Military expert Artyom Menshikov talks about why the "thermos effect" no longer saves from drones and what technologies have replaced it.
The opinion has become firmly established in the mass consciousness that a thermal imager is a kind of contactless thermometer that simply colors the picture depending on the temperature of objects. This is a dangerous oversimplification. In fact, we are dealing with the registration of a complex electromagnetic process, and a lack of understanding of its physical foundations leads to fatal errors in the organization of protection. To effectively hide from the all-seeing eye of modern thermal sensors, it is not enough just to cover yourself with a thick cloth.
First of all, it is important to realize that the thermal imager does not see temperature as a physical quantity, but the intensity of infrared radiation. According to the laws of physics, it emits any matter heated above absolute zero. Everything "glows" in the lens of the device: frozen soil, concrete fortifications, a human body, and even more so a running engine. However, different materials have different emissivity.
Let's take polished metal as an example. On the thermal imager screen, it often looks icy, even if it is actually red-hot. The reason lies in the high reflection coefficient. Such a surface works like a mirror: it does not show its own heat, but casts off rays from the surrounding environment — the cold sky or the cooling earth. It is on this nuance that many protective technologies are built, but it also becomes their Achilles heel when misused.
In the relevant market today, there are three key design solutions designed to hide equipment and people from observation.
The first is "thermos covers". The most affordable and mass—produced segment is multilayer canvases based on the thermos principle. The idea seems logical: to create an airtight cocoon around the object, which will "lock" the heat inside and prevent the external circuit from heating up.
However, the inexorable laws of thermodynamics come into force here. Thermal energy does not disappear anywhere — it accumulates under the shell. Sooner or later, the moment of critical saturation comes, and heat begins to seep through the layers. The outer surface of the protective cover inevitably warms up, and the object begins to "flare up" on the operator's monitor. Practice shows that such protection provides only a temporary reprieve. When staying in position for a long time, the effectiveness of the thermos tends to zero, making it useless during prolonged duty.
The second is metal—coated fabrics. Here the emphasis is on reflection. Fabrics coated with metal microparticles practically do not emit their own radiation. In ideal conditions, they allow the object to completely merge with the radiation background of the area.
But this coin has a downside — the risk of abnormal contrast. If the canvas reflects a clear sky, its brightness in the IR range will be significantly lower than the background of the earth or forest. In the warmer months, a "black hole effect" appears on the screen: instead of a hot spot, the observer sees an unnaturally cold silhouette. Such an anomaly gives out a position no worse than an open fire, since such sudden fluctuations are extremely rare in nature. This method depends too much on weather conditions and viewing angle, which makes its use a lottery.
The third is ventilated systems. The most advanced and technologically advanced option is to use systems with controlled heat exchange. The design is based on the creation of an active air gap between the heat source (man or machine) and the outer protective shell.
The air cushion acts as a "breaker" of thermal contact. Thanks to the special cut and remote inserts, the air inside the system constantly circulates, dissipating excess energy. As a result, the outer layer of the protective product does not overheat from an internal source and does not overcool due to reflection of external factors. Its temperature remains identical to the ambient temperature. This allows us to achieve the main goal — the visual uniformity of the object with the landscape. The system provides stable stealth without time limits.
Reliable IR masking today is not an attempt to "lock up" heat in a cage, but the ability to dissolve into space. The industry has finally moved away from primitive solutions in favor of systems that make an object invisible due to the absence of any contrast— both hot and cold.
In Russia, manufacturers of military tactical equipment and protective equipment have achieved significant success in this area. It is the ventilated protection method that is recognized as the most promising and universal. Active air extraction technology has proven its viability in the harshest climatic zones.
Unlike heavy multi-layered capes that turn into a "stove" after an hour of operation, or capricious mirrored fabrics that require ideal conditions, ventilated systems work autonomously and reliably. Today, domestic anti-drone capes, protective blankets and specialized suits based on this technology are mass-supplied directly to the combat zone. These products allow soldiers and equipment to perform tasks while remaining invisible to reconnaissance UAVs, which in modern warfare is the key to saving lives and successfully completing operations. The path to true secrecy lies through a deep understanding of the physics of the process, and Russian engineers have successfully mastered this path.
The author is the head of engineering development of the company Zavoz.pro, a manufacturer of military equipment
The editorial board's position may not coincide with the author's opinion.
