A newly released Air Force plan calls for the service to replace the C-5 and C-17 airlifters with a single airplane type called the Next-Generation Airlifter.
Air Mobility Command says it will start fielding a new strategic airlifter in about 13 years, but expects to have to keep the C-5 and C-17 in service for another 20 and 50 years, respectively. The two existing airlifters are to be replaced on a one-for-one basis, meaning the Air Force plans to buy 274 new large cargo jets over the next five decades.
The timelines were laid out in the Air Force’s new “Airlift Recapitalization Strategy,” which said the Air Force will have to begin fielding the Next-Generation Airlifter (NGAL) by 2038, with initial operational capability in 2041. However, the slow pace of replacing 52 C-5M Super Galaxy and 222 C-17 Globemaster II aircraft with those new airplanes will mean the existing fleets will have to serve until 2045 and 2075, respectively, according to the strategy, which is linked to a new contracting opportunity notice posted on a government website.
To reach those target dates, AMC would have to buy 7.4 NGAL aircraft per year, a relatively slow tempo roughly equivalent to the rate at which the Air Force is acquiring the high-end, next-generation B-21 Raider bomber. By comparison, the USAF is buying 15 KC-46 tankers per year.
With another 50 years of operations, the C-17 will almost certainly need to undergo a service life extension program (SLEP), much like the now-retired C-141 Starlifter. That upgrade included stretching the C-141’s fuselage to allow it to carry more cargo, but USAF officials have consistently said they do not expect to lengthen the C-17’s fuselage in a similar manner. Doing so would incur more risk, testing, and cost than simply replacing key load-bearing members and possibly the aircraft skin. The Air Force has not publicly discussed replacing the C-17’s Pratt & Whitney F117-100 engines.
It’s not clear if the extensive upgrade of the C-5 undertaken in the 2010s will be enough to keep “viable,” as the notice states, until its newly planned retirement date. During that upgrade, which converted all C-5B and some C-5As to C-5M configuration, the engines and avionics were replaced, and the aircraft received structural strengthening. However, the $10 billion, 10-year fleet improvement has so far failed to produce the C-5 aircraft reliability the Air Force was looking for. The service is now pursuing what it calls the “Drive to 55” program, which seeks to raise the C-5’s mission-capable rate of about 48.5 percent to 55 percent. The C-5M upgrade was originally expected to bring the C-5 to a mission-capable rate above 70 percent.
Air Mobility Command directed questions about the airlifter plans to Air Force Materiel Command, which posted the solicitation but did not immediately respond to a query.
The sam.gov solicitation—seeking industry ideas for NGAL and possible SLEP for the C-5 and C-17—was accompanied by a Nov. 18 memo from Brig. Gen. David A. Fazenbaker, AMC director of strategy, plans, requirements and programs.
“Current recapitalization projections require” that the C-5 and C-17 be kept viable for the C-5M “until 2045 and C-17A viability through 2075,” he said.
The NGAL will replace both types “as the next intra-theater platform,” he said.
An “accelerated” analysis of alternatives on how to obtain what the Air Force will need in its NGAL is set for fiscal 2027, Fazenbaker said. The initial deployment of NGAL by fiscal 2038 and IOC by 2041 is predicated on “an uninterrupted acquisition process with consistent funding.” One NGAL will replace one C-5 or C-17 until the entire fleet is retired. The C-5M will be retired first; the switchover to C-17 replacement would likely start around 2048. At that point, the oldest C-17s will be about 55 years old.
“To mitigate risks associated with acquisition delays, funding uncertainties, or technological challenges,” the Air Force will need to invest to keep the C-5 and C-17 operationally viable until “a fully capable replacement is fielded,” which “may require extending the service life and associated Military Type Certificate (MTC) of each platform,” Fazenbaker said.
Air Force leaders have suggested that the next generation of airlifters and tankers will have to have a reduced signature to function in contested airspace; former Air Force Secretary Frank Kendall has said that the traditional tube-and-wing arrangement will not be sufficient.
The Air Force has indicated that it will need a special operations variant of the next airlifter that is capable of stealthily entering contested airspace, and has also signaled that it will consider variants of a single type to perform both the NGAL and Next-Generation Aerial refueling System (NGAS) mission.
The service is investing $235 million, along with the Defense Innovation Unit, in a Blended-Wing-Body technology demonstrator aircraft built by JetZero, which is partnered with Northrop Grumman on the project. The BWB airframe will increase lift, potentially reduce radar cross section and maximize internal volume, while also offering capability on short runways. A first flight is targeted in 2027. The Air Force has avoided saying that the JetZero aircraft, known as the Z4, will be the basis of a future NGAS or NGAL.
Responses to the solicitation are expected on January 30, 2026, and will likely inform the analysis of alternatives for NGAL.
