The FAA has finally publicized the final ruling to alter the class B airspace over Chicago. The change is based on a variety of reasons but is being made primarily to ensure that airplanes landing at O'Hare using instrument procedures are kept within the class B airspace throughout the approach. The new airspace goes into effect October 21, 2010 with the next batch of chart publications.
Previously, some of the instrument approaches were outside of the class B airspace which went counter to the FAA's new policy. The FAA states that all portions of an instrument approach into a class B airport be fully contained within that airports class B airspace. The final changes expand the airspace to the east and west of the current class B airspace to fully include all sections of instrument approaches into O'Hare Airport (ORD).