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They're making some bizarre assumptions.  Why is the probability of casualty due to rocket hits mainly a function of the hydraulics catching on fire?  Sure, this issue got a lot of attention in 1973, mainly because they hadn't thought about it before, but another one of the driving causes of crew loss and catastrophic tank loss is ammunition fire.  Ammunition compartmentalization is one of the areas where the abrams is clearly superior to peer designs.

 

Likewise, I'm not sure the person writing this report (is this another one of those military reform hatchet jobs?  It kinda smells like it) knows how infra-red imaging works.  Infra-red imagers are coated with magical, uber-expensive materials that only let through the wavelength of IR that the imager is sensitive to.  The range of frequencies of "IR" (which is a largely arbitrary designation based on the wavelength where our eyesight stops working particularly well to the approximate wavelength where things start acting more like radio waves) goes from 430 THz to 300 GHz, whereas visible light goes from 430 to 790 GHz.  You can make meaningful generalizations about the behavior of visible light, since all those wonderful, diverse colors we can see are very, very close to each other in wavelength.  IR is much harder to make generalizations about.

 

So, the fact that the abrams' turbine rejects more waste heat and rejects it at a higher temperature does not mean that it will have a higher infra-red signature to ground-based IR sensors.  Most tank thermal imagers make images like this:

 

TIS_Image_2.jpg

 

Where the people are bright white.

 

You don't need to do too much figuring with Wien's displacement law and black-body peak radiation intensity calculations to figure that a sensor that can pick up the wavelength that a 37C human body is not necessarily going to be too sensitive to 500C AGT-1500 exhaust.

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