reducing trimix costs

[lermontov]

You don't show the entire dive plan. Have you considered ICD from a switch to air at depth?

yes as well as gas density as Simon mitchel outlines in his lecture- well be doing 5-6 dives with increasing depth so we have time to assess how we are going before committing

 

[Centrals]

What I used when last dived Price of Wales(65m);
Twin set(2x11L, 18/40 or 18/35) + EAN32(travel) + 50%O2 and 100%O2 ie 5 tanks.

The EAN32 given me a bit more bottom time.

 

[Michael Guerrero]

If you're swimming around the ship, and assuming the sand is at 65m, not the top of the superstructure, I wouldn't sweat it. I wouldn't go into a ship that deep without a proper setup though.

 

[huwporter]

The Aaron Ward is 60-65m to the deck, and 72m(ish) to the sand.

In my opinion, it's worth not cutting corners for, and worth every penny of helium.

 

[100days-a-year]

psai.com
I did IANTD Deep Air class prior Tri mix
I am a very accomplished deep air diver with thousands of dives beyond 130 on air.
Most were solo.
I prefer mix and a buddy for past 60m or deep penetration dives.YMMV.

 

[Pullnglide]

Don't take offense but your posts are a bit alarming and don't take offense to anything I say since I don't know you, your training, your experience and may have overlooked something in this thread. I may have missed it but it seems you keep mentioning "trimix" without mentioning the mix you plan to use. Trimix isn't just adding Helium to reduce narcosis. What experience do you have diving with helium? Have you completed any helium mix courses i.e. Adv. Rec. Trimix, Normoxic, Hypoxic? What travel gases have you used and what mix were you needing a travel gas for (mentioning travel gas didn't make sense for a question about a 65m dive)? It seems as though your jumping in way too deep for your experience, literally! It also seems that your going on a "trust me" dive with a instructor friend that may be experienced with helium and says we'll give you a little trimix and you'll be fine. Forgive me if I'm off base here.

 

[Remy B.]

planning a trip to Aaron Ward (65m) and thinking about using air to say 40m and carrying a 12l stage with trimix for last 20 m then swapping back to air for ascent ( then to deco gas) any issues /problems anyone can see with this? main reason is to keep costs down - regularly dive to 36m on air and feel pretty comfortable at that depth in low vis cold water
Im a sidemount diver and usually dive with deco and travel gas so also pretty comfortable with gas switches

I'm curious what bottom trimix % are you planning to use ?, I'm a rookie diver and I see flaws in what you want to attempt, I guess the experienced ones are freaking out.

 

[Nasser]

You don't show the entire dive plan. Have you considered ICD from a switch to air at depth?

While the OP dd mention a max bottom depth of 65m which generally speaking ICD isn't as a much of an issue as in deeper hypoxic ranges , I couldn't help thinking the exact same thing... at least regarding possible future deeper dives.

Honestly lermontov, I think it's best to tighten up any loose ends and get the proper training for TX and if you want to do deeper air dives, do Extended Range (deep air) to fill in the blanks and then have the knowledge to make an informed decision.

cheers,
Nasser

 

[lermontov]

While the OP dd mention a max bottom depth of 65m which generally speaking ICD isn't as a much of an issue as in deeper hypoxic ranges , I couldn't help thinking the exact same thing... at least regarding possible future deeper dives.

Honestly lermontov, I think it's best to tighten up any loose ends and get the proper training for TX and if you want to do deeper air dives, do Extended Range (deep air) to fill in the blanks and then have the knowledge to make an informed decision.

cheers,
Nasser

cheers - working on it!

 

[Peter69_56]

planning a trip to Aaron Ward (65m) and thinking about using air to say 40m and carrying a 12l stage with trimix for last 20 m then swapping back to air for ascent ( then to deco gas) any issues /problems anyone can see with this? main reason is to keep costs down - regularly dive to 36m on air and feel pretty comfortable at that depth in low vis cold water
Im a sidemount diver and usually dive with deco and travel gas so also pretty comfortable with gas switches

What about isobaric counterdiffusion? I was always taught to take that into consideration. Oh I see others have already commented on that. Personally I dont wish to be bent underwater, regardless of the theory of it not being an issue above 100m.

You should be using a travel gas to minimise the nitrogen change? Up to you. I just used air when I dived the Aaron Ward as mainly I was on the deck at about 55m or so and 67 to the sand (just looked up my dive profiles).