The jets are ready, and the flight instructors are waiting, at a new training center in Romania that was created to teach Ukraine’s pilots to fly the F-16 warplane. But there’s a catch: The Ukrainian pilots have yet to arrive, despite declarations last summer that the center would play a crucial role in getting them into the air to defend their country from increasingly deadly Russian strikes, New York Times wrote, Paralel.Az reports.

It’s still unclear when Ukrainian pilots will begin training at the center, at the Fetesti air base in southeast Romania, which NATO allies also are using to get schooled on the fighter jets. But the delay is a window into the confusion and chaos that has confronted the military alliance’s rush to supply the F-16s.

That is not to say that Ukraine’s pilots are not being prepared. Twelve pilots so far — fewer than a full squadron — are expected to be ready to fly F-16s in combat by this summer after 10 months of training in Denmark, Britain and the United States.

But by the time the pilots return to Ukraine, as few as six F-16s will have been delivered out of about 45 of the fighter jets that European allies have promised.

Nevertheless, their highly anticipated arrival over the battlefield will come not a moment too soon. Russia has employed more aggressive air support to gain ground in eastern Ukraine in recent weeks, using its warplanes to send guided glide bombs over long distances into the Ukrainian front lines.

And Ukraine is desperate for more weapons, of any kind, as it runs low on artillery rounds and other ammunition while Republicans in Congress hold up additional American military aid. The F-16s would likely come armed with short- and medium-range missiles and bombs, partially making up for the shortage of ground-based munitions.

“This year, new fighter jets will be in our skies, and we have to make this year an effective one in defending ourselves against Russian guided bombs, Russian aircraft and their missiles,” President Volodymyr Zelensky of Ukraine said on March 1.

Yet officials agreed that much uncertainty remains about when each country will send its jets, how many will be sent, how fast pilots can be trained, and how Ukraine will get enough people who can maintain the planes properly.

By normal standards, the training of Ukraine’s pilots on the sophisticated Western jets has proceeded at lightning speed, compressing years of classroom learning, simulations and flight exercises into months.

Even so, it is moving more slowly than Ukraine or its allies had hoped, as pilots trained on Soviet-era planes and tactics have had to get up to speed on the English language and Western military practices to make effective use of the F-16s.

Denmark’s defense minister, Troels Lund Poulsen, said in an email exchange that the “training is progressing well,” and noted that Ukraine’s pilots were already flying over Danish airspace. But he said their learning curve “ultimately will decide the length of the training.”

Denmark was at the forefront of a European push last spring to provide Ukraine with F-16s. Ukrainian officials who had overcome Western resistance to supplying a long series of advanced weapons — artillery, air defense missiles, tanks — said the fighter jet was the last major weapon their fighters needed to help them prevail.

The Biden administration reluctantly gave in to Ukraine’s demands, allowing allies to provide the F-16s. The jets are produced by Lockheed Martin and are being phased out in some European militaries in favor of newer F-35 warplanes.

But American officials have warned that the F-16s alone would not be decisive in the war, and that, at any rate, the training would take a considerable amount of time.

“There aren’t very many Ukrainian pilots to be able to pilot those aircraft,” Jake Sullivan, the White House national security adviser, told ABC News last month, defending the Biden administration’s delay in approving plans to send F-16s to the war. “It’s not about whether or not F-16s could possibly have been on the battlefield in the spring of last year.”

He said the United States and its allies were now trying to send Ukraine “all of the tools and capabilities that it needs to be able to conduct this fight as rapidly and as efficiently as we possibly can.”

The Ukrainian pilots’ training began last August at Skrydstrup Air Base in southern Denmark, but their deficiencies in language skills and knowledge of Western flying techniques slowed things down. Not until January were the Ukrainian pilots ready to fly, Danish officials said.

Initially, officials said, the Ukrainians were sent to Denmark instead of the training center in Romania because it was not yet open when the pilots were ready to begin. The creation of the center at the Fetesti base was announced last July, at a NATO summit, and in November its instructors began training Romania’s own pilots for that country’s new F-16 squadron.

Last week, combat-ready Romanian and Turkish pilots guided their F-16s in Romanian airspace about 12 miles from the Black Sea, in a mock intercept of a military cargo plane, to demonstrate their ability to protect NATO air space. Later, they streaked across the sky in dramatic swooping maneuvers, showing off for journalists assembled at the Fetesti base below.

Like the Ukrainian pilots, Romanian trainees at the base were skilled at flying Soviet- and Russian-made jets when they began the Western courses in November. But unlike the Ukrainians, Romania’s pilots already spoke English and were familiar with NATO operating standards.

“So the transition for us wasn’t really all that difficult,” said one of the Romanian pilots being trained, a major who would identify himself only by his call sign, Red. “And we’re just excited to continue flying.”

The next class of eight Ukrainian pilots is scheduled to arrive in Denmark at the end of the summer, but it is not clear when any of them will begin training at Fetesti.

“That’s up to the governments and the contracts that support all that,” said Col. Bill Thomas, a retired U.S. Air Force officer who is overseeing a Lockheed Martin training program for the Romanian pilots at the Fetesti base. “We’re still waiting on all the approvals.”

Then there is the matter of the F-16s themselves.

So far, Denmark, the Netherlands, Norway, and Belgium have committed to sending about 45 of the jets to Ukraine, enough for three small squadrons. Denmark is sending the first six in the late spring, with 13 more due to arrive over the rest of the year and into 2025.

The other countries have not set a delivery date for their F-16s. The Netherlands, which has pledged 24, will hold on to them until Ukraine is ready to receive them, said Jurriaan Esser, a spokesman for the Dutch Defense Ministry.

About 50 Ukrainian technicians are being trained in Denmark to support and repair the jets and handle their weapons packages, given that the F-16 is so complex that it generally takes eight to 14 people to maintain each one. Officials said Western defense contractors would have to accompany the jets into Ukraine, and remain with them, until there were enough Ukrainian crews to maintain them properly — a process that could take years.

And the need to repair Ukraine’s aging and war-damaged military runways could further delay the F-16s’ entry into the war.

As anxious as Ukraine’s leaders are to send F-16s into battle, they are at least as eager to get their hands on more artillery and munitions that are crucial for the ground war against Russia.

“I don’t think F-16s, to themselves, will be a game changer, due to the technical characteristics and number of F-16 teams that are coming,” said Yevgeniya Gaber, a former Ukrainian diplomat and foreign policy adviser.

“But I think together with other ammo and long-range missiles, they will be,” said Ms. Gaber, now a professor at the George C. Marshall Center, a national security academy backed by the German and American governments.

Mr. Poulsen, the Danish defense minister, sees the F-16s as not only supporting Ukraine but, by extension, ensuring security across Europe.

“I strongly believe that Ukraine’s fight for freedom is our fight for freedom,” he said, “and that is why Denmark continues to help Ukraine as much as possible.”