I assume your italic text was PASSUR explaining their system. It states, These “ghost” aircraft are due to radar reflections from the high-rise buildings around the airport, and possibly from terrain and meteorological conditions farther away from YOUR AIRPORT."
This occurred several miles off coast, over open ocean, on what I suspect was a clear day over the Pacific. The signal being emitted from flight AA612 is being picked up by PASSUR cleanly as it makes it's southward turn and continued ascent out of LAX.
At around 12:51:55, a ghost signal, from AA612 is also picked up by several of the receivers collecting data for PASSUR. A 2nd flight AA612 is identified and recorded. But this flight (the ghost) has one difference from the actual flight, it is recorded at 1500ft altitude.
At 12:51:55, this object is recorded at 1500 ft. At 12:52:53, it jumps to 7200ft. At this moment the actual flight AA612 is recorded at 7000ft. At 12:52:27, PASSUR shows orignal selected flight out of LAX at 7300ft.
The flight out of LAX is 8 to 10 miles off coast and a couple miles up, what terrain feature or meteorological condition at the location of this plane is causing PASSUR to register the ghost image?
I'd wager you that you cannot find another ghost plane registered this far out over the Pacific anywhere on PASSUR that same day or even week or month.
Saying that "the transponder signal from flight AA612 is reflecting off a missile or other physical object at or around 1500ft, at 12:52:23 over the Pacific Ocean on Nov 26, 2005" is a far better explanation than a meteorological condition. Especially since there are eye-witness confirmations of the 2nd object, the PILOTS of flight AA612.
I work in the sonar business. It's much easier to track and identify objects in air than it is in salt water oceans and seas. If the pilots say they saw a missile, or rocket, that same day and time, then there is no doubt in my mind that the ghost record is a reflection of the flight AA612 PUSSAR signal emission off the missle that they saw.
If that were the case, than transponder signals would be reflecting off of objects all over the place and it would be impossible for any type of ground based IFF receiver to work. Think about it. If a missile or small aircraft were capable of reflecting AA612's transponder signal, than the PASSUR display would be constantly covered with bogus ghost tracks as aircraft crossed over other aircraft, antennas, buildings etc. If it is possible for IFF transmissions to bounce off of objects as small and as fast moving as a supersonic missile, than the TCAS system used in every commercial aircraft today would never work (or rather would give you almost constant alerts). Having spent many years operating a very powerful and very advanced radar system, I am still surprised how often my radar displays false returns. Even hundreds of miles over the ocean. It doesn't take much of a meteorological disturbance to spoof a radar.
"Especially since there are eye-witness confirmations of the 2nd object, the PILOTS of flight AA612."
Did you read what their eyewitness was? "It looked more like a rocket". That's it. And they were describing its smoke trail.