Another Western source tells us that more than half of Ukraine’s F-16s are currently in maintenance limbo, and at the current pace of use and maintenance Kiev will exhaust the rest by the end of the year. A Ukrainian air force spokesman declined to comment.

But after 300 hours of flying time, F-16s require what’s known as “phase inspection” to keep the engine, avionics, hydraulics, fuel lines and other systems in working order.
The U.S. awarded Sabena Aerospace Engineering, a Belgian company, a contract of up to some $235.5 million for maintenance of Ukraine’s F-16s, though subcontractors perform some of the work. Phase inspection generally takes two to six weeks in the U.S., but it’s “taking as long as 40 weeks in Belgium,” says retired U.S. Navy Rear Adm. Mark Montgomery.