Yes, the B-21 Raider does have control surfaces, but they are designed differently from traditional aircraft, including its predecessor, the B-2 Spirit. While it lacks split rudders, the B-21 employs a set of advanced control surfaces to manage flight dynamics effectively.
Key Features of the B-21's Control Surfaces:
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Trailing-Edge Control Surfaces:
- The B-21 uses multiple trailing-edge control surfaces that act as elevons.
- These control surfaces combine the functions of elevators and ailerons, providing pitch, roll, and some yaw control.
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Yaw Control Without Split Rudders:
- Yaw is managed through a combination of:
- Differential engine thrust, where the engines vary their output to create a yawing moment.
- Asymmetric use of control surfaces, adjusting specific trailing-edge flaps to generate the required forces.
- This approach avoids the need for large, radar-reflective surfaces like traditional vertical stabilizers or split rudders.
- Yaw is managed through a combination of:
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Stealth-Oriented Design:
- The design of the control surfaces minimizes the aircraft's radar cross-section.
- The lack of split rudders and vertical stabilizers reduces surface discontinuities that could reflect radar signals.
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Fly-By-Wire System:
- Advanced fly-by-wire technology integrates control inputs, optimizing the performance of all control surfaces.
- This system ensures the aircraft remains highly stable and maneuverable even in complex flight regimes.
Advantages of This Configuration:
- Improved Stealth: Fewer moving parts and a smoother airframe design contribute to a lower radar cross-section.
- Reduced Mechanical Complexity: Simplified control mechanisms reduce potential points of failure and maintenance needs.
- Enhanced Aerodynamic Efficiency: The optimized placement and use of control surfaces improve overall flight performance.
In summary, while the B-21 lacks split rudders, it still incorporates sophisticated control surfaces designed for stealth, efficiency, and operational effectiveness. These innovations represent the evolution of stealth bomber design.
