OVERVIEW:  The PERCH GILL aka Tamir-5L/LS is an active, dual-frequency submarine sonar operating in the high sonar frequency band. 

DETAILS:  The Tamir is a searchlight sonar, meaning it can only look in one direction at a time and must swing around to see what is in the other directions area by area. The Tamir was probably copied from UK or German WWII sonars.  

Specifications:
	Frequency: 	15, 24 kHz
	Range:		2.0 nm

			
NOTES:  IOC 1947.  Corresponding surface ship set is the Tamir-5N.


SOURCES: Friedman, The Naval Institute Guide to World Naval Weapons Systems 1997-98, pg. 607 ; "At the forefront of the underwater confrontation: submarine hydroacoustics. From the beginning of the cold war to the 70s." Top War. Last modified August 7, 2020. https://en.topwar.ru/173865-na-ostrie-podvodnogo-protivostojanija-gidroakustika-podlodok-ot-nachala-holodnoj-vojny-do-70-h.html.
