it on. (Which is only one more negative thing for scuba)
IF you don't believe me -or the math - then just try it. You will be using amazon's return policy as soon as you can get your scuba gear off. There is no denying the math. I would love to see any bladefish representative explain how they got that figure for speed. Don't be fooled - it does not go 3.75 miles per hour unless it is towed by a boat.
My hats off for pushing the envelope of design, for pushing the industry to lithium ion batteries, and for making the first truly portable scooter. I know in the future you will design one that is made with scuba in mind and the power to back it up. The bottom line is if you're a snorkeler or a rapid diver - this is a great tool. Scuba divers should probably move on to something more powerful.
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