A CNN report compiles the testimonies of Ukrainian pilots, as they struggle to contend with the Russian airforce. 

The Ukrainian airforce composed primarily of Soviet-era Su-25s and Mig-29s is dwarfed in challenging Russia's Su-35s with their advanced radars and long-range missiles.

The report contends that one of the primary factors holding back the Ukrainian counteroffensive is Russia's continued air superiority. 

“Our counteroffensive could be much more effective and much safer for our guys on the ground [if we had F-16s], I believe it could be a real game changer for the counter-offensive and for the entire war, because the F-16 is capable of doing a lot of crucial work for our forces, for our resistance,” one Mig-29 pilot said. 

Another pilot estimates that the Ukrainian forces need 12 to 20 F-16 jets to level the playing field but would require around 100 to have a real impact on the outcome of the war.

Back in May, Yuri Sak, an advisor to the Ukrainian defense minister, said Ukraine expects to receive the first F-16 fighters from international donors in the early fall as soon as the United States gives its approval for its allies to deliver their US-made fighter jets to Kiev. 

"I would estimate that end of September, early October, we could see the first F-16s flying in the Ukrainian airspace," Sak said.

According to reports, Congress, US allies, and Ukrainian President Volodymyr Zelensky applied pressure, which led to the provision of fighter jets to Ukraine.

Read more: Biden rules out immediate supply of F-16 fighters to Ukraine: WH

Several NATO allies have offered to train Ukrainian pilots in flying F-16s. US President Joe Biden also told G7 leaders that Washington will endorse supplying advanced warplanes including F-16s to Ukraine and will support efforts to train Kiev's pilots, a senior White House official revealed.

Biden said the United States "will support a joint effort with our allies and partners to train Ukrainian pilots on fourth-generation fighter aircraft, including F-16s, to further strengthen and improve the capabilities of the Ukrainian Air Force," according to the official.

It is worth noting that the Ukrainian President has been desperate for fighter jets, repeatedly pushing for advanced Western jets, but Kiev's international supporters had balked at doing so until recently.

"We have freedom, give us wings to protect it,"  Zelensky told UK Members of Parliament as he toured European countries in the hope of securing fighter jets back in February.

Read more: Selection of pilots for F16 training completed: Ukraine MoD