Boeing is approaching a critical milestone in the 777X program. According to the latest information, the manufacturer plans to conduct the first test flight in April 2026 of the first production aircraft built in a full commercial configuration. Unlike the four existing test prototypes (WH001–WH004), this aircraft is built entirely in commercial spec, and its first operator will be Lufthansa.
The aircraft is currently in the final preparation phase at Boeing’s Everett Paine Field (PAE) facility. According to local sources and spotter data, fuel system tests are ongoing on the aircraft with line number MSN61535 (LN 1638 / WH128), and ground runs of the GE9X engines are expected to begin very soon. After the certification process is completed, the first two aircraft to be delivered to Lufthansa are expected to be WH003 (N779XY) and WH004 (N779XZ) from the existing prototypes, followed by the first production aircraft joining the fleet.
Launched in 2013, the 777X program is about seven years behind its original schedule due to technical issues and regulatory delays. Boeing is now targeting the first commercial deliveries in 2027. During this long and costly process, Boeing reported program-related losses of $4.9 billion in the third quarter of 2025 alone.
