Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 29-09-2015, 21:04   #46
Registered User
 
chris mac's Avatar

Join Date: May 2015
Location: edmonton alberta
Boat: 1980 san juan 7.7
Posts: 279
Re: Dive-planing with dolphins youtube video

Quote:
Originally Posted by PPLepew View Post
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.
__________________

__________________
chris mac is offline   Reply With Quote
Old 30-09-2015, 05:05   #47
Registered User
 
Travis McGee's Avatar

Join Date: Mar 2005
Location: Jax, FL
Boat: 48' steel cutter
Posts: 291
Re: Dive-planing with dolphins youtube video

Quote:
Originally Posted by PPLepew View Post
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.
__________________

__________________
Travis McGee is offline   Reply With Quote
Old 30-09-2015, 12:54   #48
Registered User
 
cwyckham's Avatar

Join Date: Apr 2011
Location: Vancouver, BC
Boat: Niagara 35
Posts: 1,869
Re: Dive-planing with dolphins youtube video

Quote:
Originally Posted by Travis McGee View Post
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.
__________________
Chris
SailMentor.com - Become the Confident Skipper of Your Own Sailboat
cwyckham is offline   Reply With Quote
Old 30-09-2015, 15:00   #49
Registered User

Join Date: Nov 2012
Posts: 43
Re: Dive-planing with dolphins youtube video

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.
__________________
Be Free is offline   Reply With Quote
Old 30-09-2015, 17:31   #50
Registered User
 
Training Wheels's Avatar

Join Date: Aug 2014
Location: Left coast.
Posts: 525
Re: Dive-planing with dolphins youtube video

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


Sent from my iPhone using Cruisers Sailing Forum
__________________
Training Wheels is offline   Reply With Quote
Old 30-09-2015, 17:51   #51
Registered User
 
Dsanduril's Avatar

Join Date: Aug 2011
Location: Oakland
Boat: Cross 40
Posts: 1,394
Re: Dive-planing with dolphins youtube video

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

Quote:
Experimental evidence indicates that intratracheal pressures of about 10 kPa (4 fsw or 1.22 m....
Arterial Gas Embolism
__________________
Dsanduril is offline   Reply With Quote
Old 01-10-2015, 10:58   #52
Registered User
 
Travis McGee's Avatar

Join Date: Mar 2005
Location: Jax, FL
Boat: 48' steel cutter
Posts: 291
Re: Dive-planing with dolphins youtube video

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.
__________________
Travis McGee is offline   Reply With Quote
Old 02-10-2015, 12:00   #53
Registered User
 
PPLepew's Avatar

Join Date: Jan 2012
Location: Wherever the boat lies, USA
Boat: Island Spirit 40' Cat
Posts: 44
Re: Dive-planing with dolphins youtube video

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?
__________________
Daniel - aka Pepe Lepew
PPLepew is offline   Reply With Quote
Old 02-10-2015, 13:09   #54
Registered User
 
lateral's Avatar

Join Date: Apr 2011
Location: NZ
Boat: S34 Bob Stewart - 1959 Patiki class. Built by me & good mate.
Posts: 519
Re: Dive-planing with dolphins youtube video

"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.
__________________
lateral is offline   Reply With Quote
Old 03-10-2015, 07:48   #55
Registered User
 
Travis McGee's Avatar

Join Date: Mar 2005
Location: Jax, FL
Boat: 48' steel cutter
Posts: 291
Re: Dive-planing with dolphins youtube video

Quote:
Originally Posted by PPLepew View Post
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 is offline   Reply With Quote
Old 22-10-2015, 05:56   #56
Registered User
 
Travis McGee's Avatar

Join Date: Mar 2005
Location: Jax, FL
Boat: 48' steel cutter
Posts: 291
Re: Dive-planing with dolphins youtube video

I wonder if anybody has made their own plywood dive plane yet, and tested it?
__________________
Travis McGee is offline   Reply With Quote
Old 22-10-2015, 08:45   #57
Registered User
 
Cormorant's Avatar

Join Date: Jan 2009
Location: Catskill Mountains (too far from the sea)
Boat: 31' homebuilt Michalak-designed Cormorant "Sea Fever"
Posts: 1,818
Re: Dive-planing with dolphins youtube video

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.
__________________
Cormorant is online now   Reply With Quote
Old 24-10-2015, 07:36   #58
Registered User
 
Travis McGee's Avatar

Join Date: Mar 2005
Location: Jax, FL
Boat: 48' steel cutter
Posts: 291
Re: Dive-planing with dolphins youtube video

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.
__________________
Travis McGee is offline   Reply With Quote
Old 24-10-2015, 13:05   #59
Registered User
 
Nicholson58's Avatar

Join Date: Jan 2011
Location: Grand Rapids, Michigan
Boat: Camper & Nicholson58 Ketch - ROXY Traverse City, Michigan No.668283
Posts: 3,448
Images: 83
Re: Dive-planing with dolphins youtube video

We all might find this interesting. Look ahead to 25 minutes in for an alternative to swim fins.
__________________
Nicholson58 is offline   Reply With Quote
Old 24-10-2015, 13:23   #60
Registered User

Join Date: Sep 2012
Posts: 4,471
Re: Dive-planing with dolphins youtube video

Very cool, enjoyed the vid
__________________

__________________
robert sailor is online now   Reply With Quote
Reply

Tags
dolphins

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Anyone Else Have YouTube Video ? minaret Monohull Sailboats 31 27-07-2012 17:49
My First YouTube Video delmarrey General Sailing Forum 24 29-11-2009 10:30
YouTube video on shaft packing 5 " shaft Roy M Propellers & Drive Systems 5 24-07-2008 10:07


Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 15:24.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.