Boat diving tank size? Bottom time?

[oregondiver]

I have been reading through this forum and didn't see this addressed much.

Someone posted (a while back) that a boat dive had AL60's. Is that normal? Or do most boat diver operators have AL80's?

I also read that boat dives were running about 30 minutes long. Even for an AL60 that seems super short. Is it just the experience level of the divers and the experienced ones need to dive the same way/time as the rest of the divers on the boat which results in shorter dives?

Or can the experienced divers just stay down (if they can find a buddy with similar air consumption/skill level) until they are ready?

I hope I read something wrong (ie one divers misconceptions?)

Thanks very much!
Shell

 

[MauiScubaSteve]

One post in the past decade has mentioned "AL60's", it just happened to be in the last few days. Do you know of any AL60's in the scuba world? Did you notice all the responses to the post with "AL60's" in it?

Sarcasm dialed down - there are often AL63's on boat dives in warm water locations; sometimes there are even AL50's. That is because some petite divers (or petite breathers) don't need 80 cf to make typical warm water boat dives.

There is one boat operator here in Maui County that mostly uses AL72's for their charter customers. That is really only 5 cf less than an AL80, as they really only hold 77 cf.

The timed length of a dive, no matter if it's from shore or boat, is directly related to profile. There are quite a few dives in Hawaii that are shorter than 30 minutes, some even shorter than 20 minutes, even for divers who are not hoovers and have dive computers.

The vast majority of boat diving in the State of Hawaii is guided diving and depending on the company and the dives, often you will not get to stay down until you are ready to ascend

 

[oregondiver]

Sorry.

 

[DiveMaven]

On Maui at least, AL80s are standard on most charters. The noteable exception is Lahaina Divers who uses AL72s as their standard tank.

 

[vinegarbiscuit]

My LDS uses AL80s as standard. But if you're a super-regular and your diving skills/awesome air consumption are well-known to the shop's staff, dive guides and the boat captain, they might pack an Al63/Al 50, if requested.

The length of a boat dive will depend on the site. I've gone on shallow dives (~30 feet) lasting slightly over an hour. I could have stayed even longer, but there's a fine line between making the most of your bottom time and being considerate to other customers who have surfaced before you, especially when topside conditions are crummy and they're feeling sick. Then there are deep dives (~100 feet) where NDL time will dictate everything, resulting in a run time of less than 30-minutes. Ultimately, run time on any dive site here in HI really depends on the site and the experience levels of the divers on board that particular day.

 

[MauiScubaSteve]

I tried to indicate that there was sarcasm in play, hard not to for me.

For trips with students and Intro's, dive sites would be less than 60', but the typical first dive that I know of would be 60-100', with second dives 30-60'.

If you do a 30 minute dive with ~15 minutes ~80', then a 45 min SI, a second dive to 60' might only be ~30 minutes, due to nitrogen. That happens.

 

[friscuba]

I've dove in Maui with three operators, not mentioned yet but all good, one used 80's on the first dive with table profiles, then "dive your computer" as long as you don't go over 60 minutes with al72's, the others used 80's and provided long computer profile driven dives for us.

In Kona it seems the standard, if you look at everyone, is al80s overall. I'm thinking one of the largest operators uses al72s unless larger is requested, another op uses steel72s. If they're doing their profiles right the slightly smaller tanks don't matter, a guide can dive deep and fast and get a short dive out of most divers on any tank if they really want to. We do see 63s on the ops that cater to Japanese tourists, maybe even a few 50s. Dive times run the gamut, the night dive is pretty much timed by every operator (times may vary by operator), the day dives depends on the operator... some try to limit it, some will put the good divers in first and bring them out last, some will let 'em dive their air as long as the DM still has air. Longest dive I've led has been around 100 minutes. Nearly every dive site here has 100'+ water and 25-40' water so you can get deep and still spend the bulk of the dive in 30-40' of water and get a long dive if you're good on air. It's best to check with the various operators on their bottom time policy if dive length is a concern.

 

[k374]

I was the one who posted about the AL60 because I had read it a few places on the web, other references were AL72, no need for sarcasm I was just trying to clarify that is all... I am paying a huge premium to dive in Hawaii compared to the Caribbean and it would really suck to pay more and have a bad experience... thats all.

 

[Chocoholic]

I must have read the same post because I was wondering too.
I am going in September and I don't want my dive cut short by smaller tanks. I am used to at least an hour to dive but that's Caribbean diving; easy, warm water, light current. I guess I'll call around and find out what the Dive OPs use and why and if we get to dive our own plan.

With that note I will be diving with two newly minted divers so I'm thinking they will need the biggest tanks and will still be surfacing way early.

 

[MauiScubaSteve]

I will reiterate; the vast majority of charter boat diving in the State of Hawaii is guided diving. Typically, with a full boat, there will be ~6 guests following a guide. A few boats have groups as large as 8 guests following a guide (one I know of). There are also many trips where groups may be smaller than 6 guests following a guide.

There are also many dive sites and charter trips where the first dive will be less than 40 minutes in duration, followed by a 45 - 60 minute SI and then a second dive up to 60 minutes, if your air and computer allow.

edit; If you do a deep first dive at Molokini (+130' is possible at many Molokini sites) and then after a 45 minute SI the second dive is the St. Anthony wreck (square +60' profile), it is easy to not get more than 30 minutes on both dives, due NDL's. end edit.

For the petite breather a 72 cft does not change the above information. If you are not a petite breather you could request/pay for a larger tank or go with an operator that normally uses 80 cft's (all but one operator I know of).

There are some regular visitors who are allowed to dive there own plan with the operators they are regular visitors with, but there are very few first time visitors who will be able to dive their own plan unless that plan is to follow the guide.