Show-stoppers in an air traffic control display upgrade

Symptom

Show-stopping defects surfacing during a nationwide upgrade of the software used by air traffic controllers at all U.S. ARTCCs.

Constraint

Fixes needed to be quick, safe, complete, and provable.

Method

Hourly status calls until defect resolved. Log analysis, code analysis, reproduction. Fix, tests covering every branch. Document root cause, analysis, and fix.

Resolution

Show-stoppers closed with a root cause, a fix, and a written rationale, clearing the path for the upgrade to proceed.