Lift bag

[Wijbrandus]

Ok, someone explain the point of a lift bag to me?

I'm confused. At first I thought it was a dual purpose thing. First, so you have some sort of marker on the surface as you are ascending to keep the boats away (like an smb), and also so you have a line to ascend on, but since it isn't fixed with a weight or to the bottom, that's kind of pointless in a current, isn't it?

Then I figured it was for pulling up anything you might find on the bottom worth salvaging (like a lost anchor). Now I've heard someone say it's a redundancy for your wing in case of failure. Is it one of these, all of them, or none of the above?

 

[Allen42]

Ok, someone explain the point of a lift bag to me?

I'm confused. At first I thought it was a dual purpose thing. First, so you have some sort of marker on the surface as you are ascending to keep the boats away (like an smb), and also so you have a line to ascend on, but since it isn't fixed with a weight or to the bottom, that's kind of pointless in a current, isn't it?

Then I figured it was for pulling up anything you might find on the bottom worth salvaging (like a lost anchor). Now I've heard someone say it's a redundancy for your wing in case of failure. Is it one of these, all of them, or none of the above?

I'm sure you'll receive many answers to this, and many of them will tell you to haul yourself to a class before you kill yourself. I believe most questions deserve an answer, though.

There are many type of inflatable "bags" available to a diver. Each is designed for a specific purpose. There are marker bouys or bags that are intended to be inflated and floated on the surface to mark and object and/or diver(s). There are also lift bags that can be attached to heavier objects to aid in lifting such items off the bottom. Any inflatable device could be used in an emergency as a bouyaqncy device in case of bcd failure.

All of these procedures and techniques require training and practice to perform safely, however. This is why many will tell you to get to a class. The PADI Advanced Open Water (AOW) class will introduce you to lift bags. Marker bouys and deco hang bangs and such are introduced in other classes.

 

[J1M1]

Ok, someone explain the point of a lift bag to me?

I'm confused. At first I thought it was a dual purpose thing. First, so you have some sort of marker on the surface as you are ascending to keep the boats away (like an smb), and also so you have a line to ascend on, but since it isn't fixed with a weight or to the bottom, that's kind of pointless in a current, isn't it?

Then I figured it was for pulling up anything you might find on the bottom worth salvaging (like a lost anchor). Now I've heard someone say it's a redundancy for your wing in case of failure. Is it one of these, all of them, or none of the above?

you dont need a weight to sit on the bottom. You simply inflate the bag, send it up, tie it off on the bottom and you have your own personal ascent line if you are running low on gas and cant find the anchor line. This is especially the case if you have a deco obligation. They can also be used for lifting things to the surface.

 

[Big-t-2538]

I'm confused. At first I thought it was a dual purpose thing. First, so you have some sort of marker on the surface as you are ascending to keep the boats away (like an smb), and also so you have a line to ascend on, but since it isn't fixed with a weight or to the bottom, that's kind of pointless in a current, isn't it?

Then I figured it was for pulling up anything you might find on the bottom worth salvaging (like a lost anchor). Now I've heard someone say it's a redundancy for your wing in case of failure. Is it one of these, all of them, or none of the above?

There's no real single purpose for a lift bag.

They are used as uplines because they can be "shot" from a depth, but no, they are not fixed to the bottom.

They can be used as SMBs.

They can be used to lift artifacts.

They can be used as redundant inflation.

There are more uses I'm sure. The big key however is this: If you plan on using a lift bag, you need to practice with it, so when you need to use it, you are proficent and comfortable with it in any application you plan on using it.

 

[Wijbrandus]

OK, that answers some of my questions.

I'm taking my AOW next month. I'll be sure to ask more detailed questions in class. Looks like I'll be in for a lot of learning in that class.

Thanks for the word. I'm certainly not the kind to go beyond my training, but I was really curious since everyone seems to comment on these items with frequency.

 

[Michael Schlink]

You may or may not get any training with a lift bag in your AOW. If it's a PADI course you should get to pick three dive activities to learn besides the deep dive and the navigation dive. In fact the search and recovery dive may or may not have any value and you might be better off choosing something else. It depends on what type of diving you will be doing. Talk with the instructor and find out what dives they are planning. I let my students choose their 3 elective dives- Dive Safe-Dive Alot-M

 

[Cave Diver]

Ok, someone explain the point of a lift bag to me?

I'm confused. At first I thought it was a dual purpose thing. First, so you have some sort of marker on the surface as you are ascending to keep the boats away (like an smb), and also so you have a line to ascend on, but since it isn't fixed with a weight or to the bottom, that's kind of pointless in a current, isn't it?

Then I figured it was for pulling up anything you might find on the bottom worth salvaging (like a lost anchor). Now I've heard someone say it's a redundancy for your wing in case of failure. Is it one of these, all of them, or none of the above?

As already mentioned, there are numerous uses for bags and numerous types of bags. There are several devices that fall into the general category, including lift bags, surface marker bouys (SMB) and even some of the "sausages."

There are generally two types of bags, open and closed. Open bags normally have a "funnel" at the bottom and can be filled by purging a regulator under them. Closed bags normally require the use of an inflator hose to fill them.

Bags come in a variety of shapes, sizes and colors.

They can be used to lift heavy objects since you never want to use your BC for lifting.

They can be used to mark an object's position.

They can be used to provide an upline in open water.

They can be used to provide a means of reference for both the diver and the boat during extended deco.

They can be used for signalling (one bag is okay, two bags mean trouble. Red bag is okay, yellow bag is trouble, etc.) to surface support.

They can be used as a means of providing redundant lift in the event of a wing failure.

And they can also be used as a barf bag when the seas get too rough...

I'm sure there are other uses that my tired brain cant recall at the moment also.

It's important to note that some types of bags are better suited to some activities than others. As with any dive gear, choosing the correct one for the job at hand is important. There are various methods for deploying liftbags, and there are inherent risks involved with the improper use of them. Practice in a pool or on a shallow dive is highly recommended to learn the finer points before putting the skills to actual use.

 

[DA Aquamaster]

You can use a lift bag for an ascent by deploying it on a reel and drifting with the current (if any) while you slowly ascend reeling in the line as you go. Alternatively, you can use the liftbag to support an upline from a wreck by shooting the bag and then tying the line off on the wreck. A "jersey" reel is normally used for this as the reel is well suited to this type of thing and the sisal rope biodegrades quickly - sometimes on the reel before you use it if you don't dry it out between diving days.

I agree you should either take a class or learn how to use a lift bag for various purposes from someone who knows what they are doing.

 

[Wijbrandus]

Thanks for all the information. My interest was purely academic, since I really haven't had any reason to explore the devices in my beginning diving. I'm just the kind of guy who likes to know as much as possible, and I like to ask a lot of questions.

Appreciate the answers.