By Jenny Klochko, ITV News Producer
Ukrainian pilots will be trained using Nato-standard aircraft this summer, it was announced this week, as Ukrainian President Volodymyr Zelenskyy met Rishi Sunak in the UK on Monday.
President Zelenskyy has said Kyiv "can't control the sky", emphasising the importance of the jets for Ukraine's Air Force.
He wants to create a jet coalition with major powers from the European Union (EU) and the UK.
Doing so could have solved several problems in the Ukrainian defence - mainly the modernisation of its air defence and the approximation of understanding and mastering NATO standards by Ukrainian pilots.
The sky above Ukraine is vulnerable right now. On October 10 2022, Russia started the approach of its massive attack.
Initially, it looked like Russia's response to the explosion and damage of the Kerch Bridge in Crimea - the pride of Russian President Vladimir Putin.
However, Ukrainian Defence Intelligence warned in the summer of 2022 that this tactic would be used to destroy the country's energy infrastructure. In December alone, there were 236 attacks.
Since the beginning of May, Kyiv has survived eight massive attacks. Ukrainian Air defence capabilities have been strengthened since the country was given systems, including NASAMS, Patriot and IRIS-t, from Western allies.
But more support is needed as the country's pilots still use the old SU-27 and MIG-29 jets, which have yet to be modernised since their manufacturing, unlike the F-16s.
Consequently, identifying targets, such as Iranian drones, is almost impossible. Pilots believe it is too optimistic to say they can take down every other drone. Usually, it is mission impossible.
To engage in combat with a Russian fighter jet in the air is, among Ukraine's pilots, known as a "kamikaze operation".
Oleksii, a pilot of an SU-27 with the Ukrainian Air Force, has defended Ukraine from the first hours of the invasion.
Speaking to ITV News from an undisclosed location, he explained in simple terms what it looks like to resist Russian fighters in the sky.
He said: "In the opened field, there's a fighter with a sniper rifle and on the opposite side soldier with a gun, and let the battle begin; your guess, who will win?"
F-16 jets have been discussed for some time. Ukraine has asked its Western allies to send help to protect its airspace and assist in the spring counteroffensive.
Yurii Ignat, a spokesperson for the Ukrainian Air Force, explained to ITV News the importance of now being trained by UK instructors, even though Britain does not have any F-16 jets.
He said: "First of all, the young pilots can conduct a basic course on the primary training aircraft and simulators according to the joint NATO training standards.
"And these next-generation pilots will be ready to master any Western combat airframe after such training, including F-16.
"But also, the training for command and control officers, air traffic controllers, and aircraft maintainers would be beneficial; because all NATO air operations are being planned, organised, supported and executed according to the standardised protocols and procedures."
Many experts call the F-16 a "Lego kit" due to its versatility and upgrade potential. The aircraft is famous for its electronic innovations and approachable repairs.
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A Ukrainian fighter pilot, known by the callsign Juice, defended Kyiv on the first days of the invasion and was part of the famous unit dubbed the "Ghosts of Kyiv".
He spoke to ITV News after just finishing his night shift, explaining how vital it is to be trained for the F-16 jet.
"The main disadvantage of our jets against Russian fighters is that we have old radar with limited range of target detection and outdated missiles," he said.
"Russian jets have powerful modern radars with a much greater detection range and advanced missiles.
"So, therefore I need to fly toward the enemy to launch my missile when his missile is already approaching me like a kamikaze. Of course, I don't do it as it is too risky. That's why we cannot resist them at all. We are able only to defend against their fighter jets."
Oleksii, meanwhile, feels enthusiastic about potentially receiving training for the F-16, as it means a different approach to the combat jets and lots more freedom for the pilot in the sky.
He said that US and UK pilots have more freedom and can make their own decisions during the flight.
"According to my experience, British air forces pilot can be in the cockpit and make decisions himself, according to the information he sees on the screens," he added.
"[A] Ukrainian pilot knows his tasks and where he goes before he gets in the aircraft, and their decision-making is minimal. Because our planes do not have those sophisticated systems, we cannot see the whole picture from above."
The F-16 is a multitasking jet. For the pilot, it means that he can hit targets in the air and on the ground by changing a few switches.
Currently, Ukrainian jets can only hit targets in the air or on the ground once they have taken off.
The F-16 is light and cheap to service, and was created not just for the US Air Force, but also for its allies.
Compared to the F-15, it has "simpler" stuffing. Since its creation, the F-16 has been modernised regularly to be fitted with up-to-date combat missions and operations.
Meanwhile, Ukrainian jets have remained the same since their release from the production plant - that is why the aircraft cannot withstand the challenges of the combat missions.
In addition, the F-16 has up to ten different models and is equipped with modern, sophisticated radar Active Electronically Scanned Array and improved GPS, which allows pilots to "see" the target from a distance of up to 370km away.
Experienced combat pilots have told ITV News that they don't need more than six months of training.
For that to become a reality, the pilots will have to commit to an intensive course - during which they will have to practice flying four or five days a week.
Such a time frame should be enough to train a fully prepared squadron of 12 jets, depending on the planes, instructors, and airbases.
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According to the Ukrainian Air Force spokesperson, the coalition of the leading players of the EU - such as France, Italy and Germany - as well as the UK have said Ukrainians need to master the NATO protocol, which is similar to the various aircraft models.
Yurii is confident that training Ukrainian pilots and using the F-16 will be a game changer in the current war.
The F-16 with various weapons and mastered skills by the Ukrainian Air Force will give the advantage of multitasking capabilities in the sky - which Ukraine does not have at this moment.
Yurii said the change is needed for a successful and robust counteroffensive.
"First, we need an advantage in the sky as the jets can fight their air opponents, target the enemy's logistics on the ground, and support our troops," he said.
"Otherwise, the enemy aviation will invade our airspace and attack our infantry. We need F-16 to protect our servicemen and civilians on the ground."