In the reverse thrust system of a high bypass engine, which component is responsible for diverting cold stream air?

• A. Duct chutes
• B. Blocker doors
• C. Nozzle petals
• D. Thrust reverser cascades

Answer: (B)

Blocker doors are responsible for diverting the cold bypass air. In a high bypass engine, reverse thrust uses the bypass (cold) stream and redirects it forward through the thrust reverser cascades to create thrust in the opposite direction. The blocker doors move into the bypass duct to block the normal forward path of bypass air and force it toward the cascades, where it is then directed out front to achieve reversal. The other components don’t perform the actual diversion: nozzle petals shape the hot core exhaust, and thrust reverser cascades are the vanes the air passes through to produce reverse thrust, with duct chutes simply guiding air rather than diverting it.