OP
DeepBound
Contributor
I used about 300cf of gas, but I started with 430cf (double 100's and 3 80cf stages).
I used the rule of thirds to plan the dive, since I definitely wanted to return to my starting point. However if there had been a problem I could have ended the dive by swimming directly to the closest point on shore and either abandoned the gear there or waded back with the gear. Not a nice option, but it was there as a contingency.
My SAC rate is 0.7, and I used 50ft/minute as a rough estimate of my speed. 3000ft along shore at 30ft would take 60 minutes and use up 1.4cf/min or 84cf. The swim out to the wreck from there, about 1000ft with an average depth of 50ft deep, would take 20 minutes and use 35cf of gas. The turn point would be when I had used 1 stage and 1/3 of my back gas, or 143cf, which would only leave 24cf of gas before having to turn, which would only last about 9 minutes at 100ft.
Not being an overhead environment, having 5 tanks and having the contingency plan, I would have gone past thirds a bit to take advantage of the extra 10 minutes of NDL that I had on the wreck, but I didn't have to because pull&glide helped me get there a bit faster and keep my air consumption down.
The tanks all had the same mix, EAN32. According to my Genesis ReactPro computer and PADI tables, I didn't get into deco.
Thanks for the interest. How would you plan this dive?
I used the rule of thirds to plan the dive, since I definitely wanted to return to my starting point. However if there had been a problem I could have ended the dive by swimming directly to the closest point on shore and either abandoned the gear there or waded back with the gear. Not a nice option, but it was there as a contingency.
My SAC rate is 0.7, and I used 50ft/minute as a rough estimate of my speed. 3000ft along shore at 30ft would take 60 minutes and use up 1.4cf/min or 84cf. The swim out to the wreck from there, about 1000ft with an average depth of 50ft deep, would take 20 minutes and use 35cf of gas. The turn point would be when I had used 1 stage and 1/3 of my back gas, or 143cf, which would only leave 24cf of gas before having to turn, which would only last about 9 minutes at 100ft.
Not being an overhead environment, having 5 tanks and having the contingency plan, I would have gone past thirds a bit to take advantage of the extra 10 minutes of NDL that I had on the wreck, but I didn't have to because pull&glide helped me get there a bit faster and keep my air consumption down.
The tanks all had the same mix, EAN32. According to my Genesis ReactPro computer and PADI tables, I didn't get into deco.
Thanks for the interest. How would you plan this dive?
GDI:
