Date: 201907
Local time of day: 1801-2400
Location: ORD.Airport, IL
Light: Night
Aircraft: Large Transport; Low Wing; 2 Turbojet Eng
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground ORD
Second aircraft: Large Transport; Low Wing; 2 Turbojet Eng
Reporter organization: Government
Reporter function: Ground
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Situational Awareness
Second reporter function: Ground
Anomaly: Conflict Ground Conflict; Critical; Ground Event / Encounter Ground Strike - Aircraft
Detector: Person Flight Crew
When detected: Taxi
Result: Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification; General Flight Cancelled / Delayed
Contributing factors: Aircraft; Human Factors
Primary problem: Human Factors

Narrative: I was working OGC (Outbound Ground Control). Heavy volume on both OGC and IGC (Inbound Ground Control) due to earlier thunderstorms with the airlines trying to catch up to their normal schedule. Aircraft Y requested taxi from Gate X to Runway 28R-N5. I taxied him [directions] to hold short of A10. A few minutes after taxi IGC told me that Aircraft X; who was pushing from Gate Y; believed that Aircraft Y had clipped his wingtip. I parked Aircraft Y on [position] short of N while the issue was investigated; and he later taxied back to the ramp.This facility needs more staffing so that during high volume times supplemental positions can be opened to relieve frequency congestion.


Second narrative: I was working Inbound Ground Control (IGC) during a very busy session; we had a ground delay program in all day and the program had recently ended so it was very busy and almost all arrivals had occupied gates. Gate X called me for pushback.  I had extreme frequency congestion and several airplanes both taxiing and parked; and Outbound Ground Control (OGC) was also very busy; knowing it would be very difficult to coordinate with him and not having much time to spare to coordinate; I looked out the window and saw a natural gap behind Aircraft Z; so I authorized the pushback after Aircraft Z. Since I was so busy; I don't remember how much time passed before I heard someone say stop on the frequency and I asked who needs to stop? Then maybe a few seconds later Aircraft X said he thought Aircraft Y clipped his wing. I have not had an opportunity to review the replay or listen to the tapes; so at this point I don't know if the pushback was delayed at all after Aircraft Z passed; or how much time elapsed between that and the incident.a. At this airport we should not be responsible for gate push backs onto or through one of the busiest taxiways in the world. It's an outdated concept. Over the last year or two IGC has become much more congested with aircraft and frequency congestion. This is partly due to the fact that arrivals landing 27R that have occupied gates used to be much easier for the North Tower to park. Since then we have lost the Tango Pad; the Scenic Pad has become smaller; and the standard taxi route from 27R is not as conducive to parking gate-waits. This all contributes during busy rushes to more aircraft on frequency for IGC. This is the reason we should not have to stop what we are doing to coordinate with another controller; who may be just as busy; to push an aircraft onto taxiway Alpha or Bravo. The following gates should be eliminated or changed so that they don't require stopping the movement area at the world's busiest airport: [Gates listed]b. If we aren't going to change the gates; maybe we can add [gate] to the same memory aid we have for [two gates] to make coordination easier during very busy traffic.


Synopsis: ORD Ground Controllers reported a possible wingtip incident between two air carriers; and referenced the complexity of the movement area as a contributing factor.