Maintaining Trim while motionless

[topher10]

Very interesting discussion. We have moved from maintaining trim to maintaining depth.

Lorenzoid's earlier comment does make it seem like I am expecting too much. I guess my main goal is to be stable enough so that I don't break trim or deviate from depth significantly when i am distracted/task loaded. I think the definition of 'significantly' will get more rigorous over time. Basically, i don't want to be messing with something on my safety stop, and suddenly realize I am positioned vertically and at the surface. For instance I had a remora nibbling on me during a recent safety stop, and things sorta fell apart in the distraction of shooing him away and checking for blood. I think doing some of the suggested drills while blinded would be helpful to make me more aware of my body. For instance, just trying to hold depth/trim while maskless, or while writing something. Or following a line as Andy/tbone describe.

Ultimately, all this is unnecessary at my level, but I like having something to work towards, especially during the times I can only get in a pool. An old baseball coach said that you should be working on something every practice swing, instead of going through the same motions as last time. I like taking that approach to diving.

 

[KevinNM]

The SMB deployment drill is designed to task load a student in fundamentals. But it is very easy to lose depth control doing a mask replacement, eventually you figure out how to do it without much change in depth. But the first few times you do it without someone helping by telling you you are ascending or sinking is pretty bad.

 

[RainPilot]

For a ninja tech diver like you, maybe. For a rec diver to be considered good, GUE's standard of 5 ft. sounds pretty reasonable, and for a tech diver 3 ft.

Is that 5ft as in 2 1/2 feet either way or 5ft either way?

So if I am supposed to be at 10 feet and I go from 5-15 ft would I pass?

 

[DevonDiver]

... it is very easy to lose depth control doing a mask replacement, eventually you figure out how to do it without much change in depth...

This, in particular, is aided by doing no-mask drills on a horizontal line. I developed this out of technical wreck training for zero viz... and I'd guess it's no coincidence that cave divers also found benefit in it. You can't lose buoyancy control in a cave or wreck, just because you lost viz... it'd cascade problems.

Adapting it as a drill for general diving improvement has gone well for me - I do see really quick results with students... even the inexperienced ones.

I'm practicing (demonstrating) it all the time. Here's how it works out for me (in a moderate/strong current, so I'm having to back-kick a little that time)..

 

[tbone1004]

For a ninja tech diver like you, maybe. For a rec diver to be considered good, GUE's standard of 5 ft. sounds pretty reasonable, and for a tech diver 3 ft.

I believe it's within those ranges, so +5ft and 3ft. I was giving +1ft, obviously easier at depth.
I also believe that those numbers are while performing drills, not hovering in place. While performing things like valve drills, you have to allow some adjustment to take place. I.e. it's much easier to do a valve drill if you can get a little head down and shrug the doubles up towards your head, when shooting a dsmb, it's nice to go a little head up, etc. 20* is enough for that. The depth adjustments are because you're going to move, but if you can't hover with a fixed reference with +1ft of depth change, then you don't have good buoyancy control. That is for things like holding deco stops, safety stops, taking a macro look at something on a reef, etc. It's not ninja tech diver, it's just good diver.

 

[dmaziuk]

Is that 5ft as in 2 1/2 feet either way or 5ft either way?

So if I am supposed to be at 10 feet and I go from 5-15 ft would I pass?

If you're coming up from 15 feet to 5, you'll likely build up enough momentum to carry you all the way and I expect ending up on the surface will be a fail.

I guess my main goal is to be stable enough so that I don't break trim or deviate from depth significantly when i am distracted/task loaded. I think the definition of 'significantly' will get more rigorous over time. Basically, i don't want to be messing with something on my safety stop, and suddenly realize I am positioned vertically and at the surface.

Since relative pressure differences, and their effects, are greatest near the surface, doing this at safety stop depth is like learning to swim in the deep end of the pool. It's easier below 10 metres.

 

[Lorenzoid]

Is that 5ft as in 2 1/2 feet either way or 5ft either way?

So if I am supposed to be at 10 feet and I go from 5-15 ft would I pass?

I suspect tbone's answer is correct. GUE's wording is "while remaining within 5 feet/1.5 meters of a target depth." So, yeah, that should be good enough for a Rec Pass. I'm currently in the process of upping my game and aiming for a Tech Pass, hence my interest in these kinds of threads. I think I'm going to give Andy's horizontal line blackout-mask drill a try.

 

[KevinNM]

The GUE limits are a window size with the target depth inside the window. So if your target depth is 20 feet stopping at 21 and then drifting to 18 and back to 20 is a 3 foot window.

If you start a drill at 15 feet and drop to 20 and then recover to 16 that's a 5 foot window. If you wander between 11 and 19 that's more than 5 feet.

One of the keys is noticing and fixing deviation from your target fast, when you can correct it with a minor adjustment. The further you let it go the more aggressive your change needs to be and the more likely that you'll overshoot.

 

[RainPilot]

Ok gotcha that sounds right. I do my OW training in a 7' pool and as long as they don't touch the bottom or break the surface then they pass.

 

[topher10]

Since relative pressure differences, and their effects, are greatest near the surface, doing this at safety stop depth is like learning to swim in the deep end of the pool. It's easier below 10 metres.

I know, but when I am deeper I am too busy having fun! But I agree that I should concentrate on these things throughout the dive, while also working on more challenging drills during a safety stop or during pool time.