Date: 201411
Local time of day: 1801-2400
Location: MDW.Airport, IL
Flight conditions: Mixed
Weather elements / visibility: Icing; 10
Light: Night
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground MDW
Reporter organization: Air Carrier
Reporter function: Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness; Communication Breakdown
Second reporter function: First Officer
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Ground Personnel
When detected: Taxi
Result: Flight Crew Returned To Gate
Contributing factors: Weather; Human Factors
Primary problem: Human Factors

Narrative: Flight Operations reported that we taxied before deice was completed. Deice process underway; First Officer (FO) was communicating with de-ice crew and responded to 'deicing complete' radio call. We both saw a deice truck drive away on the service lane. Multiple deicing events were taking place on same frequency. Performed cross bleed start; called for taxi; cleared left and right; and to follow Company traffic off left.Tower informed us to call Company and return to gate. Company said they needed to re-deice us as it was not complete and that we taxied while deice truck was still spraying. We responded that we acknowledged deicing complete as well as saw a truck drive away. In discussing the incident; the FO and I thought they may have confused tail numbers as the frequency and ramp were very congested. Completed deicing and departed uneventfully. All checklists and FOM/AOM procedures were followed. It is now obvious that we took a similar call sign deicing complete call and assumed that our Crew was clear based on the truck we saw on the service road. Also; the FO cleared the right side for taxi just before the truck came around the corner of the wing. Suggestions for avoiding future miscommunication errors include requiring a visual wave off from Iceman as is required from Pushback Crew and a dedicated frequency per truck so as to avoid other call signs.


Second narrative: Deicing began with 19 minute holdover time. Similar Company tail number communicated with [the de-ice crew] on our frequency and this went unnoticed by Captain and First Officer (FO). Captain communicated to FO concern about duty day. During deice operations; Captain called Scheduling for verification of Crew duty day limitations and FO now had MDW Ground Operations and [the de-ice crew] frequency responsibilities. FO unfamiliar with other Company tail number mistakenly replied for clean aircraft complete; and then switched off or had turned down [the deice] frequency as Captain finished his call with Crew Scheduling. Captain immediately debriefed FO on his call with Scheduling. Captain and FO ensured remainder of checklists are correctly applied as well as non-typical cross bleed start for number two engine (three plus minutes before we moved aircraft). FO communicated with MDW Ground and received ground taxi instructions to 22L. MDW Tower gave initial instructions to position and hold. As we taxi out; Tower told us to clear the runway and contact Ground. Once clear; Ground told us to contact Company operations. Company operations communicates that we almost hit a deice truck. A brief radio discussion occurred and that we were not completely deiced. We complete deice evolution and proceeded to destination.


Synopsis: The flight crew departing MDW inadvertently accepted a 'de-icing complete' transmission intended for another aircraft and had to be recalled prior to takeoff to complete the de-icing process.