Task: Question Generation
Input (English): Context : The QF 3-pounder Hotchkiss or in French use Canon Hotchkiss à tir rapide de 47 mm (47mm / L40) was a light 47-mm naval gun introduced in 1886 to defend against new small fast vessels such as torpedo boats, and later submarines. 
Subject : QF 3-pounder Hotchkiss 
Relation : service entry
Output (English): In which year was the service entry date for QF 3-pounder Hotchkiss?