Van Helsdingen was awarded his first Military William Order on 11 February 1942, for carrying out attacks against Imperial Japanese Navy (IJN) ships in the Battle of Balikpapan on 23 January. Twenty Buffalo fighters carrying two 50 kg bombs each escorted nine Martin B-10 bombers to attack a fleet of IJN ships in the Makassar Strait. Eight hits were scored on four Japanese ships and one destroyer, sinking two transports, with the Dutch losing one Buffalo.
