IR, Thermal Question

Discussion in 'General Discussion' started by SLugomist, Apr 4, 2009.


  1. SLugomist

    SLugomist Monkey++

    Does anyone know of ways to defeat IR and/or thermal?

    I read somewhere a while back that GI bdu's had some type of IR protection as long as they weren't washed with certain soaps.

    What about thermal imaging? Like in predator, obviously this won't work, but when Arnold covered himself in mud so the pred. couldn't see him.
     
  2. dragonfly

    dragonfly Monkey+++

    Now that's a darn good question!
    As I understand it, from having used IR in an APC in Germany in 1969-1970,
    There really is not much you can do to avoid the IR, as it is light created from a heat source, aka: those dark red, near black, lights mounted on the vehicles....
    (like trying to avoid being seen by starlight scopes, quite hard to do!)
    As far as the thermal imaging is concerned, "IF" you can assume the same temperature/s as the surrounding area/s, and not move, you'd be able to avoid detection. Not sure, but the movie with Arnie, depicts that, as he uses the cool mud to disguise himself from the thermal detection. Problem would be to keep that mud/water from becoming heated from one's own skin temperatures.
    I'd have to say "IF" you could manage to isolate your body and "perhaps" even your breathing ,(vapors ?), by some material/s, and not become overheated in doing so, you'd be able to defeat the thermal imaging technology.
    There were some 'studies', (not specified), done using an "aluminized bubble wrap" (as is used for insulation) to insulate the human body's heat signature, BUT the aluminum quickly transferred the heat from the body to the wrapping material and quite literally "glowed" in the dark. (Note: the person quickly overheated in this wrapping materila!)
    The material/s used, would have to be able to quench that heat or disguise it by some way of transfering it to a cooling source.
    Having done some thermal imaging in photography, I found that the hardest part was to disguise the head areas of a human body. (we did this in Denver, Colorado to check homes for heat loss and for insulation companies).
    Personally, I'd like to see more information on this subject!
    Bill
     
  3. RouteClearance

    RouteClearance Monkey+++

    There used to be a night desert pattern that would do a half decent job against passive IR/Starlight scopes. As for thermal imagery, that is a technology that is hard if not impossible to defeat, and I know this from watching pred. video feeds for hours on end.
    The main problem with defeating thermal is that it will increase your chances of being spotted by other methods of detection, ie. ground survailance radar, look down/shoot down radar that is now being incorperated in the Predator/Reaper drones and other types of ground attack aircraft.

    The best way to avoid thermal is to simply stay behind or under as much cover and concealment as possible. I lost track of how many local nationals/insurgents that we lost because they simply walked into a date palm groove where the canopy completely concealed them from the predators thermal camera.

    As for the hollywood tricks, well that's why they emanated from hollywood. Mythbuster's did a program on defeating thermal type detectors and alarms using all the hollywood trick's. They all failed.
     
  4. sniper-66

    sniper-66 Monkey+++ Moderator Emeritus Founding Member

    As everyone else has said, other than cover and concealment, the only other way to defeat thermal is outside your control. It is called thermal crossover. It is a phenomena much like a temperature inversion where FLIR doesn't see much of anything very well. If you were to know when thermal crossover occurred, then you could operate a little more freely, but ot worth the chance. So, as said before, use cover and concealment. If an aircraft is using FLIR, find a tree and stay on the back side. Vegetation has to be thick for this to work. Vegetation in winter is of almost no help.
    As for standard passive IR, some of the big things. Don't wear black or near black while in vegetation. All vegetation reflects light. Black is the absorption of all color, so it stands out like a sore thumb in any quantity. Hence why the Army no longer wears black boots. Look at a soldier in Iraq and you won't see much black other than his weapon. Anything that reflects light during the day, will reflect it at night. The more ambient light, the brighter things will be to passive IR. Again, stay in vegetated areas and shadow areas. Make sure that you don't have anything that is producing any level of light, visible or not visible. If you have a radio with any kind of back light, tape it over or shut it off. Just putting it in your pocket will make the light a dull glow instead of a bright light, but it will be visible.
     
  5. SLugomist

    SLugomist Monkey++

    So would you want something to absorb the IR, or thermal, or to have it reflect it? I would think reflecting it would give a bigger signature.
     
  6. QuietOne

    QuietOne Monkey++

    Has anyone tested a water spray? A tarp held away from the body with a light spray of water on it will drop below ambient temperature if the humidity isn't too high. Have to stay totally covered; they will see your face if you peek out.
     
  7. SLugomist

    SLugomist Monkey++

  8. SLugomist

    SLugomist Monkey++

  9. sniper-66

    sniper-66 Monkey+++ Moderator Emeritus Founding Member

    All of these items are cover as we have discussed already. The first thing to remember is that you don't need a fancy dancy high dollar barrier, any barrier will work. Thermal cannot see through glass either. If you use a tarp, you will have to have it away from your body so that the ambient temperature doesn't heat the barrier. Also, I wouldn't cool it down as that will leave a dark spot in comparrison to the surrounding. If you have a square tarp that you spray water on to cool down, then, you will have a darker square, giving away your position. It is best to let the tarp be the same temperature as the surroundings. Also, make it an irregular shape as well.
     
  10. tacmotusn

    tacmotusn RIP 1/13/21

    i also have considered this question. in reading the other posts one thought jumped out at me. if you had a hide with a tarp strung (preferably one of those camo one side/emergency aluminum survival blanket on the other, in an area where watering wouldn't be out of the ordinary (fruit growing area, garden, etc) it just might work. another question though.... is helicopter IFLR omni-directional, or normally directed forward?
     
  11. RouteClearance

    RouteClearance Monkey+++

    As I stated in my first post, using any kind of RADAR reflective materials will only increase your chances of being discovered by other types of technologies, for radar can cover a lot more area than FLIR cameras. Plus those space blankest can be quite noisy while handling and have a mirror finish which you do not want while adhearing to your basic rules of camoflage.

    As stated before, your basic poncho/tarp will be just as effective if you set it up right.
     
  12. SLugomist

    SLugomist Monkey++

    Radar is a shorter wavelength, called microwave.

    IR and Thermal are Infrared , just different ends of the IR spectrum. Just shorter than visible light. Cause heat radiates in the IR spectrum

    My only problem with the COVER solution is that I've seen people through walls with thermal.

    An extremely insulated suit could work for or a liquid cooled "space suit" maybe.

    That flexable sheet, I'm wondering if any one ever put that to a real IR camera or thermal.

    The pic looks neat though.

    Oh is my avatar OK? lol
     
  13. QuietOne

    QuietOne Monkey++

    Sniper-66 said:
    That's what I'm suggesting. Put a tarp over a heat source, like a human body, and in a few minutes an IR imager will pick up the thermal image through the tarp as it warms up. But what if you cooled the tarp with a water spray? Has anyone tried it?

    An irregular outline is always good concealment.
     
  14. WestPointMAG

    WestPointMAG Monkey++

    After the SHTF and early in the PAW IR and thermal devices will be available since they are a necessary part of the well stocked prepper’s equipment load out. So it is important to remember that the BHFs will not be the only ones that will have this kind of technology.
    The most important thing to remember when dealing with IR and thermal detection or detection in general is not to look like a juicy target. Do not have supplies setting out in the open, a lot of above ground traffic, a total absence of aboveground traffic, restrict eating out side, outdoor kitchens should be well screened from prying eyes, everyone should dress down, do not have any voids, do not have armed guards posted where they can be seen, do not plant one big garden, stay alert, keep your eyes open and your mouths shut.

    I am working on an expanded version of this but I am going to post it as a separate thread.
     
  15. sniper-66

    sniper-66 Monkey+++ Moderator Emeritus Founding Member

    You can't have the tarp close to your body, you have to have some distance, or you will heat the tarp up. As for spraying it down, you would have to do it from the inside, probaly not a good option, just keep some distance from the tarp.
    As for helo FLIR, most are on a gimble and can be rotated. Usually co witnessed with the Night Sun light.
     
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