See inside a test Boeing 777X, which has flown more than 1,300 hours as the planemaker races to certify its new $442 million jet by 2025
- Boeing's upcoming 777X will be the world's largest twin-engine aircraft when it enters the market.
- The company has been conducting test flights for certification thanks to a family of four experimental planes.
Boeing is building the world's largest two-engine airliner, but it's been a long and difficult road.
In November 2013, the American planemaker announced a brand new commercial jet — the Boeing 777X, which has been broken down into two variants including the 777-8 and the 777-9.
The company also has a freighter option — the 777-8F — that is expected to enter service with Qatar Airways in 2027.
Boeing plans to launch the commercial side first with the 777-9 entering the market in 2025. Emirates will be the launch customer, though the expected timeline has already been delayed from its original 2020 entry.
Challenges surrounding the 737 MAX crashes, the pandemic, and the supply chain have contributed to the slowdown.
Boeing estimates it'll have over $1 billion in abnormal production expenses. And, the manufacturer has faced backlash from airlines — particularly Emirates — for the delays.
Nevertheless, with over 350 orders for the plane, Boeing is standing by the program. It showed off its giant 777X testbed at the Paris Air Show in June — take a look.
Known as Flight Test 1, the 777-9 is one of four 777X test aircraft in Boeing's fleet.
Flight Test 1 has flown more than 1,300 hours across some 540 flights, a flight test engineer told Insider at the airshow.
Each plane has its own purpose, focusing on a spectrum of items like auto-land, environmental testing, low-speed performance, and extended dual-engine range operations.
Boeing builds experimental aircraft to test the limits of the jet and collect data on new technologies — particularly the 777X's folding wingtips.
The testbeds are essential for certification and help Boeing demonstrate to regulators the safety and reliability of its aircraft's technology and engines.
The revolutionary folding mechanism — which is a first in the industry — was introduced to solve the 777X's airport space problem.
The twin-engine airliner will have a wingspan of 235 feet and five inches, which is longer than all previous 777 models.
The 23-foot-longer wings help generate more lift and improve efficiency by 10% compared to predecessors and competing aircraft.
When creating the 777X design, Boeing wanted to ensure the bigger airplane could still fit into the 777-designated airport ramp space.
Each aircraft type has specific airport requirements for everything from the width of the taxiways to the size of the gate, according to the FAA. The above picture shows the space difference between an Air New Zealand Boeing 777 and a Lufthansa Airbus A340.
Boeing wanted to ensure the 777X would not require new infrastructure, saving airports and operators time and money.
But, at the same time, the jet's total wingspan needed to be longer than old 777 models to meet efficiency goals.
A longer wingspan generates more lift, improving performance and decreasing operational costs.
At over 235 feet long, the wings stretched too wide — so Boeing added a system that folds the wingtips up when parked at the gate.
When the wingtips are retracted, the total wingspan is that of older 777 variants at about 212 feet.
A Boeing spokesperson told Insider that despite the novelty of the wingtips, they are safe thanks to redundancies built into the jet.
Boeing experimental test pilot James Hanley told Insider at the Farnborough Airshow in July 2022 that once the plane slows to about 50 knots, the wingtips will fold.
He further explained that because the folding mechanism can't occur until the jet reaches the ground, it's a non-issue in the case of a go-around.
Plus, the wingtips are locked in flight and cannot be manipulated once airborne.
The aircraft is engineered to alert the pilots that wingtips are not extended before takeoff, whether that be via an alarm or auto-throttle not working, for example.
Moreover, the wingtips are part of the pilots' pre-flight checklist — adding another layer of safety.
In addition to the wings, the test aircraft is responsible for evaluating myriad other items, like how the jet performs with heaps of ice on the wing, for example.
It can also access things including how well it can recover from an out-of-control dive or spin, or how it performs flying through rough weather.
To conduct these tests under various conditions, engineers have special systems onboard. One is a series of black water tanks that can manipulate the jet's center of gravity.
The tanks located in the front and aft of the plane allow workers to transfer water back and forth to test the jet under different centers of gravity.
The typical test flight can be around three and a half hours and employees sit at workstations complete with computers and cupholders, according to the Boeing engineer.
Engineers and pilots work together to plan and brief the tests, assessments, and goals for each mission.
Pilots will also relay information to the engineers, like how the systems perform and if there are any human factors concerns, which means how people interact with the machine.
Though, timing can depend on the day's plan and weather conditions.
"If the type of testing is kind of difficult on the body, we won't fly very long," the engineer said. "If it's fuel mileage testing, it's clearly going to be longer."
He further explained to Insider that engineers couple several tests together for efficiency, and that there are typically 10 to 20 people onboard for each mission.
However, there will be fewer people allowed onboard during higher-risk tests, the engineer told Insider.
Also onboard the plane were several rows of cabin seats, as well as a sign that compared the windows to rival Airbus' A350.
The A350 competes with the 777X, but the 777-9 variant is bringing enhancements like bigger windows and more capacity.
Specifically, the 777-9 can fit up to 426 people in a two-class configuration with 10 seats across in economy. Airbus actually changed its A350 design to accommodate 10 abreast rows as a way to better compete with the 777X.
Visitors also got the rare opportunity to see the skeleton of the jet as its wiring and interior systems were exposed.
There were hundreds of feet of wire exposed, as well as insulation systems and other unique components that a typical airline passenger will likely never see.
As Boeing continues in its quest to deliver the first 777X, it plans to operate proving routes in partnership with Emirates next year.
The plan was reported by Leeham News and Analysis in June after speaking with Emirates representatives at the airshow.
The hope is to demonstrate the efficiencies and reliability of the plane to both regulators and Emirates president Tim Clark, who has been skeptical about the jet's entry date.
Clark has been vocal about his frustrations with Boeing over the delayed delivery of the 777X airliner, which he believes could be further pushed to 2026, Leeham News reported.
Currently, the Dubai-based airline has 115 Boeing 777X planes on order — down from the 150-strong purchase the company finalized in 2014.
Clark canceled 35 orders in late 2019, and he has since converted 16 of the 777-8 orders to the 777-9 — the former so far garnering less interest from customers.
In addition to Emirates, several other global airlines also one day hope to own the jet — though none are in the US.
While American Airlines, Delta Air Lines, and United Airlines are still holding off, carriers including Air India, All Nippon Airways, Cathay Pacific, Etihad Airways, Lufthansa, Qatar Airways, and Singapore Airlines are all 777X customers.
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