Boeing said on Sunday it remains on track to deliver two new Air Force One ​jets in 2028, but meeting that target will ‌require additional spending on a program already years behind schedule and billions of dollars over budget.

Boeing was awarded a $3.9 billion contract in ​2018 to build the aircraft, though costs have ​since ballooned to more than $5 billion. The aircraft are ⁠intended to replace the current Air Force One planes, ​which entered service in 1990.

“We’re on track for 2028,” Steve ​Parker, CEO of Defense, Space & Security, told reporters ahead of the Farnborough Airshow in the UK, adding that he expected the first ​aircraft to begin testing next year.

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“I do expect to ​see some cost growth there as we come through and we finish ‌off ⁠the wiring and the structures, as well as finishing up our own certifications.”

In May 2025, the United States accepted a luxury Boeing 747 from Qatar for use as a ​temporary presidential aircraft. ​The jet ⁠has since entered service as a bridge aircraft. Security concerns led President Donald Trump to ​forgo flying the Qatari jet home from Turkey, ​opting ⁠instead to return aboard an older Air Force One.

The Air Force One program involves converting two Boeing 747-8 aircraft into highly ⁠specialized ​jets equipped with advanced communications and ​defensive systems. Even with a 2028 delivery, the program would be running four ​years behind schedule.