The Boeing 777X program remains one of the most ambitious commercial aircraft efforts of the modern jet age. Combining the long-haul performance of the 777 family with new, state-of-the-art technologies, the 777X is positioned as a flagship aircraft for decades to come. However, despite the anticipation surrounding the aircraft, a longer-than-expected certification process and supply chain delays have pushed the type’s entry into commercial service back by at least seven years.
Yet, despite the delay, Boeing has already produced at least 26 confirmed 777X aircraft, although the actual number is likely higher. With an anticipated delivery date at least a year away, the question of why Boeing has built so many 777Xs before certification remains.
26 777X Aircraft Already Built
According to a report by the Seattle Times, Boeing has already built 26 777X aircraft. Of these, four are currently being used for testing and certification purposes. That leaves a confirmed 22 777X jets that could be ready to be delivered to awaiting airlines soon after the long certification process finally comes to a close. In addition, most of these aircraft are unpainted, aside from the four test aircraft, and remain with a teal fuselage and plain colored airfoils.
However, since The Seattle Times report, Boeing has produced more 777X aircraft. Current satellite data of Boeing Paine Field, about a 30-minute drive north of Seattle and the home of the 777X program, shows at least 32 777X airframes parked at various places around the airfield. This includes planes parked head-to-tail on closed runways, on the ramp just south of the Boeing Future of Flight museum, and even in parking lots north of the airport.
In addition to the aircraft already built and parked at Paine Field, reports state that there is a mix of other 777X aircraft in different stages of production, from early stages of construction to final assembly. This suggests that the number of 777X airframes in post-production storage may increase over the next few months.
Certification Requires Fully-Built 777X Aircraft
As for any commercial airliner, certification, especially in the United States, is heavily reliant on extensive practical flight tests. The FAA requires a lengthy series of ground and flight tests that can only be conducted using fully assembled, production-quality aircraft. These aircraft then become dedicated for the sole purpose of certification, but can also be used for promotional events like the recent Dubai Airshow.
In the case of the 777X, Boeing continues to use its four test frames for static structural testing, evaluation of the GE9X engines, especially important given their large size and thrust levels, systems testing of new avionics and flight controls like the featured folding wingtips, as well as for flight envelope testing to ensure the aircraft performs across all speed, altitude, and attitude scenarios.
In terms of Boeing’s test aircraft, all four were produced between March 2019 and September 2020 and have conducted all of Boeing’s 777X flight tests to date. These aircraft are registered N779XW, N779XX, N779XY, and N779XZ, all referencing 779, the aircraft designation code for the 777-9, the larger of the two 777X variants. The most recent of these aircraft to have flown was N779XW, which performed the first flight of the 777X program in January 2020. According to flight tracking data, on November 25th, N779XW took off from Moses Lake airport in Washington, flew to the Minnesota-Wisconsin border, and returned to Moses Lake. In total, the aircraft was airborne for over eight hours.
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Pre-Built 777X Aircraft Can Avoid Longer Delivery Delays
Other than the four aircraft Boeing has designated for certification purposes, the manufacturer has also built around two dozen 777X planes and placed them in storage. A key reason for the preemptive construction of 777X aircraft is simple: you can’t build a 777 overnight. According to production data from the original 777 family, assembling a widebody Boeing jet takes roughly three months, including mandatory flight testing.
For an aircraft program with global demand, and for a type whose entry into operational service has been delayed by at least seven years, Boeing will want to ensure that its early customers are not forced to wait even longer after an eventual certification because the manufacturer hasn’t produced any aircraft. When Boeing initially anticipated a 2020 certification date, it had already begun building 777X aircraft to address this need.
While at first it may not seem logical to build dozens of uncertified aircraft, major structural changes to the airframe at this stage of the certification process are highly unlikely. This means that Boeing can continue to produce 777X aircraft now, in anticipation of certification, and can expect to make only minor modifications later. Although certification delays pushed Boeing’s launch timeline back by multiple years, having 777X aircraft on hand already could save Boeing weeks, if not months, compared to starting from initial assembly once deliveries begin.
In addition, once FAA certification is received, Boeing plans to ramp up 777X production to a rate of three to five aircraft per month, a substantial amount for the beginning stages of production of a new widebody aircraft. In comparison, Boeing currently produces about seven 787 aircraft per month at its Charleston final assembly line. If Boeing had waited until after certification to begin building the 777X to deliver to customers, it would have been at least three months before the first 777X rolled off the assembly line. Building the over two dozen aircraft currently in storage would have required six additional months.
Oldest 777X Aircraft Won’t Be Delivered First
Although Boeing began 777X production in 2019, the manufacturer recently confirmed that the oldest planes will not be the first to be delivered. At the 2025 Dubai Airshow, Simple Flying’s Tom Boon had the opportunity to speak with Darren Hulst, Vice President of Commercial Marketing at Boeing. In that discussion, Hulst remarked:
“We are producing 777Xs today. In fact, some of the airplanes that we’re building today will be the first to actually deliver because they’re up to the new production standard. Some of the airplanes that we’ve built in the past or have already built will go through some change incorporation to make sure they’re all with the delivery standard or certification standard. And that will kind of feather through the next few years.”
The reason for delivering the newest aircraft first and leaving early-build planes in storage is that initial 777X airframes were constructed to preliminary specifications based on what Boeing expected the certification standard to be at the time. However, as Hulst alluded to, Boeing made small changes over the past five years. These modifications require Boeing’s oldest 777X aircraft to undergo certain upgrades before they can be delivered, while today’s production aircraft are built to the latest standard.
The Oldest 777Xs Are 5 Years Old But Boeing Says They Won’t Be Delivered First
The oldest Boeing 777Xs require modifications before delivery.
Who Will Get The First 777X?
With 777X production continuing and an anticipated delivery date in 2027 (a date that has been continuously pushed back year after year), the question of who will be the recipient of the first 777X remains. Lufthansa is currently expected to be the launch customer. In 2013, Lufthansa was the first airline to order the 777X when it placed an order for 34 777-9s. It later increased its order by seven in May 2022.
However, no matter which airline becomes the launch customer for the 777X, Boeing expects a rapid delivery schedule in the first few months after certification. Speaking on 777X deliveries, Hulst commented, “it is all honestly very, very close together. So between the first operator and the second and the third is only going to be a matter of weeks or months.”
In total, Boeing has over 600 orders for the 777X, with 270 of those from Dubai-based Emirates. In addition to Emirates, Gulf-rival Qatar Airways has orders for 124 777X aircraft. Several Asia-based carriers have also placed significant orders for the 777X, including Korean Air (48), Cathay Pacific (35), Singapore Airlines (31), and All Nippon Airways (20). Altogether, 15 airlines have placed orders for the 777X and are eagerly awaiting delivery of the type.
Continued 777X Certification Delays
The 777X is one of the most highly anticipated and delayed aircraft ever announced. The program has been affected by several rounds of delays, including increased regulatory scrutiny after the 2019 737 MAX crashes, COVID-19-related supply chain disruptions, and extended testing and software review requirements.
These delays have not only significantly impacted Boeing’s financial position but also the strategies of airlines that rely on the 777X for fleet-renewal programs. Among these airlines is Emirates, the largest customer of the 777X. Because of continued delays, Emirates ordered 73 Airbus A350-900 aircraft to support network expansion and the renewal of its legacy 777 fleet.
In addition to Emirates, Lufthansa and Qatar are further examples of airlines forced to alter their strategy because of delivery delays. On the German side, Lufthansa brought several of its A380 aircraft out of retirement and introduced its new Allegris cabin concept on the A350 instead of the 777X. Similar to Qatar, 777X delays forced the airline to bring back its fleet of A380 aircraft to support post-pandemic travel demand.
