TITLE: On the Steiner System S(4,5,11)
QUESTION [11 upvotes]: Is there a nice way to partition the edges of the complete 5-uniform hypergraph
on 11 vertices into 7 copies of the Steiner system S(4,5,11)?  If this is
obvious or elementary, I apologize in advance.

REPLY [11 votes]: Unfortunately, no. It is known that the maximum number of mutually disjoint $S(4,5,11)$s on the same point set is $2$. Any such pair are always isomorphic. So, you can't find $7$ disjoint copies of an $S(4,5,11)$ in the complete $5$-uniform hypergraph on $11$ vertices (or partition it into copies); you can find only two of them at most.
E. S. Kramer, D. M. Mesner, Intersections among Steiner systems, J. Combin. Theory, Ser. A, 16 (1974), 273–285