What receiver-error information is already recorded?

The 53 selected stretches come from 53 recording files. Saved primary-receiver metadata is available for 53 files. This is an availability audit, not a count of independent flights.

0 files list GST or GBS error-statistics sentences. Presence alone does not establish their interpretation or a usable covariance.

Of 157,070,543 receiver-stream bytes, 151,620,785 were not parsed as NMEA text. Their contents are not identified by this audit; the count does not mean those bytes are raw GNSS measurements or independent accuracy estimates.

NMEA is a receiver text-message format. GGA provides positions and quality fields; its presence does not supply an independently measured noise covariance. The type codes above are recorded identifiers, not manufacturer or physical-unit identifications.

The audit reads saved inspection records only. It reads no original IMU file, uses no model residuals or fused-navigation covariance, and performs no predictions or fits. Missing or unparsed information remains unknown. The aircraft prediction error law remains unqualified.

Frozen scope · Error assumptions · Roadmap