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To: servo1969

Someone correct me if I have this wrong, but from what I’ve heard, his statement about “The flight path climbed up precipitously to 45,000 feet, stalled, and then dove down to 25,000 feet ‘til it was recovered” is based on interpolation from primary radar returns only. If the transponder was still on and these altitudes were actually reported via Mode C transponder, then I withdraw any disagreement. But if the captain is basing his comments on data taken from primary radar returns only then it’s extremely flimsy evidence because primary surveillance radar (PSR) only provides distance and bearing information - not elevation.

The source of this data has been given as “China and the US” which, since we don’t have any airports over there, I take to mean China and the “US Military”, which also has more sophisticated radar systems that can provide more precise information (PAR) for ground controlled approaches (GCA). But these radars have a range of 10-20 miles and are used to allow ground controllers to guide approaching aircraft onto a carrier, and it’s implausible to think that one would happen to be looking 5 to 8 miles staight up at exactly the right time.


8 posted on 03/18/2014 12:45:00 PM PDT by bigbob (The best way to get a bad law repealed is to enforce it strictly. Abraham Lincoln)
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To: bigbob

You are absolute correct. The altitude thing is getting way too much attention. It is likely bogus, or at least inaccurate.


18 posted on 03/18/2014 12:54:13 PM PDT by Tzfat
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To: bigbob
How come the erratic pitching of the plane to 45K’ and down to 25K’ and so forth and on per ATC transponder only popping out now? I thought the transponders were turned off after co-pilot said “good night?” Normally pilots would say “good night” or “good day” or “roger, so long” if they sign off from departure control frequency after radar separation to air route traffic control center frequency.
50 posted on 03/18/2014 1:28:03 PM PDT by hamboy
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To: bigbob
But if the captain is basing his comments on data taken from primary radar returns only then it’s extremely flimsy

The captain is merely making a professional judgment call based on his experiences, there is no assertion whatsoever...........

And FWIW, his assessment certainly makes more sense that the rest of the 24/7 crap that is being fed to us by the MSM.......

BUT, maybe we can figure out a way to discredit him too...........

62 posted on 03/18/2014 1:37:31 PM PDT by Hot Tabasco (Was Occam's razor made by Gillette?)
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To: bigbob

Some primary radar provide altitude, either by using a pencil beam (like a fire control radar) or surveillance radar with stacked beams. They transmit a big honking fat fan beam like a conventional surveillance radar and receive on a bunch of beams stacked in elevation. You can use the power ratio of the signal in adjacent beams to estimate elevation angle, and thence calculate height.

The png won’t embed, but look a figure 3 in this presentation:

http://www.radartutorial.eu/06.antennas/an12.en.html

As a practical matter, if the target is low to the horizon, even with a pencil beam, the scatter off the surface adds to the direct return in an unpredictable fashion, making elevation measurements unreliable. From about one beamwidth in elevation up, it’s pretty reliable.


72 posted on 03/18/2014 1:43:49 PM PDT by Lonesome in Massachussets (In the long run, we are all dead.)
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To: bigbob

Any navy aegis or carrier radar in the region (not blocked by earth curvature ~ 16 nm line of sight increasing distance with altitude) would have the radar and transponder data - we normally have a number of capable ships around Singapore and the straits. They track everything they get a return for and will highlight anything without a transponder immediately.

The approach radar you refer to is not what is used for tracking purposes. It is specifically engineered for the launch/approach purpose.

It would be unexpected that there is no tracking data all the way (from the turnoff to whereever it went) and we likely know what really occurred.

The transponder turnoff would have been noted almost immediately and flagged by whoever had the air traffic radar and CIC watch posts - and given the timing they would have been on watch only an hour or so.

Whether we or another country had such a ship in the vicinity (there wasn’t a carrier or LHD in the area, but there is normally an Aegis destroyer or cruiser) is the only question...but given proximity to the such a strategic strait and Singapore I have little doubt there was such a ship in the area. Singapore has a phased array radar on their Formidable class frigates that appears to be similar to earlier aegis variants - whether they actively track the way we do I’m unsure.


179 posted on 03/19/2014 8:35:43 AM PDT by reed13k (For evil to triumph it is only necessary for good men to do nothings)
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