Differences between Jets and Rockets?

[SDAnderson]

So what are the differences between jet fins and rocket fins?

How detailed an answer are you looking for? Hard scientific performance data on either is somewhat lacking but there is a ton of annecdotal evidence out there.​

Am I correct that Scubapro's Jets came first and Aqualungs rockets are a somewhat knockoff/clone?

"Which one is better" is a worthy question. "Which one came first" seems like a monkey-see question.
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Is the jet fin popularity more of a monkey see monkey do than a real difference in the fins....

Never underestimate the power of the herd. As with the placebo effect, the power of the herd can become a self-fulfilling prophecy and, as such, the question is mooted. That said, I got my first pair of JetFins in 1971 (and still have them, which also counts for something) and have tried a bunch of different fins (including the Rockets) over the years. In the end, I still come back to the JetFins when I can, though my paddle feet and my drysuit conspire to force me into the larger Turtles for much of my diving. "Best" is a subjective term - determine what characteristics you need in a fin and don't sweat the picayune. If you're like most of us, you'll never stop trying different fins that fit your profile. If you're like many of us, you'll settle in on JetFins.​

 

[John C. Ratliff]

I put a bunch of material on the Vintage Scuba website about the Jet Fin. In response to the questions above, let me say that the Jet Fin did come first, but much earlier than you may think. You can see what I wrote there at:

http://vintagescuba.proboards2.com/index.cgi?board=general&action=display&thread=1133330933&page=4

In a small part of the above entry, I wrote:

It is interesting to note that Cousteau's book, World Without Sun was published in 1964. It documents the Conshelf II project in 1963. Their divers are using Jet Fins exclusively throughout this book, and throughout the movie of the same name. Georges Beuchat, of Marseille, France, filed his original patent on April 25, 1962, and apparently produced the fin in that time frame. His US Patent, #3,183,529 was granted May 18, 1965.

Now, concerning the Rocket fins, I have a pair, but they don't compare with my ScubaPro Lightning Jet Fins, as these Jet Fins are much larger and have a different rubber composition. It is important to note that the current Jet Fins are probably what ScubaPro used to call the "Lightning Jet Fins." The Rocket Fins and the original ScubaPro Jet Fins compare, in my estimation, favorably. The Rocket Fins did not have the patented blade overlay that the Jet Fins enjoyed, and so they simply vented the water through the blade, rather than "jetting" the water in the direction of travel of the diver on the back side of the blade.

The thread mentioned above documents my attempts at fin design, with what I call the "Scoop Fin," which IMHO is still better than either of these mentioned fins.

SeaRat