Navigation practice

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Doctor Rig

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Location
Michigan
# of dives
I just don't log dives
I’d like to set up some underwater buoys that can be used for navigation practice. The lake bottom is essentially featureless and the visability is 10 to 15 feet at best. For divers who are familiar with navigation but would enjoy the practice, what distance(s) would you a recommended from a starting buoy to the target destination buoy?

I already have two sunken boats on the bottom that could easily be used, but they are about 100 yards apart. I’m thinking this is to far, what’s your thought?
 
50 yards. Remember in underwater navigation the further you cover a distance the further you most likely to get away from the point (heading) you choose. Along you path you need to find natural features or man made item to keep track of your heading. So basically along these 50 yards make sure there is some point of reference. A 100 yards seem a bit excessive.
 
You should be able to follow a compass heading in a no-current lake for at least 100 ft, and spot your target given 10-15 ft viz. Practice at 50 ft if necessary. Get good at 100 ft. extend that to 200 ft, then 300 ft. You do not need intermediate markers on the bottom...they just defeat the learning how to follow the compass. Counting fin kicks while swimming is a good exercise to give some task-loading, and incidentally to give you practice in estimating distances. Ideally you'd learn to head for a target (say) 200 ft away, know when you have gone 200 ft, and then do a circular search if necessary from that point to look for the target.
 
If you have 3 or more targets you can attach instructions for reaching the next rather than having a map.
 
100ft sounds reasonable and is really only about 20 fin kicks or less.

On a side note, when teaching basic navigation, I used a large grass field next to the high school pool that we used for confined water. Bring a large towel and a small towel. Go to the middle of the field with your compass. Drop the small towel on the grass. Then drape the large towel over your head so that you can't see anything but your compass. Set your single point bezel to North and then follow the lubber line for one hundred paces. Then set your double points to North and follow your lubber line for a hundred paces as a reciprocal back to your starting point. You should end up very close to the small towel. Once you master basic reciprocals, then move on to rectangular, triangular, offsets and more complex patterns.
 
In the U.S. Naval School for Underwater Swimmers, they had us start at 500 yards, and proceed to 1,500 yards. In the photo below, my buddy, Bob Means and I are on the 1,500 yard compass swim. You can see Bob has the compass on his left wrist, is holding that wrist onto his right hand, which we used to tell direction. We were allowed to surface at the 1,000 and 500 yard marks to ensure we were oriented correctly. But we still had divers trying to swim to Cuba instead of the island where Key West was located.

Now, there is a sport sanctioned by the World Underwater Federation (CMAS) called Underwater Orienteering, which holds competitions in swimming a compass course. You can see their website here:

CMAS shows several types of orienteering courses, including an "M" course, a "Star Course" and a "5 Points" course. They say that there are usually "...usually 80, 100, 120, 150 and 200 meters..." between points. You can see their description here:


As can be seen in this video, the Europeans have taken this underwater orienteering competitions to an entirely different level, with use of the monofin, and specialized hand-held scuba units streamlined with a compass for the orienteering work.


Enjoy,

SeaRat
 

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In the U.S. Naval School for Underwater Swimmers, they had us start at 500 yards, and proceed to 1,500 yards. In the photo below, my buddy, Bob Means and I are on the 1,500 yard compass swim. You can see Bob has the compass on his left wrist, is holding that wrist onto his right hand, which we used to tell direction. We were allowed to surface at the 1,000 and 500 yard marks to ensure we were oriented correctly. But we still had divers trying to swim to Cuba instead of the island where Key West was located.

Now, there is a sport called Underwater Orienteering, which holds competitions in swimming a compass course. You can see their website here:

CMAS shows several types of orienteering courses, including an "M" course, a "Star Course" and a "5 Points" course. They say that there are usually "...usually 80, 100, 120, 150 and 200 meters..." between points. You can see their description here:


As can be seen in this video, the Europeans have taken this underwater orienteering competitions to an entirely different level, with use of the monofin, and specialized hand-held scuba units streamlined with a compass for the orienteering work.


Enjoy,

SeaRat
The worst possible compass to use is one on a console; it is very hard to get it oriented correctly right in front of you. One on your wrist is good, if you use that hand to grip the other wrist so the compass is directly in front of you. Better is a compass on a board with hand holds that you can keep in front of you. A good instructor will help you get the compass oriented correctly, so you don't swim to the left or the right of the desired course.
 
The interesting thing about some compasses on a counsel is that they are oriented differently, and some {like my Suunto compass) is offset so that you can look at it from behind. There is a viewing window in the side of my compass that allows it to be viewed from the eye level area. It's not advertised, but I discovered that feature on mine.
 
The consoles with compass on a 900mm hose on all my gear, take me wherever anyone would need to go

364 26232328_1795887217119559_5507116560859510058_oa.jpg


The console when diving was simply stealthy and funner

Come now how many of you get that wrist stuff hung up
 
50 yards. Remember in underwater navigation the further you cover a distance the further you most likely to get away from the point (heading) you choose. Along you path you need to find natural features or man made item to keep track of your heading. So basically along these 50 yards make sure there is some point of reference. A 100 yards seem a bit excessive.

You should be able to follow a compass heading in a no-current lake for at least 100 ft, and spot your target given 10-15 ft viz. Practice at 50 ft if necessary. Get good at 100 ft. extend that to 200 ft, then 300 ft. You do not need intermediate markers on the bottom...they just defeat the learning how to follow the compass. Counting fin kicks while swimming is a good exercise to give some task-loading, and incidentally to give you practice in estimating distances. Ideally you'd learn to head for a target (say) 200 ft away, know when you have gone 200 ft, and then do a circular search if necessary from that point to look for the target.

100ft sounds reasonable and is really only about 20 fin kicks or less.


You guys are so adorable, 100ft, 100yards???? My students, in entry level courses, swim no less than 500 meters in a reciprocal course. Their graduation dives involves swimming to target rock and back to exit point underwater 500 meters out and 500 meters back. It is a NAUI course so maybe that's why.
 

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