Dive-planing with dolphins youtube video

[chris mac]

Originally Posted by PPLepew

It's not how deep or how long you are under, just a combination of the two.
This would not be recommended in deep waters. So being down 15-20 feet for a short fun ride is harmless.

Taking a breath from your hookah at 15 -20 feet and not exhaling as you go up will be very detrimental to your lungs, 15 feet to surface is half an atmosphere of pressure. That means the volume of air in your lungs at 15 feet will be 1.5 times more at surface forcing your lungs to expand 50%
The ride could be only short, not so much fun.

[Travis McGee]

Originally Posted by PPLepew

It's not how deep or how long you are under, just a combination of the two.
This would not be recommended in deep waters. So being down 15-20 feet for a short fun ride is harmless.

I do not believe it would be safe to take in a lung full of compressed air at 15 feet depth and then surface in a half second without exhaling. The risk of an air embolism would be very real if rapidly ascending and descending, which is what a dive plane does best. Think of an underwater roller coaster. Take great care if breathing compressed air at depth not to turn the board upward. The ascent rate with a dive plane is much greater than what a diver is normally expecting.

And 15 feet is minimal. On a 75 foot towing line, at 3.5 knots, a dive planer with good ear function can easily swoop down to 30 feet and back up in about 2 seconds. Because it's so easy to surface to take a breath, I don't see much advantage to dive planing with compressed air.

[cwyckham]

Originally Posted by Travis McGee

I do not believe it would be safe to take in a lung full of compressed air at 15 feet depth and then surface in a half second without exhaling. The risk of an air embolism would be very real if rapidly ascending and descending, which is what a dive plane does best. Think of an underwater roller coaster. Take great care if breathing compressed air at depth not to turn the board upward. The ascent rate with a dive plane is much greater than what a diver is normally expecting.

And 15 feet is minimal. On a 75 foot towing line, at 3.5 knots, a dive planer with good ear function can easily swoop down to 30 feet and back up in about 2 seconds. Because it's so easy to surface to take a breath, I don't see much advantage to dive planing with compressed air.

Very well stated. The risk seems to outweigh any perceived advantage.

Just to be clear to everyone: An "air embolism" is when the lung tears due to the compressed air in it as the diver ascends. Air gets into the bloodstream. The consequences can easily be fatal. Like dead fatal.

This has absolutely nothing to do with "the bends" where dissolved gasses bubble out of your blood as you ascend. An embolism is a sudden tear in the lung and has nothing to do with how long you've been at depth.

The percent change in pressure with depth is greatest in the first 30' where you would be planing and this means this is actually the area where the risk is the greatest.

[Be Free]

Daniel,

Your reply is addressing the absorption of nitrogen in the blood which is dependent on depth and time. The major concern with using a hooka or any type of compressed air with this device would be changes in pressure caused by changes in depth.

Please do not use compressed air with this device. The dangers are too great. I have seen this happen in less than 15' of water when a student held his breath during an emergency ascent drill. The hospital was only a few blocks away and he survived. You may not be so lucky.

[Training Wheels]

It's possible to embolise in 4' of water.


Sent from my iPhone using Cruisers Sailing Forum

[Dsanduril]

Actually, the science says 4' is all that is required:

Experimental evidence indicates that intratracheal pressures of about 10 kPa (4 fsw or 1.22 m....

Arterial Gas Embolism

[Travis McGee]

Glad to see we are mostly all on the same page about NOT dive planing with a compressed air source (SCUBA or Hookah). It's not needed anyway, since you can surface in less than one second anytime you feel you need a breath. I don't even usually take a snorkel, since the dive plane holds your entire head out of the water when it's angled upward and planing.

[PPLepew]

It's the same problem with scuba diving, why should I hold my breath if I had a respirator in my mouth.
But let's do some math here:
You stated 15' in 1/2 a second. That's 108000' or 17.8 nautical miles, straight up. What speed is your Rocket Propelled Speed boat trailing you?

[lateral]

"why should I hold my breath if I had a respirator in my mouth."

Anxiety from any number of sources has been attributed as the the reason for holding breath on ascent. Mouth piece or not.

[Travis McGee]

Originally Posted by PPLepew

It's the same problem with scuba diving, why should I hold my breath if I had a respirator in my mouth.
But let's do some math here:
You stated 15' in 1/2 a second. That's 108000' or 17.8 nautical miles, straight up. What speed is your Rocket Propelled Speed boat trailing you?

Go ahead, do what you like. Don't blame everybody who tried to warn you when your lungs explode from over pressure and you are dead.

[Travis McGee]

I wonder if anybody has made their own plywood dive plane yet, and tested it?

[Cormorant]

I've made two now. . . . One to keep aboard my boat, and one as a gift for a buddy with a boat down on Long Island. I visited him a couple of a weeks ago and presented him the SEALplane, but alas, his boat had recently parted a shroud and was out of commission till it gets repaired. So no testing by me till next summer, sad to say.

I hope others in warmer climes can make some and post the videos here.

[Travis McGee]

Let me know when you get a chance to use it, or your friend in the Keys.

I wish I was still out sailing in warm water, I won't have another chance for months.

[Nicholson58]

We all might find this interesting. Look ahead to 25 minutes in for an alternative to swim fins.

https://www.youtube.com/watch?v=6Vk2L39ycLM

[robert sailor]

Very cool, enjoyed the vid