STAROKOSTIANTYNIV, Ukraine--Explosions reverberated across the pre-dawn sky as Ukrainian air defences fended off a Russian attack on this small city in western Ukraine, home to an important air base and a frequent target of Moscow's strikes. Hours after the assault, the tidy streets of Starokostiantyniv had returned to a semblance of normality. But the June 27 attack was a stark reminder of the challenges Kyiv faces as it rebuilds its depleted air force and deploys the first U.S.-designed F-16s - fighter aircraft that Russia will be determined to ground or destroy. The first planes are expected to arrive this month, and Ukraine hopes they will boost forces struggling to repel a Russian onslaught along the front line, which includes devastating glide bombs that F-16s could potentially disrupt. Officials have not revealed where the F-16s will be based, but Moscow said after the strike on Starokostiantyniv last Thursday that it had targeted airfields it believed would house them. The air base has come under frequent attack since the first days of Russia's February 2022 invasion, including from drones and hypersonic missiles. Residents of this historic military outpost of around 30,000 people, nicknamed Starkon, in Ukraine's Khmelnytskyi region have learned to adjust to the constant danger. "In short, it's 'fun' to live here," said city official and local culture expert Vasyl Muliar with a wry smile, speaking after the recent attack. A Ukrainian air force spokesman said the strikes presented "certain difficulties" but would not undermine the delivery of F-16s or their use in battle. Separately on Tuesday, Russia's defence ministry said it had destroyed five Ukrainian SU-27 fighter jets at Myrhorod airfield in Poltava region. Ukraine said the claim was exaggerated. Military analysts said the Russians were probably targeting air base infrastructure such as runways and storage facilities to make getting F-16s airborne more difficult, and, when they arrive, the Western jets themselves. The Ukrainian military, which is low on air-defence ammunition, is also likely to be forced to move the prized planes around airfields, said Justin Bronk, of the Royal United Services Institute. "Any ground-based air defence coverage can be saturated if the Russians care enough to fire enough missiles at one target," he said. After last Thursday's attack, Governor Serhiy Tyurin said air defences had destroyed nine targets over his region. Shortly before it, the air force had warned residents that drones were headed toward Starokostiantyniv. Local residents, careful not to divulge what might be considered sensitive military information, described living under the threat of being struck and amid the frequent roar of Ukrainian warplanes in the skies above. Iryna Sapchuk, editor-in-chief of local newspaper Our City, said her parents' home had been hit in a previous raid, damaging the roof and shed. "They found debris from a missile in a cherry tree by the window," she added.