The Federal Aviation Administration cleared Boeing to resume critical flight-testing phases on its long-delayed 777X wide-body aircraft, advancing the regulatory certification effort that has stretched years beyond the program's original schedule.
Stephanie Pope, chief executive of Boeing Commercial Airplanes, confirmed that the FAA authorized the start of Type Investigation Activities Phase 4B testing on the 777-9 variant. The clearance allows Boeing test crews to complete the remaining envelope expansion and structural load testing required before the FAA can issue a type certificate for the aircraft.
The 777X program has faced multiple setbacks including technical issues with the GE9X engines, supply chain disruptions, and additional FAA scrutiny following safety reviews triggered by previous Boeing incidents. Phase 4B represents one of the final stages in the TIA process, covering specific performance and structural evaluations at the edges of the aircraft's flight envelope.
Boeing has not committed to a revised customer delivery date following the Phase 4B clearance. The 777-9 is designed to carry approximately 426 passengers over ranges up to 7,295 nautical miles. Airlines including Emirates, Qatar Airways, Lufthansa, and US carriers hold orders for the aircraft.
The FAA clearance comes as Boeing works to stabilize production rates on its 737 Max and 787 Dreamliner lines, where the company has been rebuilding quality control processes under ongoing regulatory oversight.
Source: Aviation International News -- https://www.ainonline.com/aviation-news/aerospace/2026-06-08/faa-clears-boeing-start-tia-phase-4b-testing-777x