Tactical Technology
Greetings fellow aircrew and welcome back. I appreciate each of you taking the time to stop by and read my humble thoughts in each issue of HELIOPS. Although I have written about tactical technology on many different occasions, with spring just around the corner, now is as good time as any to do some “spring cleaning.”
Anyone who knows me has heard me often say “a thermal imager is THE superior piece of technology for finding hiding humans.” Notice how I specify hiding humans. As we all know, hiding suspects behave much differently than lost humans. In a search and rescue situation, a lost human WANTS to be found and will often attempt to signal an aircraft or keep themselves in an open area with the best chance of being spotted.
Without knowing it, a hiker lost in the forest instinctively knows and believes in Igor Sikorsky’s famous quote: “If you’re in trouble anywhere in the world, an airplane can fly over and drop you flowers; a helicopter can land and save your life.” Your lost hiker will do anything they are capable of to find some way to signal your aircraft.
However, a hiding suspect will do precisely the opposite. They are maximally interested in concealing themselves totally from view. They have watched enough police videos to know there is a strong probability an aircraft will be utilized in the search for them.
What suspects do not think of is hiding their infrared energy emission, something actually quite difficult to do. One night, I watched a set of burglars try to hide from the helicopter on a building rooftop by covering themselves with a mylar emergency blanket. Although the blanket blocked the infrared energy of their body; their movement, occasional accidental exposure of their foot and wrinkles in the mylar material quickly gave them away. Also, with your understanding of IR, the blanket was so highly reflective the atmosphere was reflecting off it which created so much contrast they might as well not even have used it.
Since this is a public forum, I will not be covering any other specific tactics that could be used to conceal infrared energy (nice try Mr. Burglar reading our forum to learn tactics to use against us!). The purpose of this article is to remind ourselves as to WHY the thermal imager is what gives a TFO the best chance of finding a hiding human who does NOT want to be found. Trust me when I say, “to find a hiding human, your BEST chance will be by utilizing the thermal imager.”
I have gone into depth in other articles about the advantages and disadvantages for NVG and searchlight, but for this column we will focus on IR. I cannot say it enough times: “If you want the best chance to find a hiding human, USE YOUR THERMAL IMAGER!”
Why?
Simply put:
- Humans emit infrared energy
- A thermal imager is specifically designed to detect infrared energy in the wavelengths in which humans emit energy
- A TFO can manually develop an infrared image to exploit the contrast of human energy amongst the background and exposing the suspect.
From a scientific standpoint:
- Humans EMIT a significant amount of IR energy (.92) in 3-5 and 8-10 micron wavelengths
- When searching for a human with a thermal imager, we are looking for EMITTED energy.
- Humans are highly EMISSIVE (as opposed to REFLECTIVE).
- Thermal imagers were designed to detect infrared energy in the 3-5 and 8-10 micron wavelengths.
NVG primarily utilize REFLECTED light to operate. When using NVG to search for a person who wants to be found, that person will often signal the aircraft or be in an open area in which visible light reflects off of their signal mirror, clothing or flashlight they are waving at you. NVG’s love reflected light, but hate emitted energy.
A hiding suspect will not signal the aircraft, probably will not be in an open area, definitely will not wave a visible light device at you and their human skin has very low reflectivity. However, their infrared energy is glowing at full power whether they like it or not.
Your thermal imager, when pointed in the right direction, is perfectly suited for “seeing” the bright light of infrared energy being emitted by the suspect. Think of it this way: Have you ever walked by a trash can that smells horrible? Your nose detected the smell. No other piece of technology aboard your “aircraft” was able to identify the smelly trash can. You selected the appropriate tool (your nose), used it to identify your suspect (the trash can), and directed resources to it (a hose).
Trust me in believing in the Power of Infrared. Your thermal imager, combined with a proficient Tactical Flight Officer, and a properly positioned aircraft, will have the highest probability of finding a hiding human (also works great for SAR!). A successful aircrew will appropriately prioritize, select AND USE a combination of all forms of available technology.
Thanks as always my brothers and sisters! Fly safe!