First and foremost, this is not the first time Washington has made such allegations. Earlier this year, it was reported that other Su-27 aircraft had engaged in "unsafe and unprofessional" attempts to intercept US surveillance planes.
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As far as the Su-27 is concerned, it is worth noting that analyst Bill French wrote in a report last year that the Russian aircraft is superior in technical performance to the most advanced US jet fighter, the F-35.
He quoted US Air Force Intelligence and the Lockheed Martin Company as saying that for each destroyed Su-27 there would be three F-35s obliterated.
In a separate report published by an authoritative UK-based analytical center, Flight International, the authors said that Russia's Sukhoi Su-27 and Su-30 warplanes are among the world's most commonly sold fighting aircraft.
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According to the report, there are 943 fighter jets from the Su-27 and Su-30 families, accounting for six percent of the total number of combat aircraft in the world.
It is a twin-engine fourth generation front-line aircraft with a blended wing and fuselage, and twin tail fins. During airshows, the Su-27 has repeatedly demonstrated exceptional controllability and maneuverability at high angles of attack.
The aircraft is equipped to operate autonomously in combat over hostile territory, in escorting deep-penetration strike aircraft and in the suppression of enemy airfields. The aircraft provides general air defense in cooperation with ground and airborne control stations, according to the website fighter-planes.com.