Diving Performance - Beyond Drag (article Series And Discussion)

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The irony when you streamline the kit and have half a meter of weight belt dangling below you :D.

Looks fast, still not convinced of it's use but well...

Is your site down btw @REVAN ?
 
How many knots is this ?
The finswimming record is about 7 knots, I think. That's with no scuba equipment and a monofin that is so tight on the feet that it can be worn for about 10 minutes at a time (fin swimmers end up with deformed feet, similar to ballerinas).

The irony when you streamline the kit and have half a meter of weight belt dangling below you :D.

Looks fast, still not convinced of it's use but well...

Is your site down btw @REVAN ?
I haven't addressed the weight belt situation yet. I'm still dealing with more pressing development issues, but the weight belt will eventually need to be addressed. The belt tail was tucked in and out of the way when I got in the water, but those things have a tendency to pop out, and it did.

The website is down presently. The same thing happened last year as well. The bill comes due, and after payment, their server doesn't recognize the payment being made and takes the site offline anyway. Then it seems to take them forever to respond to a help ticket to reactivate it. It's frustrating as Hell! Hopefully it will be back online soon.
 
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I've been away for a few months, and in that time I was able to put together a short video on my 1960 Scubair regulator, and vintage diving using minimum equipment. I also showed off a little of the Sea Turtle/Dolphin swimming style I developed. Realize that you are looking at an ol' geezer, who is using extremely old equipment but in a new way.
Enjoy,

SeaRat
 
I also showed off a little of the Sea Turtle/Dolphin swimming style I developed.

If you mount a couple action cameras at the ends of your Hammerhead foil it will be similar to my camera bar. This works well, as the large foil dampens the shaking motions the diver tends to inject into the video. It makes for better video quality as well as adding an interesting perspective angle if you turn the camera back to film yourself. It looks a lot more interesting than having a camera on a stick directly out in front of you.

My camera bar doesn't have the pivot in the middle, but I haven't noticed that being an issue. Have you tried a rigid one without the pivot?
 
If you mount a couple action cameras at the ends of your Hammerhead foil it will be similar to my camera bar. This works well, as the large foil dampens the shaking motions the diver tends to inject into the video. It makes for better video quality as well as adding an interesting perspective angle if you turn the camera back to film yourself. It looks a lot more interesting than having a camera on a stick directly out in front of you.

My camera bar doesn't have the pivot in the middle, but I haven't noticed that being an issue. Have you tried a rigid one without the pivot?
Revan,

Unfortunately, that would no work too well with the Hammerhead Unit. The reason is because I use it both for propulsion with an up-and-down motion, using the unit as fins similar to the way a sea turtle uses its front fins. In addition, I use them for steering, by independently changing both sides in opposite directions to roll. This is similar to the ailerons on an airplane wing, except the whole wing rotates. So i don't simply plane the hammerhead unit, but rather use it in much the same manner as a sea turtle or whale. If I were to put a camera on the outside of the foil, people would get pretty seasick watching the video.

Years ago, like in the 1970s, I tried a fixed wing system, and did not like it. I had little directional control (couldn't roll with that configuration).

SeaRat
 
Is your site down btw @REVAN ?
The website is down presently. The same thing happened last year as well. The bill comes due, and after payment, their server doesn't recognize the payment being made and takes the site offline anyway. Then it seems to take them forever to respond to a help ticket to reactivate it. It's frustrating as Hell! Hopefully it will be back online soon.
I just checked and the website is finally back up again. Took them long enough too. I was just about to give up and cancel the payment on them. I need to move to a new web hosting service. :mad:
 
Read the first part and half of the second. To me it sounds like an infomercial for a product in search of a solution to a problem.
 
Update:

After many iterations and concept changes, I have a kit that I like diving. A new job and other priorities that have taken me out of making fins and other dive gear professionally, but I'm happy to have my new gear and new capabilities for myself. I'm not going to have a lot of time to dive in the next year or two, so full testing will happen slowly. This kit is too fast to be able to collect good metrics in my 20 meter pool, so I'm not sure exactly how to benchmark it beyond saying that it feels fantastic. It is so fast, that adding a couple GoPro cameras to the kit makes the kit noticeably more draggy; impressive, as GoPros are quite small. I'd like to find a way to attenuate that GoPro drag because I like to film things when I'm diving, but it is a literal drag to take them along.


This dive was a lot of swimming and then sitting and waiting, looking around, and repeating. This was only the 4th dive on this kit as it is currently configured, so I'm still keeping things pretty conservative (especially since I must dive solo to test the expanded performance envelope). True distance is unknown as there was a lot of random wandering, but the following minimums were extracted from the map based on the extents of my roaming. Current was minimal, so no reason to push the speed. This kit achieves a solid 2 knots at a resting level RMV, and that's what I was doing on this dive when I was moving.

Stats this dive:
* Total Distance Covered - 1.6 miles
* Surface Swim Distance - 0.4 miles
* Max Depth - 68 feet
* Average Depth - 40 feet
* Submerged Dive Time - 90 minutes
* Total Air Consumption - 50 cubic feet (from an AL80)

As far as air consumption goes, it usually doesn't matter if I'm just sitting around or swimming. Unless I want to start swimming faster than 2 knots, which is usually not necessary, an AL80 will last a very long time. With further testing, I expect to find that this kit cruises well at 3 knots (especially without the GoPros attached).

This winter, I repaired a leaking ballast tank regulator and replaced the 2nd stage hose with one that is the proper length for this kit. I'm hoping to be able to get it in the water again sometime in May.
 
https://www.shearwater.com/products/peregrine/

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