Speed of current

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I have to believe the currents in Colorado are not that bad, .


The water is too cold to move.
 
We teach students the following:

6 feet in 10 seconds is 1 knot.
Right numbers, wrong order. 1kt is 10' in 6 seconds.

10' is a reasonable distance to judge by eye.
Working from 10' in 6 seconds you can come up with easy combinations for the typical ranges of speeds ----

10' is 3 seconds is a scorching 2kts
10' in 6 seconds -- 1 kt
10' in 12 seconds -- 1/2 kt
10' in 8 seconds = 3/4 kt (6 sec divided by 3/4 = 6 * 4/3 = 8)

=====================================================

Another effective way of getting a good estimate of the current is to ask everyone on the boat how fast the current was on the previous dive AND THEN DIVIDE BY TWO!

For a more scientific sounding guess, divide the consensus estimate by pi. :)
Joking aside, divers, even including DMs tend to seriously overestimate current speeds, usually by about a factor of 2.


Charlie Allen
 
We teach students the following:

6 feet in 10 seconds is 1 knot.

Which is offically Thass' definition of a knot but in easy to see terms. THis is useful for measuring current before you get in, and if you are stationary in the water and a piece of kelp goes by and you time it floating from head to foot, or head to fin depending on your actual height.

Sleep deprivation and kids with flu result in my brain fart. It's 10 feet/6 seconds not the other way around. Geez. See this is a perfect example how having kids can make you dumb. :D
 
We teach students the following:

6 feet in 10 seconds is 1 knot.

Which is offically Thass' definition of a knot but in easy to see terms. THis is useful for measuring current before you get in, and if you are stationary in the water and a piece of kelp goes by and you time it floating from head to foot, or head to fin depending on your actual height.

Don't you mean 10 feet in 6 seconds?

A knot is 100 feet per minute. So a tenth of that would be 10 feet in 6 seconds. Most of us divers don't travel much faster than 1.5 to 2 knots, so bucking a one-knot current is serious business.

Oops, edit to the above: I'd only read to the end of page one, then posted, now I realize there were 4 pages and I'm out of date.

More coffee.
 

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