Welcome back to Smarter Every Day! Today, we want to focus on the search aspect of search and rescue that the US Coast Guard uses. We visited Sector Mobile on the Gulf Coast of Alabama, where we met with Captain Allen, who is in charge of the Coast Guard assets in that area. She explained that they use various search patterns, depending on the object being searched for, such as a person in the water with or without a life jacket, or a capsized boat. They then input this data into the SAR database, which spits out a search pattern for them to follow.

We also saw a brief moment of modeling and simulation software that the Coast Guard uses to find people. The purple objects seem to be simulations of probable locations, and the black line appears to be a search pattern. The first one makes sense, as it covers the entire area from one side to the other. The other pattern, however, is less intuitive, as it consists of triangles which may not be the most efficient way to cover an area. So what’s going on with that? This weird shape is a concept the Coast Guard uses called a Victor Sierra, otherwise known as a sector search. It’s always a very interesting problem that occurs when you search for someone on water. Let’s say you went on a hike and you lost something. The right thing to do is just go back to the last place you remember having your item, and it’s probably in that general area. This works because land doesn’t move. Water, however, does move, and it can even change flow directions over time. If you were to go back to the same place where you lost the thing, it’s probably already drifted away on the water. Understanding that drift that Captain Allen was talking about, you remember when I did that, that drift, that’s the key to finding people because I thought that the cases would just roll up in their boat and just start looking around, maybe use a search light at night or something like that. But no, they have to do two things really, really quickly. They have to first find the drift of the water. But they also have to start searching. And this Victor Sierra kind of does that. And the cool thing about Coast these is that their training is standardized, so it doesn’t matter where you go, talk to a coastie They all know how this works.

So what I’d like to do is I like to go talk to coasties from two different locations and see if we can understand that we’re actually going to do a Victor Sierra down here in Florida. But first, I want to go up to Station Rochester in New York on Lake Ontario. This is bosun’s mate second Class Lucas, Western Lucas and the rest of the crew showed me the RBM, a response boat medium that they used here at the station. And once we went into the station, I got a chance to ask them about what a Victor Sierra is.

So what we’re doing for a Victor Sierra sector search is we are trying to look for a small search object and very well known location. Destin - OK what you’re doing with those triangles is your covering a small area a lot. So as you’re searching, you’re actually moving with the current or the winds to figure out how fast the water is moving, whether it’s by wind or by currents. And then the direction is moving the thought process behind it as if someone’s fallen overboard. They’re not going to drift against the wind or against the current. So you want to follow the direction that they started to drift in.

If You don’t speak Coast Guard, it might be difficult to understand what he was saying. So let’s just go do one. Let’s go down to Station Destin in Destin, Florida, and let’s learn how to do it. Victor Sierra search pattern. Obviously, I think Station Destin is really cool because my name is Destin, but the cool thing about this particular trip is I went on Memorial Day weekend, which is the busiest weekend of the year for this station. There’s this little makeshift island that pops up just offshore from Station Destin called Crab Island, saw a bunch of people go party and all kinds of stuff. It was a really interesting time to visit at one point while hanging out in the cafeteria and just getting to know some of the coasties. I learned one of the most important things that the Coast Guard taught me.

All right, so this is Justin. And he’s going to teach me how to whistle because you whistle at the college. Kids, right? Yeah. So you’re going to put your hands together to your guns. I think you should line up finger guns. All right. Fingers together. Destin - Yeah. And all you do is you just push your tongue back and bang down. Destin - Back? What do you mean? Destin - Cause is. ( really really loud whistle sound ) Destin - hold on wait what did you do with your tongue? Destin - let me see it, so you push it back. Destin - Uh-Huh. And fold it over, Destin - uh huh? And you just blow Destin - All right alright you want to hold that? finger guns like that. Justin - Yeah. Knuckles together…? Justin - So your pinkies? You see these two lines right here. Destin - Yeah. Justin - So the first one is going to be 200.

Justin - “Line those up.”
Destin - “OK. Got it!”
Justin - “OK, then fingers together and you want to hold your tongue over.”
Destin - “Uh huh!”
Destin - (Destin whistles and is in pure amazement)
Justin - “And then blow down. Holy cow. Are you serious. DUDEEE?”
Justin - “Once you get that down, you can do it with one hand the same way.”
Destin - (Freaking out) “Are you serious?”
Destin - (Whistles loudly) “Justin, thank you so much.”
Justin - “You are welcome. There was a moment, dude. OK. Obviously, that was awesome. Anyway, the next day, before Crab Island started to form, I have to go see them prep one of the boats for the day. This is an RBM response boat medium. It’s a 45 foot long jet boat, and this is one of the workhorses of the Coast Guard. Ortize showed me some of the secrets of the boat as they were getting things ready, and it’s awesome. I get to go out with them later and do some of their drills with Shepherd and Lebeouf. That’s Justin who taught me how to whistle. They took the RBM several miles off the coast out into the deep water to do some training, and this is where I started to understand that nuclear sign we saw on the SAR OPS software.”
Justin - “All right, let’s do a victor Sierra.”
Destin - “Do a what? So it’s a search pattern. It’s a it’s a drifting search pattern. So we use this if, say we someone says we get a radio call and Coast Guard, I’m in this position of the person in the water and we fly out there and we get on scene and we don’t see anybody. We’re going to do what’s called a sector search or a Victor Sierra search pattern. And you know, you’ll see more of what we run through, but basically that drifts with the current. You and draw it. Yeah. So I’ll I’ll show you what a Victor Sierra looks like on paper. And then we get down. I’ll show you what it actually looks like, taking into consideration the the current and the drift Shepard - want me to take the sticks? (meaning control of the boat)”
Justin - “Yeah, go ahead. So you’re taking control, taking control.”
Justin - “So if this is the starting position, Victor Sierra is going to be like this and we’ll end right here.”
Destin - “That’s a victor Sierra.”
Justin - “Thats a victor sierra search pattern. So we’ll start this way and then it just goes all the way around. On paper, it looks like we’re going to end up in the same spot, but you’ll see on the chart plotter here in a minute, it’s not going to look anything like this when we get done. Well, try.”
Destin - “How do you how do you command the boat to do that? Are you saying I’m going to run for a certain amount of time and a certain?”
Justin - “Yeah, so we go a certain speed for a certain amount of time. So we’ll run six knots for one minute.”
Destin - “And it will take you how far? point one miles.”
Destin - “OK. Got it.”
Justin - “When I start, I’ll set a waypoint and now there’s a waypoint on our position.”
Destin - “Uh huh. So it’s the other way and it’s a waypoint on position. When I finish, I’ll set another waypoint and I’ll use the distance and the direction to determine set and drift and we’ll use that to plug into our precision search pattern. So you get a good search area, figure out the most probable location for that search object.”
Destin - “So how long does it Victor Sierra take?”
Justin - “About nine minutes.”
Destin - “OK!”
Justin - “You have nine legs a minute apiece. The current and the winds can affect that, maybe not a half minutes. And then it’s like eight and a half. But we’re going to try and turn for six knots once we get our speed set. We’ll leave it. We won’t change our speed. We’ll just let the current take us. So this is a search pattern, will. And so it’s a nomograph. And basically, we’ll tell you what courses you need to steer. So we’re going to start out at 200 degrees and that I know Justin is calculating the compass headings using a nomograph, which is a mechanical way to quickly calculate things.Shepard is controlling the speed of the boat and they’re deploying a datum, which is a floating light that blinks, to get the most calculated set and drift. They’re searching into equal pie pieces, which gives them the most efficient way of searching that circle for the PIW person in the water. So there’s two sides of the boat, the port and starboard. I remember Port is on the left because Port has four letters and left has four letters. So with Ortiz looking out the port side and Muchachi looking out the starboard side and shepherd looking out the front, they’re able to cover every point in the pie in a very methodical way. Now this would be pretty simple if they were on land because the land doesn’t float in one direction or another at varying speeds. The center of the circle would stay in the same position in terms of where they are on the surface of the Earth, which means the GPS location of that circle would stay consistent. But on the ocean with the current, the circle will need to move with the current in order to be relevant. And that’s why they drop the datum in the water to give them a way to keep the middle of the search in line with the drift to the water. And they use math to make sure that they’re still cutting the moving Pie pieces up equally as they search to minimize cross drift. They set up the first leg of their search in the direction that the currents flowing as best they can tell.

Shepard then explains what they are looking for - a 40 year old male with a blue shirt. Destin then adds that he is 39, and Justin adds 20 seconds 320. Justin then says to come to starboard, and Shepard adds that they need to look at it. Destin then says he is going to come look. Justin then says he sees the datum off the starboard beam, and Shepard adds that it is 100 yards off the bow. Destin then says it is hard to see in the sun glare.

Justin then explains that it is difficult to see something out in the water, because they are only looking for the part of the human that is up above the water. He then explains that the same human head at a 10th of a mile or 528 feet is more like 47 thousands of an inch.

Shepard then adds that they are not following a course, they are aiming at the datum. Justin then adds that once they pass the datum, they will come to 080. He explains that it is critical to making a Victor Sierra work, as they go out on a compass heading, turn on a compass heading and then head back towards the datum, not on a compass heading. This is critical to making sure that the Victor Sierra moves with the drifting water. I wanted to get a really sweet view from the top of the boat by clamping a GoPro up there, but I turned the GoPro off and feel shame and apologize. We measured the distance between the waypoint we dropped when we started and the waypoint we dropped when we finished, as well as got the course. We drifted 50 feet over the course of nine minutes, which is 0.02 knots. The seas were calm and the Victor Sierra was almost perfect.

We simulated the GPS coordinates of an RBM performing a Victor Sierra in different types of sea drift. The higher the drift rate, the more crazy the pattern looks, as it cuts the pie up with that drifting section of water. This data can be fed back into the sector command and input into the SAR OPS software to have the best chance of releasing other assets that might need to come on scene to help with the search and rescue.

We also discussed other kinds of search patterns, such as an expanding square, parallel search patterns, creep search patterns, and a barrier search. An expanding square is like playing the game snake, where you make 90 degree turns every minute and build a bigger square. Parallel searches search long ways and creep searches search short ways, while a barrier search is used for a river example, where search units sit in one spot and go back and forth to catch anything that comes down the river. Searching for an overdue vessel can involve following a track line or a shoreline search. For a track line, one would search for the vessel in the direction it was last seen heading. For a shoreline search, one would get as close to shore as possible and look for something on the water. The search patterns are often independent of the situation on the ground or in the water, and the Coast Guard is working on a way to send the search patterns directly to the boats, so they don’t have to manually enter every waypoint. In the end, it’s all about working together as a team to accomplish the mission. This episode of Smarter Every Day is sponsored by Brilliant. Brilliant is a really cool app and website that lets you learn through interactive content at your own pace. In this episode, the Coast Guard used probability in a software package called SAR OPS to figure out where survivors might be located in the water. If you’re like me and it’s been a while since you brushed up on probability, Brilliant has tons of interactive modules that’ll help you understand how probability works. You can get a 20% discount on premium membership by going to Brilliant.org/SmarterEveryDay, or you can sign up for free and just start messing around with stuff to see what you think. The whole point of Smarter Every Day is to get smarter every day, and Brilliant helps you do that. So big thanks to Brilliant for sponsoring Smarter Every Day, and to you for supporting the sponsor that makes these videos happen.