Part 7/11:
As they climbed to higher altitudes with no reliable instrumentation, the pilots began to devise a plan for landing back at Brisbane. Their troubles compounded when they decided to disable the air data computers—a dangerous, irreversible decision that also opened up a critical lifeline: the bus or backup speed system was activated. This technology, not reliant on the blocked pitot tubes, provided a visual representation of the aircraft's speed, allowing the pilots to operate within a safer range during their challenging approach back to the airport.