Yea, I want to see "Doc" swim aginst a 2 knot current in full gear.
Speed of current
- Thread starter CaptSaaz
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Heh...no grasshopper....'standard operating procedure' in 2 kt current is pull and glide...
(or crank up the Gavin...)
(or crank up the Gavin...)
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Or jump in and enjoy the tidal change of Puerto Galera in the Philippines.
What? You wanted to live forever?
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Try the cuts through the Eniwetok Atoll, five to six knots and all the sharks in the world waiting for dinner at the reef break.
Zieg
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nereas
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nereas
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nereas
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I use Doc's Rule of Reduction:
1 - 2 knots = Wuss diving - standard operating procedure
3 - 4 knots = Pretty rippin'
5 - 6 knots = Watch your mask
> 6 knots = Stay on the boat and drink boat drinks
I don't bother with the math.
The Pugetropolis crew is probably indeed the best at this than anyone else on the Earth, since they need to practice in it every single day, and practice makes perfect.
Using an approximation of 20 inches per second as equal to 1 knot, it's easy to quickly estimate light current, such as I often see where I dive. I certainly adjust my dive plan if I anticipate having to swim against even mild current.
Even a small amount of current, like 0.5 kts, makes me work pretty hard and use substantially more air. I'm sure physically fit divers wouldn't have much of problem.
I'd love to do some drift diving sometime and measure current speed in body lengths! Swimming against current gets old quick!
Dave C
Even a small amount of current, like 0.5 kts, makes me work pretty hard and use substantially more air. I'm sure physically fit divers wouldn't have much of problem.
I'd love to do some drift diving sometime and measure current speed in body lengths! Swimming against current gets old quick!
Dave C
SparticleBrane
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6-second rule for estimating current:
"Current speed (in knots) can be estimated by determining the distance an object travels (in feet) in 6 seconds, divided by 10."
Example:
If the distance a piece of seaweed floating on the surface in 6 seconds was 7 ft: 7/10 = 0.7 = 0.7 knots.
Basis:
One nautical mile = 6,076.11549 ft. Let's round that down to 6,000ft for ease of computation.
If something travels ~6,000ft in one hour, then it was moving at approximately 1 knot, yes? Now just use math:
6000ft/hour = 100ft/min = 10ft every 6 seconds. 10/10 = 1 knot.
"Current speed (in knots) can be estimated by determining the distance an object travels (in feet) in 6 seconds, divided by 10."
Example:
If the distance a piece of seaweed floating on the surface in 6 seconds was 7 ft: 7/10 = 0.7 = 0.7 knots.
Basis:
One nautical mile = 6,076.11549 ft. Let's round that down to 6,000ft for ease of computation.
If something travels ~6,000ft in one hour, then it was moving at approximately 1 knot, yes? Now just use math:
6000ft/hour = 100ft/min = 10ft every 6 seconds. 10/10 = 1 knot.
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