What kind of aircraft is in front of the towers?
The aircraft is airplanes.
    src        edge_attr  dst
0     1               of    4
1     1  to the right of    9
2     1   to the left of    4
3     1   to the left of    2
4     1  to the right of    7
5     2  to the right of    1
6     2  to the right of   12
7     2  to the right of    8
8     2   to the left of    3
9     2   to the left of   14
10    2               of    8
11    3  to the right of   12
12    3   on the side of    8
13    3  to the right of    2
14    4  to the right of   10
15    4  to the right of   12
16    4  to the right of    8
17    4  to the right of    1
18    5  to the right of    8
19    5  to the right of   12
20    5  to the right of   10
21    5  to the right of   15
22    7   to the left of    1
23    7   to the left of   12
24    8   to the left of    5
25    8      in front of    9
26    8   to the left of    2
27    8   to the left of   15
28    8   to the left of    4
29    8   to the left of   10
30    8   to the left of   12
31    9           behind    8
32    9   to the left of   12
33    9   to the left of    1
34   10   to the left of    5
35   10   to the left of    4
36   10   to the left of   14
37   10   to the left of   15
38   10  to the right of    8
39   11               in    0
40   12  to the right of    7
41   12  to the right of    8
42   12   to the left of    4
43   12   to the left of    3
44   12   to the left of    2
45   12  to the right of    9
46   12   to the left of   15
47   12   to the left of   14
48   12   to the left of    5
49   13           behind    8
50   14  to the right of    2
51   14  to the right of   10
52   14  to the right of   12
53   15  to the right of   12
54   15  to the right of   10
55   15  to the right of    8
56   15   to the left of    5