MickG0105
You are referring to a different BTO standard deviation. Refer to the Bayesian analysis p88.
The Arc 7 BTO SD at 0019:29 is not 30 microseconds, it’s 63 microseconds.
When you factor in the error margins associated with magnetic variation, GDAS temps/winds and satellite data, the flightpath is compliant.
You are talking through your hat! And making a general arsehole of yourself by leaving out the hours:minutes separator ... again.
The BTO error is a factor of the Inmarsat systems' clock inaccuracies together with some margins for altitude (what is being described by BTO is in fact the surface of a sphere centred on the satellite; the arc is where that sphere intersects with a spheroid of nominated altitude above the Earth). Magnetic variation, GDAS temps/winds, etc do not enter into it. You have nominated a location for the aircraft at 00:19:30 UTC that is manifestly incompatible with the data. Same same with your nominated locations for Arcs 5 and 6 - you've got the aircraft in locations that sit outside the margin of error. End of story.