What size wing for new BP/W?

[mscmicrobiology]

I tried the buoyancy calculator but seems to be really overestimating what I will need in my new BP/W and wanted to get some opinions.

My current rig consists of:
Zeagle Ranger BCD (with Stiletto wing - 35lbs) - I typically don't need any/little air at all in the wing during dives.
Mares Power Plana Fins
Waterproof W4 5mm Full Wetsuit
Waterproof 6.5mm B1 Boots
Waterpoof B1 1.5mm Socks
Apeks XTX 200 + XTX 50 octo (standard flex hoses)
Apeks Basic SPG
Shearwater Perdix AI
Atomic Venom Frameless Mask
Aqualung Squeezelock Titanium Dive Knife
Light and Motion Sola 2500 Dive Light - hand strap (primary dive light)
ScubaPro Nova 200 (back-up dive light)
Single 80cu ft Aluminum Tank (most common liveaboard tanks)

My current stats are:
Height = 6'2"
Weight = 175lbs

My new BP/W will likely consist of:
Apeks Deluxe One-Piece Web Harness
Apeks Stainless Steel BP
and either A) Apeks WTX 18lb Wing or B) Apeks WTX 30lb Wing (or eventually both).

Where I dive:
90% of dives are singletank (aluminum 80s) liveaboard in warm/temperate open saltwater with max depth of 130' (~100-150 divers per year).

Weight (lead) required to trim out perfectly with my current rig:
8lbs (4lbs in each trim pocket on upper CAM band)

So the new steel backplate should weigh in at ~5lbs. I'm sure the new BP/W should be less floaty than my ranger by likely a few lbs. The big question is whether the 18lb wing will be sufficient lift for where I dive most of the time? If so, will I require the 30lb wing if I start using steel tanks/hood/7mm full suit in colder water? Any estimates as to my new weight (lead) requirements with my new BP/Wing to trim out again?

 

[decompression]

If I can save you some money......just get the 30......it’s super streamlined and well designed so you won’t have the usual issues with a large wing. It’s a fantastic wing for warm and cold water. Although you might want to consider an AL plate if you are only using 8 lbs.....can always add a bit more later or pick up a Steel plate.

 

[lowwall]

Whatever your kit, you are properly weighted if you are neutral on the surface with a (nearly) empty tank or tanks. If you can achieve this, then for wet diving, the lift you need is equal to the weight of air the tank(s) hold when full plus the difference in buoyancy of any neoprene you are wearing between the surface and max depth.

Let's just consider single tank diving here since you'd need a different wing for doubles anyway. An AL80 holds around 6 pounds of air. So a 6 pound wing is sufficient if you are willing to dive in a bathing suit. A 3mm fullsuit is around 5-6 pounds more buoyant at the surface than at depth. Add another pound or two for the boots, and you are still comfortably inside the lift on an 18lb wing even if you add a hood or thin vest or a 120 cubic foot tank (but probably not all at the same time). This is why an 18lb wing is sometimes known as a "tropical wing".

OTOH, a large 7mm fullsuit with hood may be 20 pounds more bouyant at the surface than at 100'. Add 6 + 20 and you can see why a 30lb wing is the recommended all-rounder.

The 5mm is borderline. It will work with an 18lb wing if it's not XL and there's no hood, but a 25lb wing is a better choice as it will give you leeway to add a bit of extra thermal protection.

 

[halocline]

Your lift requirement is basically the buoyancy of your wetsuit plus the weight of the gas in your tank. This is assuming you are properly weighted. If you only need 8 lbs in your current rig (and can hold a stop with a near empty tank) then it sounds like your wetsuit has about that much inherent buoyancy, so 18 lbs of lift should be fine. I have one of those 18 lb oxychec wings and I love it. The 30 lb oxy is not that much bigger.

 

[DeepSeaExplorer]

Our stats are very similar. I need 6lbs of ballast in saltwater with a 2mm shorty.

My lightweight travel rig is a carbon fiber plate with a 20lbs wing.

My other rig is a SS plate and a 30lbs wing, with no additional ballast.

Basically, I need 6lbs in saltwater. I get that either by using a SS plate or adding weight to the carbon travel plate.

 

[lowwall]

Note that required wing capacity is only indirectly related to the lead you'll need to carry. Wing capacity is solely determined by the amount of lift you would need to get off the bottom in the worst case scenario of full tanks and the deepest depth you will go to. Again this comes down to the weight of gas in the tanks plus the difference in buoyancy of your exposure protection between the surface and max depth.

The lead you'll need to add (or not) is whatever it takes to get your kit underwater at the beginning of a dive. This depends on the net buoyancy of the diver and everything he or she is wearing. A fluffy diver in a big jacket BCD and a 3mm may need 25 lbs of lead, but will be fine with an 18lb wing. OTOH, a skinny diver with a steel backplate, HP120, and a 7mm may need only 6 pounds of lead, but will still need a 25 or 30lb wing.

 

[DeepSeaExplorer]

A diver is heaviest at the beginning of the dive and typically needs weight at the end of the dive to maintain a stop. (Talking warm water diving here.)

I could dive an AL80 with no weight at all because of the weight of the air in the tank. Where I would be in trouble is during the ascent after I burned that air weight. I would be too buoyant. I need 6lbs to hold a stop at the end of the dive. I’m not wearing a thick suit, so the weight is not to get down, but to stay down at the end.

I use a 20lbs wing for warm water diving because I carry limited gear. On more advanced dives where I might take additional gear like a canister light or an extra tank, I use a bigger wing for the additional lift.

 

[mscmicrobiology]

Thanks for the advice. It sounds like the Apeks WTX 30lb wing might be my best choice if similarly streamlined to the 18lb one. I was just hesitant as my current Zeagle with 35lb lift wing is quite oversized and don't want to repeat my error. I want a minimalistic setup that still meets my requirements in most situations. I am hopeful the stainless steel BP will bring me close to neutral without much additional weight, though I could always add a lb or two to the trim pockets on my CAM band.

 

[RyanT]

I agree with @decompression, just get a 30lb wing and be done with it. It's a rather streamlined wing, so you won't notice any additional drag in the water vs. something like a 20 lb wing. If, however, you find yourself needing to ride a little higher in the water on the surface, need to assist another diver on the surface, or switch your setup to a heavier steel tank, that 30 lb wing will serve you well.

 

[drk5036]

Thanks for the advice. It sounds like the Apeks WTX 30lb wing might be my best choice if similarly streamlined to the 18lb one. I was just hesitant as my current Zeagle with 35lb lift wing is quite oversized and don't want to repeat my error. I want a minimalistic setup that still meets my requirements in most situations. I am hopeful the stainless steel BP will bring me close to neutral without much additional weight, though I could always add a lb or two to the trim pockets on my CAM band.

I used 4 kg (8.8 pounds) with a rental BCD, and upon switching to my steel Freedom backplate, I don't require any extra lead.

I have a 23 lbs VDH wing and a 30 lbs DGX wing. I bought the VDH wing first. It is a bit smaller and nicer for travel, but I didn't feel it was enough lift in a 8 mm semidry and steel tanks, so I bought the 30 lbs wing also. I really like it, and if I could go back I would buy the DGX wing first (then in the future, buy the the 18 lbs VDH wing). I guess you'll likely end up with both, but the 30 lbs wing is more flexible.

Also, if you haven't seen it, check out the DGX wing. It's really cheap and good quality I believe. DGX Singles Wing - 30lb lift | Dive Gear Express®