Complex sentence: During its first flight, "WG760" had unknowingly exceeded, due to position error the Mach meter only showed a maximum of, the occurrence was noticed during flight data analysis a few days later.
Split into simpler sentences: During its first flight, "WG760" had unknowingly exceeded, but due to position error the Mach meter only showed a maximum of. The occurrence was noticed during flight data analysis a few days later.