WARNING - What you are about to read DOES NOT take the place of qualified training!!
The jackstay search is my favorite search pattern and it's the one that confuses the most Public Safety Divers. Having a proper understanding of this one pattern can increase your recovery rate tremendously. Learn it and have it as a key part of your search pattern arsenal.
Why is the jackstay so important? The jackstay underwater search pattern can be a true grid pattern. In land and underwater search and rescue/recovery, a grid pattern is the most accurate pattern when you want to find what you are searching for. In fact, if a grid pattern is used in the search and it is conducted properly and thoroughly by someone who understands the pattern and is comfortable in the conditions under which the pattern is being conducted, you can have up to a 99.9% chance of finding what you are searching for. To get your jackstay to produce a 99.9% chance of recovering the item it takes three things:
1. Knowing how to set up the pattern
2. Two divers that know how to conduct the pattern
3. Two divers that can stay focused while searching while in the environment they are in
After searching the area with a jackstay search pattern conducted correctly and thoroughly, can you look the land investigator in the eye and say, "It's not there," if you didn't find it? You sure can! Can you say, "This area has been cleared!" You sure can! Are you going to find what you are searching for if it's there? You will do so just about every time … if you know what you are doing. So, let's talk about my favorite pattern.
The jackstay search is indicated when you need to be precise and absolutely need to find what you are searching for. It's especially helpful when you are searching for small items but is great when you are searching for medium and large items as well. It can be used when you are close to shore or away from shore and it's the one search pattern that allows you to cover a large area with accuracy. As you can see from its description, this one pattern does just about everything. What more could you ask for!
The three important features of the jackstay search are:
1. The same area is being covered two or more times prior to the divers leaving that area. The area searched by the lead diver (two or three times) will also be searched by the back-up diver (two or three times), the number of times depending on how far the pattern is moved each pass.
2. The divers are able to maintain constant contact and communicate with each other throughout the search in case one should need the other.
3. The complete pattern has up-and-down lines on both ends to assist in making ascents and descents, checking air gauges and bottom times, or for just allowing surface personnel to see the pattern (by its two surface buoys).
Because it involves rigging ropes, downweights, and surface buoys together, many teams are intimidated and shy away from using this pattern, thinking it's too hard or too complicated to set up. I assure you that with a little practice you can become quite proficient in rigging the items and using this valuable search pattern, and you'll be glad you did.
PVC pipe grid patterns
I do not use this type of grid search underwater. It came about through underwater Archeology where research and scientific divers grid off a wreck or reef and count and search for things within the square. Some public safety divers have converted this technique to searching for evidence. I have found that it is slow, does not mold into the environment well (rigid pipe) and can just be too much trouble than its worth.
So, I choose to stay with the jackstay due to it being able to do everything I want it to do, it's simple, and very accurate.
Parts of the jackstay
There are two main parts to the jackstay search pattern:
1. Your up-and-down lines (ascent/descent lines) which include ropes, surface buoys, and downweights. ("Up-and-down lines" is a name I gave ascent/descent lines years ago because it was easier to say.)
2. Your search line (bottom line). Note: Never use rope that floats, like polypropylene rope. Your search line needs to be negative so it lies flat on the bottom.
The equipment you'll need:
Is there a lot more to say about the Jackstay search pattern? You be there is! Unfortunity I don't have the time or the space here to write it all down. I hope this information helps. Good luck in your search and recovery diving!