Rescue victims usually have one thing in common – they want to be found. If able, they will be doing everything they can to signal searchers on the ground and in the air. Occasional exceptions to this are children. They sometimes think they’re going to be in trouble when they’re found, so they hide. If that behavior is suspected it might be more effective to use suspect search techniques, rather than victim search techniques. Let’s evaluate the differences.

A victim’s actions, as rudimentary as they may be, will sharply contrast with that of suspects, who will be doing everything they can to avoid being found. Most airborne law enforcement units in the United States receive extensive training in suspect searches, and they routinely perform those missions. They have technology aboard their aircraft that is very well suited for suspect searches (FLIR, Night Vision Goggles, searchlights, Public Address systems, etc.), but that technology is also effective for victim searches.

Many U.S. airborne law enforcement units have extensive Search and Rescue programs and in some cases SAR missions are prioritized over patrol support. They are usually well trained and equipped to perform SAR missions from beginning to end. Other units often limit their role to searching. Their missions might more accurately be described as Missing Person missions, because the rescue is performed by someone else. The distinction between a Search and Rescue program, and a program that limits its crewmembers to searching, is usually defined by what is done after victims are found. Do we, as a practice, rescue the victims ourselves or do we direct other resources to them? Those are policy decisions that each agency needs to address, but if agencies authorize their crewmembers to perform rescues, it’s crucial that they are properly trained and equipped.

Airborne law enforcement crewmembers that primarily search for suspects, and whose missions do not involve rescues, sometimes assist in searches for victims. But because their role is limited, they often receive no formal training on victim considerations and search techniques. This can lead to protracted and less effective searches, because the techniques that are often effective when searching for suspects, aren’t necessarily the most effective techniques when searching for victims. The goals, abilities and actions of the people we’re looking for should dictate the technology and tactics we use.

For example, if a victim has the ability to signal with a light, NVGs are usually much more effective than FLIR or a stand-alone searchlight. NVGs enable crewmembers to scan large open areas quickly, and spot very faint light sources at significant distances – especially in very dark environments. The backlighting of a cell phone, for example, is usually more than enough light to be detected with NVGs (although the backlighting on my first cell phone was invisible to NVGs). This helps rescuers, because in many cases victims use their cell phones to call for help.

Rescuers can instruct them to point their phones toward the helicopter when they see or hear it. The picture in Figure A was taken through NVGs on a high-illumination night in mountainous terrain. The small light at the top of the mountain is the victim’s cell phone backlight. If the environment was darker, the light would be even more noticeable.

NVGs are also very effective when searching for vehicles that have crashed. We perform these missions on a fairly routine basis, and our aircrews use NVGs and FLIR simultaneously. It’s become almost a competition to see what technology is able to locate the vehicle first. If the vehicle has crashed into thick brush off the side of the road, but its lights are on, NVGs win most of the time. If the lights are off, but the engine compartment or exhaust system are exposed, the FLIR usually spots the vehicle first if it’s still warm. We can enhance the ability of NVGs somewhat by using the searchlight’s wide beam to sweep the area. When the light reflects off the vehicle’s reflectors it is easy to see with goggles, even in fairly dense brush.

In one similar example, a 14 year old girl with a new bicycle became lost while riding it at night in a large wooded area near a lake. Her screams were heard by residents on the far side of the lake who then alerted police. Officers were able to communicate with the victim by yelling, but due to the tendency of sound to travel great distances over water at night, they could not see her or pinpoint her location. They were able to relay instructions from the aircrew for her to position her bicycle so the reflector was pointed in the direction of the helicopter (The helicopter had to leave the area so they could communicate). When they returned, the aircrew immediately located the victim about one mile away with NVGs after a single sweep of the area with the searchlight.

It’s not unusual for us to be tasked with searching for someone who is lost in a rural or canyon environment. Occasionally, those people have neither the training nor the ability to signal the aircraft. As futile as it may be, waving their arms and yelling may be the only things they can do. In those cases we’re going to be relying primarily on the FLIR to search. Both crewmembers will be wearing NVGs, but NVGs do not detect heat contrast well enough to see people at any significant distance unless they’re out in the open and moving. Even then it will be difficult to find them with goggles. There’s nothing wrong with the goggles, they’re just not designed to do this. The spectrum in which they’re sensitive (approximately 600 to 950 nanometers), is primarily infrared, but it’s adjacent to the visible-light spectrum – the spectrum we see with the naked eye. The properties of infrared energy in that spectrum are more reflective than emissive – like visible light. This means that our goggles don’t enable us to see a person’s emitted infrared energy – just their reflected infrared energy, which is far more difficult to see.

Our FLIRs, however, are sensitive to infrared energy in either the 3 to 5 or 8 to 12 micron ranges. The properties of infrared energy in those spectrums are different. The energy is more emissive than reflective, which enables us to detect a person’s emitted IR energy better. This is why FLIR is so effective when searching for people who do not have the ability to signal us with a light, or who are hiding in dark environments. Their body heat is acting like an infrared flashlight.
Another common scenario is to search for Alzheimer patients. They usually don’t have the ability to signal us, and (sadly) they often don’t even know they’re lost. Their behavior is anyone’s guess and ranges from walking until they’re unable to walk anymore, or sitting on a bus bench for hours. When we’re tasked with searching for Alzheimer patients in urban environments, the helicopter’s P. A. system is often the most effective tool to use during the daytime and into the early hours of night.

In a well-populated area, it’s almost a certainty that someone has seen the person we’re looking for – they just don’t know it. It’s simply a matter of broadcasting the victim’s name and description, and then telling whoever might have seen them to call the police. The announcements should be short and to the point. If the message takes too long to broadcast, the aircraft might fly out of the area where the message can be heard. The message should be repeated several times in the area where the person was last seen, or is thought to be. This technique is one of the most underrated and un-used methods of searching, but it’s unquestionably one of the most effective techniques for locating people – even suspects in some cases. The alternative is to fly around and limit the number of searchers to whoever is aboard the aircraft. Why limit ourselves if we have the ability to engage thousands of potential witnesses with the P. A. system?

We use this technique extensively when searching for missing children. They, or someone they’re with, usually hear their name being called and run home. It’s so effective that if we get a good description of the missing person, and we’re on scene within an hour of when they were last seen, we have nearly a 100% success rate of finding them. Of course the credit goes to the citizens who saw them and then called the police, but it was the effective use of technology that led to the find. Just remember to make a few P.A. announcements after they’ve been found to let people know they can stop searching.

It’s not unusual for Alzheimer patients to walk places that are off the beaten path. We’ve found them curled up on the ground near foot paths, huddling on the side of steep hillsides and in a variety of other locations. In some cases they were lying in bushes near a foot path, but not on the path. This made them nearly impossible to see from the path.

During a protracted search, or one in which we get called hours later, the aircrew needs to work closely with ground units and get as much information as possible to narrow down the search-area. If it’s late at night, or there aren’t many people out who might have seen the victim, P. A. announcements might not be very effective. Aircrews will have to evaluate each case individually. When a search-area has been established, the aircrew should first focus their efforts on canyons and other areas that are difficult for ground units to access, and the FLIR should be the primary search tool. Ground units usually aren’t able to search those areas as quickly or as thoroughly as the aircrew can with FLIR. We should focus our efforts in areas we are most likely to be effective.
Unless the victim was wearing reflective material, or clothing that contrasted with the environment, searching with only a searchlight will not be as effective as FLIR. The reason is simple – we’re looking for contrast – contrast between the person and their surroundings. When we’re using a searchlight, we’re relying on a fairly narrow beam of light to reflect off the victim’s clothing and be detected by our eyes. If the victim’s clothing is not high-contrast, if they’re partially concealed by brush, or if they’re outside the searchlight’s beam, it’s going to be very difficult for us to see them.

The FLIR, however, has a much larger field of view and does not rely on reflected infrared energy. Remember? Our FLIRs can detect emitted infrared energy, and people often have relatively high heat emissions when compared to their surroundings. This is why FLIR is so effective when searching in dark environments.

If Search and Rescue is not a unit’s primary mission, but crewmembers occasionally assist on those missions, the unit should consider seeking some specialized training from SAR professionals. The training doesn’t have to be extensive or expensive for it to be beneficial. Basic classroom training on fundamental search techniques could greatly enhance a unit’s abilities to conduct effective searches, and it might expose crewmembers to some techniques they haven’t considered.