Jet Fin vs Rocket Fin

[Sam Miller III]

A post on the same general subject from long ago. This should supply some of the answers to some of the buring questions...

<<Nem "Ya all gona be at Portage Quarry in August?" looking forward to seeing you again>>>

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The Jets first appeared on the American scene in the JYC movie "World with out sun"

The were rejected by US Divers in favor of the ill fated and very short lived "Caravelle."

A very new struggling company called Scuba Pro imported the Jets from France..where they were designed. Jets were an immediate success on the American market by the beginner and novice divers of the era.

US Divers introduced the Rockets a stiff fin with a slot in the blade; a copy of the Jets. They were produced in Santa Ana plant. Arnie Broshinki was in charge of molding..In 1976 were made in Red, White and Blue and several pairs were made for selected divers with red, white and blue flames -ala a hot rod flames.

Other long forgotten companies followed suit with fins with fins with slots--ie Sportsways with the 707 etc

Scuba Pro obtained the rights and molded Jets in their Compton, California facility under the late Karl Kaiser, who later established IDI.

The Jets had a patentable feature; the overlapping surfaces referred to as a thrust acceleration feature; all the other copies had holes in the fins.

I952 Captain Walt Mazzone perform the fist fin test for USN --the recently introduced Ducks designed by Laguna Beach Diver Al "Brownie" Brown were superior. Walt is still kicking!!!

1955 the late LA Co Instructor Bill Barada did a fin test- the Ducks were in every way superior

Dr. Tony Christensen performed very extensive fin performance test at UCLA. Best fin was Duck Foot, followed by a US Diver Aqua Lung, then Jets and some were down the line Rockets.

Several years later, Son Dr Sam IV performed a series of fin test with out the stiff blade Ducks & Aqua lung, the best over all was the Plana, followed by the Jets and down the line the Rockets.

The best over all fin was the very early gum rubber Duck Foot made by Spearfisherman of Laguna Beach, then the Swimaster Voit models, followed by the early Planas, Jets and way down was the Rockets.

Ten years ago I published a rather extensive three part article in Historical Diver called "A short history of Fins" Tracing fin development from long forgotten Havlor Olsen to De Courlier (S) to Churchhill to many long forgotten but keystone designs of the 1930- to 1990s.

I would, for divers of today, consider the Jets the best performing fin on the market.

Dr. Sam, 111

Cheers from a hot CenCal,

sdm

 

[Blue Sparkle]

Anyone want to buy a pair of Rockets?

 

[SurDo2]

I like Rockets more than Jets... That being said, I thinks they swim almost the same.

But that's just me.

 

[Nemrod]

James, I completely agree with you that the Jets are much, much better than the Rockets.

However, to be fair, you really need to show the flex of a standard Jet compared to the standard Rocket. Of course the longer SuperJet will flex more, just by virtue of it's length. Not fair. That said, I know the Jet would still win!

Also, you had me going to double check mine. What made you say the jet ports on the Rocket fins are upside down? The ports on both my Jets and Rockets direct the water the same way- to the rear on the downstroke.

I ought to weigh them. But, still, I think it is fair, 1/3 of a blade is 1/3 of a blade. One is stiff like a board, one has plenty of flex as clearly seen. I could have moved to 50% position with the Jet and it would still flex more than a Rocket held on the tip. Rockets are a very stiff fin, Jets are not stiff at all by comparison.

What I mean by upside down, I did not say what I meant, lol, I mean the curve is wrong, it is backwards or maybe my brain is backwards today. The camber is the lift side, it should be facing the direction of travel.

N

 

[hawksbill]

Thanks Nemrod and Sam Miller for the info and history, this confirms what I have suspected. Most of my dives have been in the XL Jets and I have never been inclined to change in 25 years. Still using the original pair with rubber straps although, I have had to change the straps at least 4 times now. Recently I bought a pair of mares full foot super channel fins for warm water snorkelling and travel as they are much lighter than the Jets but I have not gotten to use them for scuba yet just in the pool and they are nice and light but for my heavy drysuit gear I would want the Jets for sure.

 

[DennisW]

I've tried Rockets just for the heck of it. Never again. I have also tried split fins. They were ok, but fluttered when you kicked hard. To me, that means they are losing the thrust you are trying to achieve, so back to the Jets. Oh yes, Jets are relatively inexpensive when you look at all of the fancy fins out there.

BTW, Jeanie Tagge actually finally wore out her Jets. I don't know how old they were, but she got them when she was in college (I think). She wore a hole in the foot pocket right where her big toe sits.

 

[Walter]

However, to be fair, you really need to show the flex of a standard Jet compared to the standard Rocket. Of course the longer SuperJet will flex more, just by virtue of it's length. Not fair. That said, I know the Jet would still win!

There is no "SuperJet." There are Jet Fins and Lightning Jet Fins. Lightning Jet Fins are all that have been made since the late 70s. Jet Fins without the lightning bolt are fairly rare these days and both types are usually referred to as Jet Fins.

 

[Sam Miller III]

FYI
Jet fins have a density of 1.03--Same as sea water.

Rockets unknown -but suspect higher density

 

[olkev]

There are Jet Fins and Lightning Jet Fins. Lightning Jet Fins are all that have been made since the late 70s. Jet Fins without the lightning bolt are fairly rare these days and both types are usually referred to as Jet Fins.

Somebody tell me if I am dreaming . . . I thought I saw a thread somewhere, here or some other board, that talked about the difference between the "Lightning Jets" and the "Jets". I can't seem to recall if it was in regard to the compounding of the rubber or what but there was a difference, maybe slight.

Can anybody discuss the difference between the two? Is one really more desirable than the other or is the latest and greatest the same as the original?

 

[Nemrod]

Somebody tell me if I am dreaming . . . I thought I saw a thread somewhere, here or some other board, that talked about the difference between the "Lightning Jets" and the "Jets". I can't seem to recall if it was in regard to the compounding of the rubber or what but there was a difference, maybe slight.

Can anybody discuss the difference between the two? Is one really more desirable than the other or is the latest and greatest the same as the original?

The earlier Jets did not have the lightening bolt insignia, functionally they should be the same or at least very similar. It matters probably only to Vintage Era Equipment Divers who are trying to be period correct.

Sorry Walter, I have always called the XL Jet the Super Jet as I have encountered that term many times during the 70s when I worked in a ScubaPro shop, thank you, to distinguish the fact the the size XL is considerably larger in blade than size L and less. I agree, the term has fallen into disfavor long ago. I imagine it came into usage because the larger foot pocket Rocket was called the "Super" Rocket and like I said, I lost one of those on the Timberholes in about 1974 and I replaced them with Super Jets :kiss2:.

Hawksbill, you have done the same thing as me, I bought my wife some Mares Avanti X3 and we have been so impressed with them that I am getting me some. The reason is they are very light weight, they have a shorter blade that fits well in our "reduced" and downsized travel bag (two divers outfits in one bag). Outfitted with spring straps they are a nice fin. The X3 has been discontinued and replaced by the, uh, I think they call it the "Super" Channel kind of like "Super" Jet.

N