THE "PERFECT ( being horizontal ) TRIM" HOAX

[Mr. Dooley]

Interesting post. I practice in the pool every week and one of the main things I'm trying to improve is trim (along with breathing, propulsion, and buoyancy).

I feel for a lot of diving, there's a real benefit to being able to do the horizontal trim. If you're flutter kicking straight ahead with your body at a 30 degree angle, and you want to stop to check something out, what happens? You sink because you'd been using propulsion to maintain depth instead of solely relying on neutral buoyancy. Similarly you'd have to work harder than someone in "perfect" trim to cover the same distance which means you'll go through your gas faster. It makes sense to me to try to be the most efficient diver possible.

On a drift dive, horizontal trim wouldn't necessarily be optimal for the same reason - efficiency. So I agree with others who've noted that different techniques are suited for different environments.

All that being said, I think people should dive in whatever way keeps them (and others) safe and comfortable.

 

[Pressurehead]

Neutral buoyancy is a hoax. Fake news. I have people that have seen 2000 divers in Wisconsin quarry's claiming to be neutral, but weren't. There are places in Pennsylvania that people that were not even divers were claimed to have neutral buoyancy. And don't get me started on Arizona, more people claimed to have neutral buoyancy than the lake could hold. Wake up sheeple, they are trying to steal neutral buoyancy from those of us that have perfect trim.

So funny, fake news, where have I heard that before?

 

[Jerome O'Neil]

He had taken GUE Fundamentals and some other courses from Andrew Georgitis when he was Director of training for GUE, and he fairly worshipped the guy. By then Georgitsis had been fired by both GUE and then NAUI. When he then formed UTD, our instructor crossed over to UTD and the Georgitis version of DIR, and all the students had to cross over, too.

Way back in the 90s Andrew was working for (or out of or on behalf of, it's been a while) 5th Dimension Scuba in Kent, just down the road from me. He did a presentation there on videography he did for the "Inside the Britannic" documentary. The presentation was fantastic. But it did make me think that all these guys with reputations as colossal assholes, when viewed through the dives they are doing and their combined safety record, may be onto something. Same story with a lot of those WKPP guys. I probably wouldn't have them over for dinner or anything, but I keep in mind more people have been on the moon than have been in the caves where they've been.

I'm not one for personality cults, but it is tough to argue results.

 

[dmaziuk]

Neutral buoyancy is a hoax. Fake news.

Neutral buoyancy is a contradiction in terms.

Buoyancy (/ˈbɔɪənsi, ˈbuːjənsi/)[1][2] or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object.

If upthrust is "neutral", there is no upthrust, so the proper term is "nonexistent buoyancy".

 

[EFX]

Technically, buoyancy is an upward force. The term "neutral buoyancy" as described by divers should really be called "neutral position" where the upward buoyant force exactly balances the downward force of the diver's weight. Another misnomer: NDL. It should be called NSL (No Stop Limit).

Here's a formula for calculating the net force from all components on the diver for those who are interested:

B = VD - W

where:
B = Buoyant (total) force in lb (+ floats, - sinks, and 0 is neutral)
V = Volume of the object in cubic feet (ft3)
D = Density of water in lb/ft3 (fresh = 62, salt = 64)
W = Dry weight of the object in lb

Metric equivalents:
Weight (B): 2.2 lbs = 1 kg (kilogram)
Volume: 1 ft3 = 0.0283 m3 (cubic meter)
Density: 1 lb/ft3 = 16 kg/m3 (Fresh = 992, Salt = 1024)

Edit: sorry for the repeat definition. I didn't see the definition in the above post. Mmmm.....to much in a hurry.

 

[TMHeimer]

I don't have perfect horizontal trim. My legs and fins are negative (I guess the legs, even with the 7 mil wetsuit). My BC weights and belt are as far toward my head as possible. My "legs down" situation is barely noticeable. I received compliments from instructors when assisting OW courses on my buoyancy and trim, so I guess I work it so no one notices. It's so slightly out of line that it's not worth the bother to start attaching small weights to my tank or other odd places. When shell hunting with an instabuddy I will remain 3' off the bottom so as to not stir up sand. Most of my dives are solo, so should my fins touch a sandy or silty bottom on those dives and kick up a little it's bothering no one, so nose to the ground. Whatever works.

 

[Blackcrusader]

Wait, let me understand... are you saying that they shouldn't be doing that?

I never knew ascending in the hull of a boat was taught anywhere.

 

[Blackcrusader]

I thought good trim/form made you a better diver same as in skiing. I’m intrigued by the trim side mount divers achieve. They seem to glide effortlessly in perfect trim like a fish.

Fish will use whatever position they need to be in. When you are in the sardine run when the thresher sharks jack fish giant trevally are in a feeding frenzy you won't see that DIR horizontal trim. These sleeping fish are using the Anenome but in all sorts of positions.

 

[Open Ocean Diver]

Fish will use whatever position they need to be in. When you are in the sardine run when the thresher sharks jack fish giant trevally are in a feeding frenzy you won't see that DIR horizontal trim. These sleeping fish are using the Anenome but in all sorts of positions.

I was thinking something more like this:

 

[Blackcrusader]

I was thinking something more like this:

Would love to do a shark diving adventure with her. One of mine but a far less deadly shark.