92 Ill. Adm. Code 14.730
Obstructions
Section 14.730 Obstructions
In order for an RLA to be eligible for a Certificate of
Approval under this Part, an RLA must initially and continually be free of
obstructions (e.g., trees, power lines) on all runways or landing strips within
the glide ratio and height limitations shown in Appendix E, Illustrations A and
C.