Is the propeller black?
Yes, the propeller is black.
    src         edge_attr  dst
0     1   to the right of   14
1     1   to the right of   17
2     2    to the left of    6
3     3                of    8
4     4  on the bottom of    8
5     4    to the left of   10
6     4    to the left of    5
7     5    to the left of   10
8     5   to the right of    4
9     6   to the right of    2
10    6                of    8
11    8                of    7
12   10   to the right of    5
13   10   to the right of    4
14   12    to the left of   17
15   12    to the left of   14
16   12    to the left of   15
17   14   to the right of   12
18   14    to the left of    1
19   15   to the right of   12
20   17    to the left of    1
21   17   to the right of   12