[NLRS] Aircraft Scatter

[Dr. Gerald N. Johnson]

Some claim that the scatter is less the aircraft than the plume of 
supposed ionized gasses behind it made of combustion products and 
perhaps skin friction electrification.

I just opened DUBUS 4/2013 and it has an article on a European aircraft 
scatter program. I've not yet read it.

I think lots of wind upsets the normal density gradient refraction as do 
layers with different humidities and temperatures. Those winds also mix 
the more normal morning temperature inversions from radiation cooling at 
the surface, and that radiant night time cooling doesn't happen with 
lots of clouds. And when the air is already -20, the radiant cooling 
probably isn't effective at getting the surface cooler.

What we have is the capability of finding more about the boundary layer 
atmosphere than the weather researchers know, just by microwave 
propagation over a collection of paths.

73, Jerry, K0CQ

On 12/14/2013 10:43 AM, Bill Davis wrote:
>
>
>     The dongle based aircraft tracking thread is an interesting one, There are a number of aircraft tracking sites on the net, but they have in some cases a time delayed plot of the aircraft's position. I have at times tried to correlate the AC scatter enhancement on Gary W0GHZ's  signals with limited success.
>
>     On Gary's skeds it is VERY UNUSUAL to NOT see aircraft "effects" on his signals. It seems to be more common on 1296 and then 902. I wouldn't characterize the effects be enhancement, for often there is as much "nulling" of the signal as anything else.
>
>    Recently with the advent of the -20deg temps and low humidity, we have lost our 10GHz path from time to time. My memory may fail me, but I don't recall prior to the last couple of weeks seeing obvious AC enhancement on 10GHz. There has been 3 occasions over the last 2 weeks that Gary has been observed briefly 20db or more above the noise floor via AC scatter. In each case the enhancement did not seem to have obvious doppler. From that I assume the aircraft's path must have been at right angles to path? The enhancement as a result been VERY brief, 5sec or so.
>
>    It will be interesting to look for more favorable aircraft position to increase the signal enhancement period. There are a few flights that look promising. Real time tracking would be certainly more helpful than the current services.
>
>    After Christmas, I will investigate the real time tracking, looks interesting and CHEAP :-)
>
>   Merry Christmas and Happy New Year
>
>
> 73  Bill  K0AWU
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