 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.Van Helsdingen was killed on his 35th birthday by an A6M Zero while providing air support to Royal Dutch East Indies Army forces fighting in Lembang with three other Buffalo aircraft on 7 March 1942.