navtech_id,relation,navtech_id 2,subcalss_of,5 3,subcalss_of,5 4,subcalss_of,5 6,subcalss_of,3 7,subcalss_of,3 8,subcalss_of,3 6,subcalss_of,4 7,subcalss_of,4 8,subcalss_of,4 14,subcalss_of,13 15,subcalss_of,13 16,subcalss_of,13 17,subcalss_of,13 18,subcalss_of,13 19,subcalss_of,13 20,subcalss_of,13 22,subcalss_of,21 23,subcalss_of,21 24,subcalss_of,21 25,subcalss_of,21 27,subcalss_of,26 28,subcalss_of,26 29,subcalss_of,26 30,subcalss_of,26 12,subcalss_of,26 32,subcalss_of,31 33,subcalss_of,31 34,subcalss_of,31 35,subcalss_of,31 36,subcalss_of,31 37,subcalss_of,31 51,subcalss_of,50 52,subcalss_of,50 53,subcalss_of,50