Sonobuoy
（重定向自Sonar buoy）
![Sonobuoy being loaded onto an USN P-3C Orion aircraft](/Images/godic/202502/12/Sonarbuoy_loaded_on_aircraft5817.jpg")
![P-3 Orion paradropping a sonobuoy.](/Images/godic/202502/12/Airlaunched_sonobuoy_1795817.jpg")
![Sonobuoy deployment procedures after impacting water.](/Images/godic/202502/12/Sonobuoy5817.JPG")
![](/Images/godic/202502/12/Akhumps_128_016_0_500c5817.png")
A sonobuoy (a portmanteau of sonar and buoy) is a relatively small buoy (typically 13 cm or 5 in, in diameter and 91 cm or 3 ft long) expendable sonar system that is dropped/ejected from aircraft or ships conducting anti-submarine warfare or underwater acoustic research.