The DeKalb Taylor Municipal Airport re-opened Thursday to limited traffic after being closed since the attacks on the World Trade Center in New York City and the Pentagon.

“All Part 91 (general aviation) aircraft will be permitted to fly IFR (Instrument Flight Rules) only. Clearances must be given on the ground (no airborne clearances will be given),” a city of DeKalb press release said, adding that no flights using visual flight rules will be allowed.

Instrument Flight Rules are rules that the Federal Aviation Administration uses to conduct instrument flight. Visual Flight Rules are rules that are used to conduct flights under visual conditions, including inclement weather.

The FAA also has advised all persons who either operate, service or rent small aircraft to look for suspicious things, such as people who want to rent a plane without proper aviation credentials and people who appear to be loitering in the vicinity of a parked aircraft.