Correct

声呐

/ shēng nà / 
Strokes

Definition

sonar

Example

As a Noun

sonar (sound navigation and ranging)

1
Chénchuán
沉船
cánhái
残骸
de
的
wèizhi
位置
kěyòng
可用
shēngnà
声呐
tàncè
探测
  
。

The wreck of a sunken ship can be located by sonar.