Pony tanks Good or Bad? - POLL

[TCooperWFI]

Redundancy is a good thing ( pony bottle or Doubles )!

Well said. Has anyone ever been over redundant?

TC

 

[pipedope]

Department of redundancy department.

 

[TCooperWFI]

What is the minimum redundancy requirement?

 

[MikeS]

What is the minimum redundancy requirement?

IMO the minimum redundancy is a buddy with two second stages and sufficient gas to get both of you to the exit point (i.e. anchor line) and to the surface safely at a 30 fsw ascent rate with a 3 min safety stop at 15 ft.

 

[NEWreckDiver]

According to some people, if you have a pony bottle, you will either make bad decisions or get entangled in something.

The argument just doesn’t make sense to me.

 

[TCooperWFI]

Redundancy is good, you can't have too much of a good thing.....

 

[MikeS]

IMO it’s better not to have pony if you don’t understand it’s capabilities/limitations and practice with it on a regular basis. Otherwise it can result in a false sense of security that may cause one to get careless and into trouble. If through ignorance and lack of training you do not understand gas management, a pony will not necessarily help you and may result in your putting yourself in an unsafe situation. How many divers that use a pony can say that they don’t perhaps stray a bit further from their buddy, knowing that they have it?

If you can’t calculate how much gas it may take you and your buddy to safely surface from a given depth (i.e. 100 ft.) then in my opinion, you shouldn’t be using a pony.

If you can’t explain why you chose the size pony you did and estimate how long it will allow you to stay at your maximum depth, you shouldn’t be using a pony.

If you’re not comfortable with regulator exchange and clearing a regulator with no air in your lungs, you shouldn’t be using a pony.

However, if you have an understanding of gas management and practice the associated skills on a regular basis than taking a pony as a bailout bottle is a good thing in that it gives you additional options in an OOA situation.

Sure doubles or an h-valve might be a better option but they’re not always practical.

Mike

 

[TCooperWFI]

Stupid people do stupid things and bad things happen to people who don't plan properly and as long as they make incorrect assumptions or don't take the time to learn all the facts....

 

[NEWreckDiver]

You are diving a single tank w/o a pony and have just arrived at your max depth of 120' and plan to work your way back up from there after a minute or two.

You hear bubbles and realize that your second stage to regulator o-ring has failed completely.

You signal to your buddy, point out the problem, call the dive and begin your ascent at 60fpm checking your SPG occassionally. You notice at 60' that you still have plenty of gas left in your 72 so you slow the ascent to 30fpm and make stops at 30', 20', and 10'. Then you make a slow ascent to the surface where you still have over 1000 psi.

Change scenario by adding pony.
Would you go to the pony? At what point?

Additionally:
Does the pony allow you to stay at 120' longer?
Does the pony allow you to go deeper?
Does the pony allow you to go over the NDL?
Does the pony allow you to stay at any point in the dive longer than your back gas would allow you to access the surface?

If everything went as laid out in your scenario, I would not have to go to the pony would. Silly question.

Does the pony allow you to stay at 120' longer? Of Course Not
Does the pony allow you to go deeper? Of Course Not
Does the pony allow you to go over the NDL? Of Course Not
Does the pony allow you to stay at any point in the dive longer than your back gas would allow you to access the surface? Of Course Not

I think I understand your argument, it is not a question of should you use a pony bottle, but are you trained and do you understand how to use it and its limitations. If this is the case, I agree with you. If it is not, then you really can’t make a argument not to have one in deeper NDL dives. All divers should be self-reliant; you cannot always depend on a buddy. Entanglements can’t be a argument, because you can get entangled without one.

 

[MikeFerrara]

O.K. how's this?

Dive site U352, off-shore NC.
Max depth 115 feet.
Visibility expected 20-100 fsw.
Current expected none to slight.
Water Temperature expected 70 degrees

Equipment configuration:

TX-100 / TX-40 with long hose and bungeed backup
PS HP120 tank (3500 psi), 300 BAR DIN K-valve
Air Integrated Computer (Cobra)
SS BP&W with Pioneer 36 and ACB Weight system
2.5 mm full wetsuit

Bailout Bottle: Stage slung pony AL30 with DS4/TX40 and SPG

Dive Plan:

Descend following the anchor line to wreck and swim around the wreck.
Return to anchor line when first buddy down to 2300 psi (2/3) or at ½ NDL for 120 feet.
Surface, hopefully on the anchor line NLT when the first buddy hits 1200 psi
Ascent rate 30 FSW/min with 1 min stop at 50 fsw and 5 minute stop at 15 fsw.

Hypothetical Scenario 1: On the way back to the anchor line a lp hose bursts resulting in an explosion of bubbles and a rapid loss of back gas.

Option(s) without pony:
Locate buddy as alternate air source, attempt to return to anchor line but start direct ascent when down to 1200 psi.

Option(s) with pony:
Locate buddy as alternate air source, attempt to return to anchor line but start direct ascent when down to 1200 psi.
Switch to pony as alternate air source

Analysis Questions:

Is the rig complication as a result of adding the pony worth having an additional option in an OOA situation?

Is there a better configuration for obtaining the same or similar option?

Even without penetration at 115 I do prefer some redundancy although it can be done without even if a low pressure hose does burst. I'd probably dive my doubles. For a wreck dive to 115 I'd for certain want a bottle of 50% or O2. I don't at all care for 100+ planned as a no stop dive. It's one thing to dip to that depth on a reef where most of the time will be spent working your way up but for a wreck at 115 I'm just going to plan some deco and have the gas to do it.

I would be carying more but I'd have the option of more time on the bottom and more time on the ascent with a better gas to breath on the way up.

I use to do dives like that with a single tank but I never really enjoyed it because the dive was short and I wasn't comfortable with the the short no stop time or the gas situation. About the time I started thinking I needed a pony, I started planning deco, wearing doubles and slinging deco gas. I'd have a ball on that wreck now.

Also I'd likely use a dry suit even there but with a wet suit I'd double up a set of al80's. They'd be great for those shallow wrecks and wet suit diving. Even if done as a "no stop" dive with a single gas, for about the cost of a
pony and reg you could have a mnifold and a set of bands. I'd make a deco bottle out of the pony. That gives me both more gas and better gas fo the ascent.