Eli5: What makes a stealth fighter harder to detect than a regular plane?
In: 284
Generally speaking detection usually involves one of two methods:
– active (bouncing something off a vehicle and detecting its reflection, such as searchlights, radar, sonar).
– passive (detecting disturbance caused by the vehicle, such as noise or heat or magnetic anomalies)
For stealth craft, radar (for long distance detection) and infra-red (for short distance) are the biggest concerns.
Common techniques for avoiding radar:
– build using radar-absorbent materials
– shaped without any sharp, concave ‘corners’ that reflect a lot
– house the powerplants internally behind a long duct (the fans are typically very big reflectors)
– using serrated edges with a mix of absorbent and non-absorbent materials, so the radar bounces back and forth and eventually loses strength.
– house missiles internally in a weapons bay
Reducing Infra-red can be a bit trickier:
– the shape of the nozzle can reduce the signature (slits better than round nozzles)
– some aircraft have the nozzles above the wing, so the hottest part of the exhaust is hidden from ground detection.
– some aircraft mix cold air in with the exhaust in order to cool it to avoid detection.
Latest Answers