Ka dib dagaalkii, fasalka L wuxuu ku lug lahaa tijaabooyinka qalabka cusub ee torpedo iyo qalabka hydrophone labadaba xeebaha bariga iyo galbeedka ka hor inta aan la joojin 1922 iyo 1923.
Dabcan, nooc ka mid ah jumlada ayaa ah "Ka dib dagaalka, fasalka L wuxuu ku lug lahaa tijaabooyinka loo yaqaan 'torpedoes' iyo qalabka 'hydrophone equipment' ee labada xeeb ee bariga iyo galbeedka ka hor inta aan la hawlgelin 1922 iyo 1923 waxaana loo adeegsaday kootada qashin-qubka Mareykanka ee 1933 sida ku xusan Heshiiska Badda ee London ee xaddidaya hubka badda. "