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Stealth Paint From German Inventor Werner Nickel
Gerhardius writes "Werner Nickel sounds like a Disney-style wacky inventor. He moved to the UAE to develop his previous invention: he had bred a worm whose excrement made it possible to grow radishes in the dry desert sand. That project failed so he moved on to the next item on his agenda, naturally a radar absorbing paint. While it certainly is not unique, there is some interesting history behind the development, and a proposed civilian use."
Except that commercial airports use transponders, not radar, to locate planes.
Don't blame me, I didn't vote for either of them!
Oh, jeez...
The transponders are in the airplanes, not on the airports. They help the airport's radar to see airplanes.
A transponder is a combination of a receiver and a transmitter that receives the pulses from a radar; generates a train of pulses that encode the identification and altitude of the airplane; and transmits them back to the radar. That way the guy sitting at the radar not only sees the airplane more easily, but knows which airplane it is and how high.
rj
If you don't get it, the OP is a reference to Frank Herbert's novel Dune where the chemical produced by the sandwords of the desert planet Arrakis proved the key to faster-than-light travel by giving starship steersmen superhuman powers.
While I admire Herbert's creation of a science fiction novel based on modern studies of desert ecology, I felt the whole spice deal weakened the hard sci-fi goodness of what otherwise would have been a less fantastical book.
That's really not how transponders work. They do not receive the radar pulses and send them back to the radar with ID information encoded into the pulses.
They are totally seperate and unrelated systems operating on radically different frequencies. The only things they have in common is that the base station antenna is typically mounted somewhere on the rotating radar antenna so that they are ensured to both be pointing in the same direction, and they generally share a single display, with the information received from the airborne transponders superimposed over the radar video. You can break either system, and the other one will still work perfectly, just so long as the antenna is still turning and the display still works.
When light hits a surface, it can be reflected, or transmitted. If' it's transmitted then it's going to go through the paint and strike the metal and be reflected.
What are you talking about? Matt Black paint, applied to a mirror, does not result in a surface that reflects visible light.
Paint can certainly absorb photons, and translate the energy to a wavelength no longer recognizable as related to the source.
How did the parent post get rated so highly? Has the Slashdot community fallen so far that it's blinded by the mere mention of "scientific" concepts like index of refraction?
In theory, there's no difference between theory and practice. In practice, there's a big difference.