Buoyancy techniques

[Osric]

Edit: deleted. I had misinterpreted who you were responding to.

 

[elan]

I disagree. Bad trim plays a direct role in incorrect buoyancy.

If the diver is swimming with a 'head up/feet down' attitude, then their propulsion/thrust will be compensating for buoyancy. Depending on the angle of bad trim, a corresponding proportion of thrust is directed downwards. This means less effficient forward motion, but also serves to propel the diver upwards in the water column. This, in turn, leads to three issues:

(1) The diver will believe that they need more weight to compensate for excessive and unexplained 'buoyancy'.
(2) The diver will have less air in their BCD than necessary, because their fining is providing upwards thrust (interpreted as 'buoyancy').
(3) Any time they cease fining, they will sink, because they aren't actualy neutrally buoyant.
(4) If the diver is actually neutrally buoyant, they will rise in the water when they start fining.

You cannot achieve proper buoyancy control, unless you have good trim in the first place. It is the foundation and needs to be in place.
View attachment 96407View attachment 96406

While what you are writing is correct its irrelevant to what I posted. If the driver desides to swim in any direction realizing it or not its a dofferent story. You also operate on some assumptions that the dive believes... This is not necessarily applicable to each case.
Even if my static trim is completely off - say im vertical thereis nothing that will stop me from swim horizontal. And how what you describe would be fixed with a wing ? That what the poster was asking originally

 

[DevonDiver]

I wasn't addressing the issue of wings, although I do believe that wings offer a slightly more instinctive transition into good trim because of weight distribution across the length of the upper torso.

What I was addressing is that your statement didn't specify any link between trim and buoyancy - which is a significant omission, given that the thread OP is a novice diver who is seeking to improve their buoyancy and may not have understood how improper trim plays a significant role in the buoyancy woes of many divers.

 

[elan]

Alright, agreed.
There were much more stuff omitted in my original post though

But I found your post is very beneficial for novice divers anyways. It Should be made stuck at the top of basic scuba section.

 

[CPH]

This article was posted on Yorkshire divers a while back by Gareth Burrows and it really helpped alot of people.


http://www.yorkshire-divers.com/forums/surface-interval/145643-trim.html