Russia has grounded its A-50 early warning and control planes after losing two of the valuable aircraft within a few weeks, British defense officials have said. Reports that Russian forces have the upper hand on the battlefield in Ukraine, following their capture of Avdiivka in Donetsk oblast, have not been matched by positive assessments of Moscow's air power following a string of reported losses. On February 23, Ukraine's Air Force spoke about the downing of a Russian Beriev A-50U long-range radar-detection aircraft near the Sea of Azov using a Soviet S-200 anti-aircraft system. Russian milbloggers said it was probably hit...