Wing lift with steel tanks

[sandman98007]

I found a good deal on a OMS wing with AL back plate. The wing is rated for 60# of lift. I dive in cold salt water. With my current set up, (single Faber HP100's.. -7#empty) requires 28# for a good trim an dbouyancy control. Since I want to eventually twin my HP 100's, will this wing configuration give me ample lift, especally at the surface??? As I calculate things, with both tanks full, they should be a -29# in the water. With dry suit and all, will the wing be enough?

Some have told me that I need 100# of lift, but the math just doesn't add up. I am told with this wing configuration that at the surface, it will not support the weight of my 2 tanks when empty and my rig will sink. I am just not sure.

Any input would be greatly appreciated. :06: :06:

 

[VinceDS]

60lb wing will be more than enough.

I currently dive double PST E7-120s, SS BP, 8lb V-weight, and when carrying 2 40's for deco w/ dry suit (and 200gr jumpsuit), my 55# Halcyon wing provides more than enough lift. I am also in a full tech rig w/ can light, reels, bags, wtc.

Whoever told you yo need a 100lb wing for the set-up you are talking about is way off base.

 

[cool_hardware52]

I found a good deal on a OMS wing with AL back plate. The wing is rated for 60# of lift. I dive in cold salt water. With my current set up, (single Faber HP100's.. -7#empty) requires 28# for a good trim an dbouyancy control. Since I want to eventually twin my HP 100's, will this wing configuration give me ample lift, especally at the surface??? As I calculate things, with both tanks full, they should be a -29# in the water. With dry suit and all, will the wing be enough?

Some have told me that I need 100# of lift, but the math just doesn't add up. I am told with this wing configuration that at the surface, it will not support the weight of my 2 tanks when empty and my rig will sink. I am just not sure.

Any input would be greatly appreciated. :06: :06:

A wing needs to do two things; Float your rig without you in it, and compensate for the loss or potential loss of buoyancy of your exposure suit.

You can figure the weight of your rig, i.e. tanks + gas + plate + regs + can lights etc.
All this info is available. Very hard to imagine a rig that's negative by 60 lbs.

How buoyant are you in your DS? Get in the pool with just your undergarment and DS, vent for minimum air. Add lead until you are neutral. What ever this amount of lead is represent the potential loss of buoyancy in a total DS flood. This varies from diver to diver, under garment to undergarment, but usually 20-40 lbs.

Add to this figure the weight of the gas you will breathe down, 200 cuft = 16 lbs.

Lets say you need 36 lbs to get your DS neutral 36+16 = 52 lbs.

I'd worry just a bit about anybody recommending a 100 lbs of lift.....


Tobin

 

[sandman98007]

Appreciate the reply's... and it is as I though.... OMS 60# will be more then enough for any tech diving I plan to do in the future.

 

[cummings66]

Something else to consider, until you start diving with a config that requires this wing you should have a smaller wing. You don't want something that's way too large as it causes it's own problems. In this case bigger is NOT better. Get a wing that's sized correctly for what you will be diving today, not tomorrow.

 

[jepuskar]

Just gonna throw in my 1 cent here.

I have a PST E7-80 that is -10 or -11 pounds in freshwater to start, a 6lb BP so that is about -17 to start off my dive...well lets call it -20 just for the regs etc... I will be using a TLS350 with layered 300 and 150 undergarments, hood and dry gloves.

I have a 27# Pioneer wing I plan on using for this. Whatever other weight I need will go in my DUI Trim pockets so that is ditchable..depending on how much extra weight that is I may also put some on my tank.

 

[cool_hardware52]

Just gonna throw in my 1 cent here.

I have a PST E7-80 that is -10 or -11 pounds in freshwater to start, a 6lb BP so that is about -17 to start off my dive...well lets call it -20 just for the regs etc... I will be using a TLS350 with layered 300 and 150 undergarments, hood and dry gloves.

I have a 27# Pioneer wing I plan on using for this. Whatever other weight I need will go in my DUI Trim pockets so that is ditchable..depending on how much extra weight that is I may also put some on my tank.

A couple thoughts;

If you add a can light, and or add any ballast to your rig (weight on the tanks) you will be very close to the capacity of the wing. Get a little water in the wing and you might be having trouble if you doff in the water. Fortunately you can test whether or not your wing floats your rig pretty easy in a pool. Be sure to drain the wing between dives.

I'd really suggest testing the initial buoyancy of your DS. Put on your undergarments and Suit and get in the pool with minimal air in the suit. Add lead 'till you are neutral. In my experience 25-30 lb is not uncommon, depending on the suit, diver, undies etc.

If you have a total DS flood 27# might not get you back to the surface.

Now as a practical matter you will most negative at the start of the dive, if you need to ditch weight early in the dive, the rapid ascent probably won't be too serious. If you flood late in the dive you may not need to ditch as you tank will be a bit lighter, but not much with a 80.

Good luck, be careful.


Tobin

 

[utdivermatt]

not trying to hijack the thread, but in all reality, why does anyone need wings with more than like 10 pounds or so of lift? If you are weighted properly, you should be balanced with no air in the bladder, right? So from where I stand, I only see you needing lift to compensate for lost buoyancy elsewhere. I know you lose a little when you go down, from change of characteristics of a suit, but other than that, since you dont use it for ascents, what else can it be used for? You even gain some buoyancy throughout the dive thanks to losing air from the tanks. I just dont think I understand which cases you need 20 pounds of lift, much less 80. All this said, my BC has 51 lbs i think, but I am just wondering why?

 

[Dive_Girl PNW]

sandman98007, hearing that you need 100lbs of lift in a wing seems to be a stock answer here in the PNW. Sometimes there exists the bigger is better mentality, go figure. I dive steel doubles and use a 59lb wing, my back up wing is a 51lb wing, which works.

 

[David P]

utdivermatt: I dive (along with many others) a steel tank, that is 1 lb neg at empty and around 12 (?) lbs beg when full of air. I have a stainless steel back plate , 6lbs, a regulator ~2 lbs, lights, snaps, other crap, ~2lbs. That alone is around 22lbs negative. Now when I dive wet I have 17 lbs of lead (I know Im over weighted but with such a large tank, Ive never come up with less than 1500 psi to do a proper weight check). That is now 39 lbs of metal trying to pull my *** down. You want to put on all this gear and jump into an ocean with only 10 lbs of lift?