ff1a1   09:37:42  E 2' 9"  N 3'24"     0
f1a1    09:39:28  E 2' 9"  N 3'24"    -4
f1a2    09:41:33  E 2' 9"  N 3'24"    -5
        09:41:33  E 2' 9"  N 3'24"    -5