WASHINGTON — The U.S. Air Force is working to decide how best to train Ukraine’s pilots as the embattled nation’s air force looks to modernize.

In comments at the Aspen Security Forum in Colorado on Wednesday, Air Force Secretary Frank Kendall and Chief of Staff Gen. CQ Brown said Ukraine will need to shift its air force away from legacy Russian MiG and Sukhoi fighters and toward more modern Western-made aircraft.

With the supply of Russian spare parts for MiGs cut off, Brown said, Ukraine will have to eventually move to other fighters.

It remains to be seen which platforms make sense, he said, but there are many possibilities — not just U.S.-made fighters such as the F-15 and F-16, but the Eurofighter, Swedish Gripen and French Rafale could also be options for Ukraine’s air force.

“Part of this is understanding where Ukraine wants to go, and how we meet them where they are,” Brown said. “All of our allies and partners have an interest in ensuring Ukraine can provide for its own security.”

Later at Aspen, asked why the U.S. doesn’t give Ukraine some of its aging A-10 Warthogs — which the Air Force has long sought to retire — Kendall said it’s “largely up to Ukraine” to decide the aircraft it wants.

Ukrainian President Volodomyr Zelenskyy has repeatedly said his nation needs more advanced fighters such as F-15s and F-16s.

Although Ukraine is busy dealing with its “right now problem,” Kendall said, alluding to its largely ground-based fight in the Donbas region, it will eventually have to figure out how its future force should look.

“We’ll be open to discussions with them about what their requirements are and how we might be able to satisfy them,” Kendall said.

In March, Kendall shot down suggestions the U.S. could provide A-10s to Ukraine. But at Aspen, he didn’t close the door entirely to providing older aircraft.

“There are a number of international opportunities that are possible there,” Kendall said. “Older U.S. systems are a possibility.”

When Ukraine’s air force has new fighters, Brown said, the U.S. has a responsibility to help train their pilots on how to fly the different air frames.

In an interview with Reuters on the way to Aspen, Brown said the U.S. and allies are weighing options for training Ukrainian pilots in a long-term program to modernize its air force.

During his discussion at Aspen, Brown said his comments in the Reuters interview were meant to highlight steps the U.S. and allies are already taking to train Ukrainian pilots.

He said the Ukrainians’ success fighting Russia over the last several months is in part a sign of the benefits of the last quarter-century of cooperation between the U.S. and Ukrainian militaries.

Their comments came a week after the House passed its version of a National Defense Authorization Act that would provide $100 million to train Ukrainian pilots to fly U.S. aircraft.

Stephen Losey is the air warfare reporter for Defense News. He previously covered leadership and personnel issues at Air Force Times, and the Pentagon, special operations and air warfare at Military.com. He has traveled to the Middle East to cover U.S. Air Force operations.

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