. . "Patrol Helicopter"@en . "The MD-520N is an improvement of the MD-500 series, utilizing a NOTAR (no-tail-rotor) design, which reduces noise considerably, and eliminates the collision risk of exposed rear rotor blades."@en . . "\u2022Two passengers"@en . "\u2022Pilot"@en . "\u2022Gunner"@en . "The MD-520N is an improvement of the MD-500 series, utilizing a NOTAR (no-tail-rotor) design, which reduces noise considerably, and eliminates the collision risk of exposed rear rotor blades."@en . . . . . . . "Patrol Helicopter"@en . . . . .