Difference between force and jets

[JKPAO]

I love my Force fins! (and no I don't work for or rep for FF's) I can even frog kick with mine.
I could give a ship what fin you wear!
When it comes down to it, does what the other guy's fins look like or cost
really concern anyone but the user? I think some are just too ....?
See you topside John

Oh and as far as never wanting to try them, Why?

 

[sibermike7]

no I don't work for or rep for FF's

What???!!
Bob didn't buy you lunch either!?
Come on Bob, you're letting your reps down!!

 

[meesier42]

Did it occur to you that most of the "pros" are company reps and shills? Did you ever wonder why no reputable group or individual who conducts controlled tests on fins has ever rated the force fin as anything other than mediocre? Oh, wait, you are just caught up in the excitement of it all.

Lets see you have just called the following individuals and groups shills and liars, all of whom are highly respected in diving communities, much more so that anything you will ever accomplish.

University of Buffalo
John Chatterton
Jean-Michelle Cousteau and the entire Ocean Future Society
Jonathon Bird
Undercurrent
Fraser Bathgate (VP IAHD)
Hal Watts

hmm... since the ONLY controlled test that included ForceFins ever conducted was performed by U of Buffalo and I am confident that you have never actually read it, I have no idea what you could possibly be basing your conclusions on

BTW- I greatly look forward to the day that Bob sends me paycheck... but until then, I am just a proud supporter of the ForceFin and do my best to provide useful and honest information to the question are asked.

 

[InTheDrink]

How come there's only been one controlled test that included FFs?

 

[meesier42]

because long term and intensive studies cost a lot of money and ForceFin doesn't pay to get them included as other companies have. I spoke with Dr Pendergast at U of Buffalo about 2 years ago, to include a fin into their testing, it would cost not less than $100,000 per design to be tested. The one conclusive study performed by U of Buffalo was in 1991-92, and was sponsored by the US Navy, which is why the results of that study are not widely available, the Navy claims that the information from the study would "likely to cause substantial harm to Force Fins competitors and were determined exempt from disclosure under title 5, United States Code"

The key conclusion from that study said
"The most economical fins were the smaller, very to moderately flexible styles. The larger, less flexible fins were the least economical. The presence of vents did not seem to be an advantage under any condition. It would appear that the smaller, more flexible fins did not compromise neither speed nor force underwater. At the surface, it would appear that the greatest force and least fatigue could be generated by the larger, less flexible fin."

This was echoed again in a follow on study that U of Buff performed a couple of years later, but this study did not include ForceFins. this one can be found on the Rubicon Library
1) "the divers invariably ranked the stiff fins as the best and the flexible fins as the worse, which did not correlate with the objective evaluation of the fins"
2) "the hamstring muscles of men are weaker than the quadriceps, thus the power stroke should generate more thrust than the recovery stroke"
3) "In our work, fin where successive trailing edge segments that progressed to 90degrees to the horizontal produced the most thrust during the power phase"

even though ForceFin was not included in this second study, their conclusions describe a fin that sounds a lot like a ForceFin

conclusion #1 above is one of the reasons that I always ask people to use the fins for at least a couple of dives before making any decisions, its takes a while to overcome the mental training that most other fins generate

 

[tgsmith]

So what kind of magical propulsion technique does John Chatterton use to not stir up silt? Or is this also "classified" and too good to be used by the masses? Any videos or demonstrations someone can point me to?

 

[meesier42]

he used the Extra Force Tan Delta Fin, with a proper kick its very easy not to stir up silt, as the wash from your fin is behind you, not down into the silt, not to mention is easy to frog kick and scull very well in this fins. Watch his History Channel specials "Deep Sea Detectives" to see just what he does

of course you can ask Hal Watts what he does, as he recommended the Original and Pro for caves, as I understand it, he recommended using a high ankle kick, ankle well above your knees and doing short kicks keeping your ankles above your knees, this kept the wash high off the bottom and behind you

 

[4sak3n]

... all of whom are highly respected in diving communities, much more so that anything you will ever accomplish.

University of Buffalo
John Chatterton
Jean-Michelle Cousteau and the entire Ocean Future Society
Jonathon Bird
Undercurrent
Fraser Bathgate (VP IAHD)
Hal Watts

...

 

[jlovold]

he used the Extra Force Tan Delta Fin, with a proper kick its very easy not to stir up silt, as the wash from your fin is behind you, not down into the silt, not to mention is easy to frog kick and scull very well in this fins. Watch his History Channel specials "Deep Sea Detectives" to see just what he does

of course you can ask Hal Watts what he does, as he recommended the Original and Pro for caves, as I understand it, he recommended using a high ankle kick, ankle well above your knees and doing short kicks keeping your ankles above your knees, this kept the wash high off the bottom and behind you

Compared to a Jetfin, the FF Extra does not frog-kick well, unless you modify your kick greatly, as I did, and got pains in my knees instead...

I would really like to test the Excellerating forcefins, because, I like my Jetfins, but they are not perfect.

BTW, after my first dive with the FF Extra, after having dived FF Pro for a few years, a friend of mine asked me how I did like the new fins... I replied that they felt cold...

In other words, I was hardly working underwater, while keeping up with the other divers, compared to the Pro.

 

[InTheDrink]

This is off topic, covered in a thread adjacent to this one and probably has countless threads relating to same or similar but I thought I'd let you know my compulsiveness came back and bit me (or nibbled perhaps) in the ass. I got my Jetfins on Wednesday (ordered over the internet), size L as my current splits are L-XL and they're too big on me. However, with my pairs of booties on, which are fairly thin, prob 5ml, I have 3.5 inches (9cm) of my foot protruding from the fin. This feels like way to much to me.

I'm a UK size 9 foot (U.S. size 9.5/10). What is the recommended JF size for that (with a bootie) (note: I'm not dry suit diving)? And how much heel/foot should be sticking out the end?

TIA,
John