Which statement describes how a mechanical-blockage thrust reverser differs from a cascade-type thrust reverser?

Which statement describes how a mechanical-blockage thrust reverser differs from a cascade-type thrust reverser?

• A. Mechanical-blockage uses cascades to direct air.
• B. Mechanical-blockage uses scoop-shaped doors to block rearward flow and deflect forward; cascade-type uses blocker doors and cascades to direct air forward.
• C. Cascade-type uses scoop-shaped doors to block rearward flow.
• D. There is no functional difference.

Answer: (B)

The main idea here is how the bypass air is redirected when a thrust reverser is deployed. The two designs achieve reverse thrust with different internal paths for the air. In a mechanical-blockage reverser, the moving doors themselves block the rearward flow of the bypass air and their scoop-shaped surfaces deflect that blocked air forward. The air is redirected by the shape and motion of the doors, creating a forward-directed jet that produces reverse thrust. In a cascade-type reverser, the doors open to expose a cascade assembly—the rows of small vanes or cascades. Blocker doors help direct the air into these cascades, where the air is then guided forward through the cascade vanes and out of the nacelle to produce reverse thrust. So the key difference is how the air is steered: direct forward deflection by scoop-shaped doors in the mechanical-blockage type, versus guiding air through cascades after opener blocker doors in the cascade type. The other options aren’t correct because they mix up which feature belongs to each design or claim there’s no difference at all.

The main idea here is how the bypass air is redirected when a thrust reverser is deployed. The two designs achieve reverse thrust with different internal paths for the air.

In a mechanical-blockage reverser, the moving doors themselves block the rearward flow of the bypass air and their scoop-shaped surfaces deflect that blocked air forward. The air is redirected by the shape and motion of the doors, creating a forward-directed jet that produces reverse thrust.

In a cascade-type reverser, the doors open to expose a cascade assembly—the rows of small vanes or cascades. Blocker doors help direct the air into these cascades, where the air is then guided forward through the cascade vanes and out of the nacelle to produce reverse thrust.

So the key difference is how the air is steered: direct forward deflection by scoop-shaped doors in the mechanical-blockage type, versus guiding air through cascades after opener blocker doors in the cascade type.

The other options aren’t correct because they mix up which feature belongs to each design or claim there’s no difference at all.