Why do many modern fighter designs emphasize stealth and sensors instead of maximum speed?

Modern fighter design has shifted away from prioritizing raw maximum speed because contemporary air combat doctrine emphasizes survivability and information dominance over velocity. While mid-20th-century fighters focused on high-speed performance, 21st-century aircraft prioritize stealth technology, advanced sensors, and maneuverability.1

Several factors drive this evolution:

• Operational Realities: Supersonic flight accounts for only a tiny fraction of total flight time, as the use of afterburners consumes fuel rapidly, severely limiting combat range. Consequently, military cruising speeds remain subsonic.2
• Stealth Constraints: Achieving a low radar signature often requires unconventional shapes and internal carriage of fuel and ordnance, which can conflict with the aerodynamic requirements for extreme speed. Furthermore, early stealth designs avoided heat-producing afterburners to minimize infrared signatures, rendering them incapable of supersonic flight.34
• Strategic Shift: In modern warfare, the ability to remain undetected and process battlefield information is often more critical than the ability to outrun an opponent. Advanced avionics and sensor suites allow pilots to identify and engage threats before they are detected themselves, rendering the pursuit of higher top speeds less strategically valuable than in previous eras.1