Date: 201506
Local time of day: 1201-1800
Location: ORD.Airport, IL
Light: Daylight
Aircraft: Regional Jet 700 ER/LR (CRJ700)
Operator: Air Carrier
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground ORD
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Confusion; Situational Awareness
Second reporter function: First Officer; Pilot Not Flying
Anomaly: ATC Issue All Types; Conflict Ground Conflict; Less Severe; Deviation / Discrepancy - Procedural Clearance; Ground Incursion Taxiway
When detected: Taxi
Result: Air Traffic Control Issued New Clearance

Narrative: After landing on runway 9L; the tower gave us a series of taxi instructions that had us taxi down M1; M; M2; cross runway 14L; and then left on U.  On taxiway U we contacted ground control 124.12 who then gave us the instructions to turn right on taxiway G and hold short of the 9R approach area.  My first officer read back the instructions and copied them down on a sheet of paper.  After turning onto taxiway G we were just about to pass taxiway YY when I heard ground control issue us instructions to 'continue; turn left onto taxiway T; hold short of taxiway T7; and contact ground control on point 9.'  My first officer then read back the instructions and wrote it down.  I confirmed it and wrote down /T7 in the FMS scratchpad as a reminder to hold short of T7.  Taxiway G then turns a sharp right and parallels runway 9R; and I observed an aircraft on final for runway 9R that seemed to be around 6 miles out.  Taxiway G then turns to the left and at this point we were approaching a crossing road that had vehicular traffic on it.  I turned my attention to this to make sure we were clear of any vehicles and then turned my attention to taxiway T to make sure we were clear of any taxiing aircraft.  After turning onto taxiway T my First Officer (FO) then contacted ground control on 121.9 stating we were on taxiway T and then gave our assigned gate.  The controller then told us to hold position on taxiway T.  Shortly thereafter I noticed an aircraft that was going around on runway 9R.  The ground controller then cleared us to continue and gave us a number for the tower.  After speaking with a tower supervisor I learned that we had mistakenly entered the 9R approach area and caused an aircraft to go around; and that the FAA would have to review the tapes to see if it was a pilot deviation or controller error.There was a miscommunication between the ground controller and us that may have been influenced by a similar sounding call sign on the frequency.  No correction was given by the ground controller when my first officer read back the clearance to taxi onto T.  My observation that the 9R traffic appeared to be a safe distance after turning onto the section of taxiway G that paralleled runway 9R led to my attention to be diverted to making sure we were clear of vehicular traffic on the roadway that crossed taxiway G near taxiway T and any taxiing aircraft on taxiway T.Many times when we have similar call signs our company will file a different ATC call sign in order to reduce confusion.  Unfortunately in this case we did not have a unique call sign.  The intersection of taxiways G and T is very busy with two taxiways; a vehicular road; and the approach end of 9R.  While marked as a hot spot on the taxiway diagram; it might benefit pilots and controllers if we were required to report holding short of the 9R approach area.  Only after giving this report to the ground controller would we then be cleared to taxi through when landing operations are being conducted on runway 9R.  This would give the controller one last chance to make sure the correct aircraft is proceeding through the area; and it would give the pilots a chance to clear the approach area one last time before having to also divert attention to clearing the vehicular road and taxiway T.  Treating the approach area like crossing a runway in terms of required SOP callouts where both pilots are required to verbally clear the area and state the clearance to enter would also help prevent any further taxi incursions.  Referencing the TCAS display as I approached taxiway T would also have helped accurately judge the distance of the landing traffic and could have led to an additional query to the ground controller as to whether we were really cleared into the approach area.


Second narrative: While inbound on taxiway Golf to the terminal with ground on 124.125 we were given instructions to hold short of the approach end of runway 9 right. As we continued the taxi ground cleared us to continue the taxi via Golf then left on Tango; hold short of Tango 7; and contact ground 121.9. I read back the instruction and the Captain continued the taxi. Once on Tango we saw an aircraft on approach that was going to pass over us. I contacted ground on 121.9 and they told us to hold position. We stopped and the aircraft on final went around. They told us to continue our taxi and gave us a number to call for tower. The captain spoke with ATC over the telephone and they believed that we had read back the clearance that was intended for another aircraft. If this was they case they would have corrected us but there was no correction made over the frequency. I believe the clearance was intended for another aircraft that was also inbound on the same frequency and had a similar call sign. I am certain I read back the correct clearance and ATC may have intended it for another aircraft but accidentally cleared us instead. Generally when aircraft read back a clearance that was intended for another aircraft ATC will correct them and say that the clearance was not for them. To avoid recurring instances such as this it is important that if call signs are similar sounding then ATC as well as pilots need to exercise high caution on the ground and in the air.


Synopsis: After landing a CRJ crew copied a taxi clearance intended for another aircraft and subsequently entered the approach area for an active runway; which necessitated a go-around by an aircraft on final approach.