But interesting that nearly 300 metres away, the temperature is still 40 degrees C. At 15 metres from nozzle it is nearly 150 degrees C. That is a lot of IR signature.
Also this has a lot to do with staff safety around those engines. So it must be taken stationary on tarmac. I wonder what values it should give at high altitude.
Shame a similar test is not available for f135 to compare.
We can roughly estimate F-135 values from this.
In the Introduction, it was explained that runways are exposed to very high temperatures during the vertical take-off and landing of F-35B combat aircraft. During a take-off or landing, heat is vertically applied to runways through a single direction and can reach up to 930 °C temperatures with a
heating rate of 85 °C s−1.
In the last few days, I've often written about the F-35B. I have explained that the STOVL concept could not be abandoned and that, hopefully, USMC,
theaviationist.com
The newly released document, hosted on a government building-design resource
site, outlines what base-construction engineers need to do to ensure that
the F-35B’s exhaust does not turn the surface it lands on into an
area-denial weapon. And it’s not trivial. Vertical-landing “pads will be
exposed to 1700 deg. F and high velocity (Mach 1) exhaust,” the report says.
The exhaust will melt asphalt and “is likely to spall the surface of
standard airfield concrete pavements on the first VL.
And lastly, IR recording at near idle thrust. Body of F-35 is dark as expected because it is painted with IR signature supressing paint. On the other hand nozzle is glowing and exhaust plume is a lot more visible.
https://www.reddit.com/r/aviation/comments/uz38e0
