92 Ill. Adm. Code 14.530
Obstructions
Section 14.530 Obstructions
In order to be eligible for a Certificate of Approval under
this Part, an airport must initially and continually be free of obstructions
(e.g., buildings, trees, power poles, etc.) on all runway or landing
approach/departure surfaces. Glide ratios and height limitations are shown in
Section 14.Appendix A, Illustrations A and C.