| Term: |
PERMANENT ECHO |
|---|---|
| Meaning: | Radar signals reflected from fixed objects on the earth's surface; e.g., buildings, towers, terrain. Permanent echoes are distinguished from "ground clutter" by being definable locations rather than large areas. Under certain conditions they may be used to check radar alignment. |
| Previous Term: | PERFORMANCE-BASED NAVIGATION (PBN) [ICAO] |
| Next Term: | PHOTO RECONNAISSANCE |