Recreational Pony Bottles, completely unnecessary? Why or why not?

[Gareth J]

There is a concept of the correct tool for the job.

For many years I dived twin 12’s (litres) (doubles) prior to that I used twin 10’s.

Walking along the harbour I bumped into an some I new who was shocked to see me in a single and pony.

We had been diving from a RIB (Rigid Inflatable Boat), doing 20m wreck penetration dives. There was insufficient space for twins on the boat. But redundancy seemed sensible when doing single file limited penetration dives.
In fact we actually ran some out of air exercises as part of the weekend.

Similarly I once made the mistake of doing some shallow shore dives in twin 12’s. It almost killed me walking around the harbour and across the rocks getting in and out from the dive.
Never again. Now I would use a single and pony.(or twin 7’s).

One of the nicest OC rigs for shallow diving is a set of twin 7’s. Light, with redundancy and more gas than a single. But it is ‘another set’ to keep in test.

If you are teaching. A single with pony is perfect.
The benefits of a pony become questionable below 30/35m.
Then you really want to be on twins. They give you sufficient gas for the depth and any accrued decompression stops that need to be completed.

 

[Gareth J]

All U.K. diving fatalities are in the BSAC Incident Reports, if it was not a club dive or no BSAC members were involved to submit a report then the entry might rely on coast guard or RNLI reports.

BSAC is a membership organisation run by very active divers. Those people are all very aware of what really goes on.

Successful dives are not reported to HQ, they are supposed to be recorded by the local branch but often not as it is a bit of a hassle and not entirely obvious to people as why it is worth while.

As @KenGordon says, all uk fatalities (and accidents) involving divers in the uk irrespective of diving organisation or qualification are captured by the BSAC incident report.

The RNLI, Coastguard, Navy, Recompression facilities report incidents directly to the BSAC.
They also have a news capture service.
That does not include the reports from members, directly and indirectly involved in incidents

I would second @KenGordon suggestion that you read the BSAC incident reports. They are freely available on the BSAC website.

Annual Diving Incident Report

The Annual Diving Incident Report contains details of UK diving incidents occurring to divers from all agencies and backgrounds, plus incidents occurring worldwide involving BSAC members.

www.bsac.com

Link added

 

[KenGordon]

On Sunday, weather allowing, I will do a 24m wreck dive using a single and a pony. The reason for that is my buddy will be a AOW with a few dozen dives and this will be his first U.K. sea dive and my first dive with him. That rules out CCR for me, my twinset is loaned out, so to have a sure source of gas in the case of a failure I am taking a pony.

I have a choice of sizes, I could use a 3l dil cylinder or a 7l bailout - I will probably use the 7 as it involves less hassle and is just plenty of gas. My main objection to the SB view on ponies is that people seem to think a small cylinder is ok and sometimes talk about 6 or 13 cuft ponies. There is also little consideration of the downsides, confusing regulators, a false sense of security and plain inadequate size.

I much prefer diving with redundancy and with a buddy with redundancy. This makes things much more relaxed. You can loose sight of each other and it is not a big deal, usually you will find each other and not need to abort.

 

[Wibble]

There is a concept of the correct tool for the job.

For many years I dived twin 12’s (litres) (doubles) prior to that I used twin 10’s.

Walking along the harbour I bumped into an some I new who was shocked to see me in a single and pony.

We had been diving from a RIB (Rigid Inflatable Boat), doing 20m wreck penetration dives. There was insufficient space for twins on the boat. But redundancy seemed sensible when doing single file limited penetration dives.
In fact we actually ran some out of air exercises as part of the weekend.

Similarly I once made the mistake of doing some shallow shore dives in twin 12’s. It almost killed me walking around the harbour and across the rocks getting in and out from the dive.
Never again. Now I would use a single and pony.(or twin 7’s).

One of the nicest OC rigs for shallow diving is a set of twin 7’s. Light, with redundancy and more gas than a single. But it is ‘another set’ to keep in test.

If you are teaching. A single with pony is perfect.
The benefits of a pony become questionable below 30/35m.
Then you really want to be on twins. They give you sufficient gas for the depth and any accrued decompression stops that need to be completed.

In a word, sidemount, using 7s or 8.5s

Small, lightweight cylinders. Fully redundant and sublime in the water.

 

[Gareth J]

In a word, sidemount, using 7s or 8.5s

Small, lightweight cylinders. Fully redundant and sublime in the water.

Why would I go to side mount?

I would need a side mount rig. Plus another set of cylinders. If I wanted 7’s I would just get another manifolded set.

If I was diving tight spaces, or had a bad back there might be some justification.
The biggest weakness with side mount is the fact they are un-manifolded.

My current backplate moves from single to twinset to CCR. Plus one smaller wing for singles.
I have maximum flexibility with what I have. (For the type of diving I am doing).

 

[BoltSnap]

The biggest weakness with side mount is the fact they are un-manifolded.

Why would you want tanks "manifolded"? Why is that a weakness with SM?

(I am not disputing at all, I just want to understand your point of view here).

 

[Rukkian]

Why would you want tanks "manifolded"? Why is that a weakness with SM?

(I am not disputing at all, I just want to understand your point of view here).

The manifold allows for full use of all gas, even if you have a 1st stage failure. While you can feather a tank that is having issues, it is not the same. It does add more complexity and another potential point of failure, but that is slight. This is the prime reason the consensus is manifold vs independent back mounted doubles.

 

[Celt]

Why would I go to side mount?

I would need a side mount rig. Plus another set of cylinders. If I wanted 7’s I would just get another manifolded set.

If I was diving tight spaces, or had a bad back there might be some justification.
The biggest weakness with side mount is the fact they are un-manifolded.

My current backplate moves from single to twinset to CCR. Plus one smaller wing for singles.
I have maximum flexibility with what I have. (For the type of diving I am doing).

You’re dead right, there’s no justification for splitting a lovely set of 7,s to side mount them. You can’t improve on perfection. Twin 7,s are as good as it gets scuba diving. Wish I could squeeze the air in my 12,s into my 7,s

 

[Wibble]

The biggest weakness benefit with side mount is the fact they are un-manifolded.

FIFY

Nothing like having proper redundancy, simple access to the valves, everything in front/side of you, sublime trim and streamlining...

Sigh. The season's just ended

Must do some mine diving...

 

[Wibble]

The manifold allows for full use of all gas, even if you have a 1st stage failure. While you can feather a tank that is having issues, it is not the same. It does add more complexity and another potential point of failure, but that is slight. This is the prime reason the consensus is manifold vs independent back mounted doubles.

So you wouldn't end the dive if a 1st stage broke, returning to the exit/surface with the surviving independent cylinder?