What do you think of descent rate on this profile? ~ Conch Wall

[IncreaseMyT]

They said hot drop, I said don't threaten me with a good time At 80 feet you can see I stopped, wondering where everyone was.

 

[Billy Northrup]

So am I reading that as about 80ft in 90 seconds? Good decent speed is a skill especially hot dropping wrecks. Doddle along and you glide over the ship in a current.

Pro tip: The capt will drop you upstream and guestimate your decent vs current to get you on the spot. It best to show up early and drift into it. Get a compass heading from the capt, currents can be a different direction on the bottom.

Have fun!

 

[abnfrog]

I useually do 50 feet per minute , I don't like going faster than 60 fpm.... but im a co2 loader and I find slower down works best for me

 

[Billy Northrup]

I useually do 50 feet per minute , I don't like going faster than 60 fpm.... but im a co2 loader and I find slower down works best for me

No s***! Good call, I remember doing a 260 footer, dropping down on 25/25, gas switch to 15/60 all good and smooth.... Double check, this is fun..Oh look, there is the ship and start kicking excitedly and BOOM wheels come off. So I stopped and thought I should have more than enough HE here, but I stopped and about as quick as it came it went. Shazzam

 

[boulderjohn]

I have only had to do one hot drop in the last few years, and that was a couple months ago. We were told there was a raging current, and we were dropped quite a ways from the wreck--maybe 300 feet. The current was indeed raging, but only for about 50 feet. After that, it wasn't bad. We dropped as fast as we could. We all hit the sand, I am sure well short of the wreck, and then used our compasses. Visibility was horrible--maybe 15 feet. We could barely see each other. No one in our group found the wreck. No one.

I later talked with a veteran diver and skipper who said you should descend on a hot drop at a normal rate, and it is a mistake to drop too fast. If you do, he said, you are too likely to be just a few degrees off on your compass heading and pass the wreck in the darkness--which is what happened to us. He said that if the skipper gives a proper drop, and you drop at a normal rate, you should land on the wreck.

 

[boulderjohn]

I realize that the topic of this thread is hot dropping onto a wreck, but I want to make a slightly different comment on fast drops.

I used to dive with someone on technical dives who would go as fast as he could on a drop and then wait for everyone else to get there. My rough calculations had him at 100 feet per minute, and that was for decompression dives over 200 feet down. He absolutely did not believe in computers, and he used a standard dive planning algorithm with a bottom timer, as we all did.

The problem is that the algorithm assumed a descent speed of 50 FPM. Let's look at a dive to 300 feet for 15 minutes to see what difference that makes. He could get to the bottom in 3 minutes,and the rest of us would get there in 6. That means that at the 6 minute mark of that 15 minute dive, he would have an average depth of 225 feet, and we would have an average depth of 150 feet. At the end of 15 minutes, his average depth would be 270 feet, and our average depth would be 210 feet. Put those numbers into a software program and see what it does to the ascent profile.

 

[Vicko]

Most of the divers here go as fast as possible, usually with scooters pulling them down. I personally also enjoy gliding down at around 40m per minute.

In case of high currents on wrecks most currents shift in the water collum, sometimes on a deep wreck you have a strong north current above the termocline and then a south current bellow it, so hot drops are a gamble.
Considering a lot of my customers are tec divers that don't really have that much experience diving in my area I found that a very thin shot line (3-5mm) with a counter weight at the surface works great, since we used that system we did not miss a wreck once. The counterweight holds the marker as vertical as possible reducing the drag from the current and in case someone does drag the shot line while going down it absorbs a lot of that movement.

 

[scubadada]

My planning software uses 60 ft/min. I usually descend at about that rate, sometimes faster in brisk current to ensure I hit my target for solo drift dives. This is a good example, I did the first 60 feet in 30-45 seconds and then slowed after I hit my target on the reef to make about 75 feet in a minute.
Teric SAC rate confusion

 

[johndiver999]

A good descent rate is beneficial, but often it takes more skill to descend completely vertically. Any divergence from vertical results in lateral displacement and if this displacement happens to be perpendicular to the actual or predicted current direction, then you are off the mark and can mis the target, especially if it is small or narrow.

It is sometimes very important to descend vertically and I do this with an inverted kicking position. Any divergence from vertical messes me up. It is also Maybe more important to immediaty descend upon entry, rather than ear drum shattering speeds.

 

[IncreaseMyT]

Yea for sure, at my home diving sites finding the wreck, or piece of the wreck can be difficult so it is important to get right down there. Usually a back roll off the gunwale with no air in your BCD. The running joke discussed after the dive is usually "Rob left air in BCD and couldn't get down lol"

Plus with my Zeagle if you flip face up I become more negative, and some of the way down I was face up trying to see if they were coming.

This is def a steep one for me, I was overweighted, first time diving my sons steel 100. I bet if I didn't stop I would have hit 100 in under 90 seconds. I thought it was a cool looking profile