From 1965 the Soviets set a run of world speed and altitude records with the type, flown under the cover designation “Ye-266.” To Western eyes the numbers were terrifying: a machine that could apparently sprint past Mach 3 and climb near the edge of space. Combined with its enormous wing — which analysts read as a sign of tight-turning agility — the intelligence community concluded the USSR had built a Mach-3 air-superiority fighter that would outclass anything America flew.

That assessment shaped a generation of US procurement, feeding directly into the requirement for the F-15 Eagle. The reality — a heavy, steel, straight-line interceptor with a big wing needed simply to carry it at altitude, not to turn — only became undeniable when Belenko’s aircraft was dismantled in 1976. The Foxbat is perhaps the Cold War’s greatest case of an adversary being frightened by a machine that was never what it seemed.

The SR-71 solved the heat problem of sustained supersonic flight with titanium. The Soviets could not: welding titanium reliably was beyond their production base in the 1960s, and the metal was extraordinarily expensive. So Mikoyan-Gurevich built the Foxbat overwhelmingly from a nickel-steel alloy — roughly 80% of its weight — assembled largely by welding, some of it by hand. When Western engineers took Belenko’s jet apart in 1976 they reportedly found rust bleeding through the paint. Steel made the aircraft heavy and thirsty, but it was cheap, robust and could survive the ~300 °C skin temperatures of Mach 2.8 flight.

The most famous demonstration of the Foxbat’s speed — and its limits — came over the Sinai in 1971, when a Soviet-crewed reconnaissance MiG-25 accelerated to Mach 3.2 to outrun an intercepting Israeli F-4 Phantom and its missiles. It escaped clean, but the over-revved engines were ruined and had to be scrapped. That was the deal the airframe offered: it could exceed Mach 3, but only by sacrificing its engines. In everyday service the type was firmly limited to Mach 2.83.

The MiG-25 was a Soviet state product, never sold on an open dollar market, so a firm flyaway unit price simply does not exist in the public record. Period estimates place it in the low single-digit millions of US dollars — very roughly $3–5 million in 1970s–80s terms — but that should be read as an order-of-magnitude guess, not a sourced figure. No credible cost-per-flight-hour number exists for the type in open sources either. Any precise dollar figure you see attached to a MiG-25 is, in practice, an estimate.