 Kowang @-@ San would be assaulted during the first phase by 1 KOSB with 1 <unk> and 3 RAR in support , while Maryang San would be taken in the third phase of the operation by 3 RAR and the 1st Battalion , Royal Northumberland Fusiliers ( 1 RNF ) , who were under commander from 29th Brigade for the duration of Operation Commando . <unk> reconnaissance and planning took place in the week prior to the commencement of the operation and Taylor emphasised the use of indirect fires , air support and infiltration tactics to limit casualties , as well as the exploitation of weak points in the Chinese defences . In direct support of the brigade was 16th Field Regiment , Royal New Zealand Artillery with its 3 @.@ 45 @-@ inch ( 88 mm ) 25 @-@ pounder field guns , in addition to divisional and corps assets which included 4 @.@ 2 @-@ inch ( 110 mm ) mortars , 3 @-@ inch ( 76 mm ) howitzers and 155 @-@ millimetre ( 6 @.@ 1 in ) heavy artillery ; in total more than 120 guns and mortars . Also in support were two British Centurion tank squadrons from the 8th Royal Irish Hussars . 
