MadSci Network: Physics |
Hello Paul,
I found the FAA page you describe, but there's not a lot of information there about this device. I tried web searching on things like 'optical ice sensor' and didn't find anything promising. Then it occurred to me to check the US Patent Office.
There is a patent (number 5760711) for an optical ice sensing device for aircraft; it was granted in June of 1998, so it might be the thing the FAA page refers to. Remember - just because a patent is granted doesn't mean the invention actually works! - but the idea seems to involve firing light pulses at a sensor mounted on the aircraft. If there is a buildup of ice on the sensor more of the light will be reflected into a light detector.
Does it have any limitations? Well, I'm not an an aircraft engineer, but it looks like a pretty rugged system to me. Obviously the fact that the sensor is mounted on the outside of the aircraft means it could be torn off, but I would think that's not an unreasonable limitation. But as I say, I'm not really a good judge - you can read the description for yourself and see what you think.
Again, I don't know if this is the device the FAA document referred to - you best bet would be to ask someone at the FAA directly. But reading the patent description of this device was interesting anyway!
Pauline
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