KYIV, Ukraine - A first group of six Ukrainian pilots is not expected to complete training on the U.S.-made F-16 before next summer, senior Ukrainian government and military officials said, following a series of delays in the West's instruction program for the sophisticated fighter jet.

The timeline reflects the disconnect between Ukraine's supporters, who envision F-16s as a key tool in the country's long-term defense, and Kyiv, which has desperately requested that the jets reach the battle space as soon as possible, viewing them as critical for the current fight against occupying Russian forces.

President Biden, after denying Ukrainian appeals for the F-16 for more than a year, reversed course in May and said he backed the idea of training Ukrainian pilots on the jets, and supported the transfer of the planes by other countries. Denmark and the Netherlands volunteered to lead a training effort, prompting hopes among officials in Kyiv that the planes would be defending Ukrainian airspace by as early as September.

It was a familiar pattern for Ukraine and its chief military backer, the United States, which has repeatedly declined Ukrainian requests only to relent at a later date.

But after the start of training was pushed back several times, Ukraine will now probably have to endure another year without the fighters, which officials in Kyiv hope will provide a significant military edge amid a slow-going counteroffensive and help better protect civilians against Russia's regular missile and drone strikes.

Now, the Biden administration is for the first time signaling its willingness to conduct the F-16 training on American soil. A U.S. official, who spoke on the condition of anonymity to be candid, said Washington would be prepared to bring the aviators to the United States, where the Air Force trains some 400 F-16 pilots a year, if European capacity proves insufficient to meet Ukrainian demand.

U.S. officials describe a training effort, rather than hobbled by Western foot-dragging as Ukrainian officials charge, that is only slowly getting off the ground because of the complexities of standing up a new international initiative and the challenges Ukraine must face in identifying aviators with the right skills in the midst of an existential fight.

Despite the United States' own far larger training capacity, the Biden administration, in a shift from many of the other initiatives surrounding Western support for Ukraine, appears set on letting European allies lead in the F-16 effort for now at least.

The contrasting narratives underscore the ongoing friction between Kyiv and its supporters about the best way to position Ukraine for success against a far larger, better-armed Russian force. It also highlights divisions among those backers themselves, as a small number of European allies pushes to give Ukraine maximum capabilities for its defense and the Biden administration, by far the largest donor of military gear, cautiously weighs next steps.

Ukraine's commander in chief, Gen. Valery Zaluzhny, has criticized Western partners for expecting Ukrainian forces to conduct a large-scale counteroffensive without modern air power. Without fighter jets like the F-16, Ukrainian officials say, they can't compete in the sky.

Ukrainian soldiers on the front lines have said that low-flying Russian helicopters have been successful in attacking their ground forces in part because Ukraine is unable to threaten them in kind.

Just six pilots, about half a squadron, will go through the first round of training, according to two Ukrainian officials, who spoke on the condition of anonymity to address a sensitive matter. Two other pilots have been identified as reserve candidates.

Though the pilots are already fluent in English, the officials said, they must first attend four months of English lessons in Britain to learn terminology associated with the jets. That instruction will occur along with ground staff who may be less proficient in English because, according to Ukrainian officials, Denmark requested to train entire crews together rather than just the pilots first. Denmark's ministry of defense declined to comment.

That pushes back the start of combat training, which is expected to take six months, to January, the Ukrainian officials said. A second group of about the same size would be ready six months after that, or roughly the end of next year.

"This is called dragging it out," one Ukrainian official said. Both Ukrainian officials said they were reluctant to be too critical of their U.S. and European benefactors for fear of appearing ungrateful. The small number of pilots being trained at one time is because there aren't enough trainers available in the participating European nations for a bigger group, they contend.

U.S. officials put at least part of the delay on Ukraine, saying it had only recently provided a list of pilots ready to be trained in an inaugural cohort. Only eight of 32 pilots given English proficiency exams were assessed as having adequate language skills; the rest would require more instruction, the U.S. official said.

"If the Ukrainians have more pilots that are able to be trained, we certainly would welcome that," he said.

U.S. officials add that most of Ukraine's best pilots are expected to remain in Ukraine, where they are flying sorties in Soviet-developed planes and firing French SCALP and British Storm Shadow missiles.

Brig. Gen. Serhii Holubtsov, aviation chief for Ukraine's air force, told The Washington Post that, in between their sorties, Ukrainian pilots have been taking English classes online for the past year.

"Additional specialized training will be provided to flight and ground personnel on the terminology required for the F-16 training," Holubtsov said. "It was not possible to train pilots and other personnel in Ukraine in this terminology due to the lack of experience in working with such terminology."

He said that because the selected pilots already have a high level of basic English, learning the additional terminology "will not take much time."

The single-engine F-16, which debuted in the 1970s and has been updated repeatedly, has been a prized fighter for American partners worldwide. Roughly 3,000 of the aircraft, which can fly as fast as 1,500 mph, are in operation globally, according to manufacturer Lockheed Martin.

Holubtsov said that F-16s come with a powerful radar, which would allow Ukraine to identify more targets and better counter enemy aircraft, missiles and drones than Ukraine's current fleet of fighter jets, which includes Soviet-era MiG-29s and Su-27s. Ukraine would also be able to deploy United Kingdom-provided Harpoon anti-ship missiles from F-16s - a capability Kyiv does not have currently, Holubtsov said - to target Russia's navy, which regularly launches missiles from the Black Sea.

High-speed, antiradiation missiles, or HARMs, which the United States sent Ukraine last year, would also be launched from F-16s, Holubtsov said. "They are already adapted for use on MiG-29 fighters, but due to the lack of an aiming system, their effectiveness is significantly limited," he said.

Ukraine's existing Soviet jets also have semiactive homing warheads, meaning they must continue flying directly at their target until the missile hits. That makes the mission very dangerous for the pilot, he said.

Even as the Zelensky government clamors for immediate assistance in boosting Ukraine's air power, officials in the United States have articulated a very different vision for the F-16. They describe the aircraft as a tool that, rather than altering the battlefield calculus in Ukraine's current operation in the country's east and south, will play a prominent role in Kyiv's transformation into a well-armed regional power that can effectively deter Russia.

"F-16s are about our long-term commitment to Ukraine and are a capability that won't be relevant to the current counteroffensive," said Brig. Gen. Patrick Ryder, the Pentagon's press secretary. He cited ongoing U.S. security aid since Russia's February 2022 invasion - which now exceeds $40 billion, including missiles, mine-clearing equipment and air defenses - and said the United States would support its allies in attempting to get the F-16 training underway as quickly as possible.

"We fully recognize the tough fight Ukraine is engaged in as they defend their country, which is why we continue to actively provide security assistance vital to the battlefield situation at hand," Ryder said. U.S. officials also note they have provided Ukraine ground-to-air missiles and mobile air-defense systems that can target Russian helicopters, and are working to provide more.

Ukraine has asked allies for fighter jets since the early days of Russia's invasion, but its push did not gain traction until this spring.

"We have always given them what they need just about in time," said Michael Clarke, a visiting professor in the department of war studies at King's College London. "Now we may be giving them what they need, just about too late."

Biden's change of heart in May - after months during which U.S. officials insisted the jets weren't needed at this stage in the fight - came amid intensifying pressure from Ukrainian and European officials and U.S. lawmakers.

At a NATO leaders' summit in July, Danish and Dutch officials announced that nine other countries - Britain, Belgium, Canada, Luxembourg, Norway, Poland, Portugal, Romania and Sweden - were on board and that training would start in August.

Well into August, it is clear that plans are still shaping up. Denmark and the Netherlands are wary of getting into specifics on the scope, scale or timing of the effort.

The Danish Ministry of Defense declined to comment on how long the program would take, or respond to questions about potential delays. The Dutch government is working with Romania on setting up a training center in Romania, but U.S. officials said that will take time.

A spokesman for the Dutch Ministry of Defense, Lt. Col. Mark van de Beek, said details were still being fleshed out. A key challenge, he said, is the shortage of F-16 trainers in Europe. The Netherlands, for instance, is in the process of transitioning to the more advanced F-35 and has switched the focus of its training away from F-16s.

"To train a fighter pilot you also need fighter pilots," Van de Beek said. "That is expensive and a capability that smaller countries don't have much anymore." He stressed that training someone to fly an F-16 in combat is a complex task that must proceed step by step. He compared it to learning to drive a car - "first you need to operate the lights and blinkers" he said, "then, you drive it in a parking lot."

But driving a car in a parking lot - or getting an F-16 in the air for training - does not equip you for battle, he said. The final step will be combat training.

Ukrainian officials have frequently questioned why the United States, with a far larger pool of trainers, doesn't conduct the training at Luke Air Force Base in Arizona. That program lasts seven months.

Ukrainians were trained to operate the U.S.-made Patriot air defense system at an Army base in Oklahoma earlier this year.

It now appears the Biden administration would commit to hosting training at Luke or other American facilities if, once the program is up and running, European nation's training capacity cannot match the flow of Ukrainian pilots. "We're willing to train Ukrainian pilots in the United States if needed and if the number of pilots surpasses what Europe is able to do," the U.S. official said.

U.S. officials also said the administration has said it will move quickly to approve partner nations' transfer of the jets to Ukraine once those deals are ready, as required under U.S. law.

The U.K, which does not fly F-16s, is planning to provide ground training and elementary flight training for Ukrainian pilots, laying the groundwork for the more specialized training spearheaded by the Dutch and Danish governments. A U.K. official said that the British government had offered to train Ukrainian pilots on the Typhoon, a twin-engine fighter flown by the Royal Air Force, but Kyiv opted to pursue the F-16.

Like the United States, the British government sees the F-16s as part of a longer-term effort to develop Ukraine's military might.

Though the combat training for Ukraine's most experienced pilots is expected to take six months, Western allies have proposed a separate track for novices that would require more than two years of training, including English lessons.,

In an illustration of the stakes for Ukraine, Russia on Friday fired four Kinzhal hypersonic missiles at an airfield where pilots who are expected to undergo F-16 training will be based, the Ukrainian government said. Air Force spokesman Yuriy Ignat said Moscow "wanted to drive Ukraine off the prospect of rearmament with the latest Western equipment."

Rauhala reported from Brussels, and Ryan from Washington. The Washington Post's Serhiy Morgunov in Stuttgart, Germany, contributed to this report.

previous coverage

• Pentagon announces new long-term arms deal for Ukraine worth $1.3 billion
• Ukraine’s counteroffensive ‘slow’ and ‘steady’ but not a failure, Milley says

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