"Judah" wrote in message
. ..
If you go back to about 15:10 and set the window to 20 miles you can pick
him up as low as 1600' just south of Yorktown Heights over 134, which I
believe is inside the FARAN intersection, but clearly outside the Outer
Marker - ie: Minimum Safe Altitude is 2000', and he is 400' low...

Just a point of terminology--2000' is the minimum altitude there, but it's
not the MSA. The MSA there is 2900', and wouldn't be relevant. (As is often
the case, the FAA has violated a cardinal rule of clear naming: when two
names are similar, the difference between them should reflect the difference
in their meanings. The MSA differs from the minimum altitude not with regard
to being safe, but with regard to applying when off-course.)

It's tough to say how accurate and to-scale the Passur site is, but if you
set the scale to 5 miles and watch as he enters the area, it would imply
that he passed the Outer Marker at around 1200'...

Maybe he was tracking a harmonic?

Is it possible to pick up a false GS a few hundred feet *below* the proper
altitude?

--Gary