Date: 201507
Local time of day: 1801-2400
Location: IAD.Airport, DC
Light: Night
Aircraft: Medium Transport; Low Wing; 2 Turbojet Eng
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Tower IAD
Second aircraft: Medium Transport; Low Wing; 2 Turbojet Eng
Reporter organization: Government
Reporter function: Local
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Communication Breakdown; Human-Machine Interface; Situational Awareness; Training / Qualification
Anomaly: ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Detector: Person Air Traffic Control
When detected: In-flight; Taxi
Result: Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented
Contributing factors: Procedure; Company Policy
Primary problem: Company Policy

Narrative: This is a known event reported by the Front Line Manager using a local Aircraft Identification Problems worksheet. The issue is two aircraft with identical call signs operating in the IAD terminal airspace at the same time. This is a frequent occurrence at this airport and usually happens when the inbound arrival flight is delayed and the airline decides to dispatch a second aircraft to continue the outbound flight using the same call sign. National Airspace System computers allow inbound and outbound tracks with the same call signs; but will not allow their data tags to acquire simultaneously on the radar. ASDE-X surface movement radar does allow the display of same call signs. The result has been departures with no data tag at busy times of the day that often causes the TRACON to stop departures while the issue is sorted out. The other result has been two aircraft with the same call sign on the same frequency; sometimes using the same runway.In this scenario; LC3; after having cleared Aircraft Y to land RY 1C; a minute later; cleared Aircraft X to Line-Up-And-Wait RY30. Confused; Aircraft Y (the arrival) responded that he's on final to 1C. Only then did LC3 realize there were two aircraft with the same call sign on frequency. LC3 then had to warn the pilots to pay attention to the runways mentioned in the clearances and modify his phraseology accordingly. Aircraft Y (the departure) data tag did not acquire until 7 miles WSW out of 3300 FT. LC3 did not warn the departure controller about the duplicate ID situation or the untagged track (as per Letter Of Agreement).Two aircraft with identical call signs active in the system in the same airspace/airport environment is unsafe.IAD and PCT have experienced 16 reported occurrences where Regional Carriers have caused this risky situation; Airline A (12); Airline B (3); and Airline C (1). Again; this reflects only those that ATC became aware of and reported.Measures taken by this facility:1) All occurrences reported or observed have been reported. One was a procedural report - targeting the Regionals' dispatch procedure for not catching duplicate call signs.2) Facility MGMT & NATCA have been made aware.3) Local Safety Council received data.4) We have reached out to ATC Liaisons/Dispatch Managers at the specific carriers.5) After continued occurrences; FSDO CMOs received notifications. There has been additional follow-up dialog with POI's.6) The Regional Airline Association was petitioned to lend assistance.Results:One Regional Carrier implemented procedures to recognize the situation and change call signs by replacing a number with an alpha symbol. They offered to help another Regional do the same. Audits reveal that call signs are being changed; however; duplicate call signs continue to occur.One FSDO POI complained that there is no regulation requiring a carrier to prevent duplicate call signs. Therefore; they can take no enforcement action. They asked our Air Traffic Manager to write the CEO of the regional to ask that they try to do better.But the overwhelming reason for duplicate call signs given by the Regionals (and parroted by CMOs) is that they have new dispatchers and they lack the resources that the major carriers have to prevent it.I'm sorry; but this is not an acceptable excuse anymore. For years the FAA has made preventing runway incursions a primary focus. Yet we continue to not hold these Regional Carriers accountable for their dispatch mistakes. It is time for our FAA leadership to take ownership of this issue and find a way to force Carriers to stop creating such a huge safety risk. Please review the attached data. You have my permission to share this report and data as well as my previous submissions on this topic with others.Airlines must be held accountable for educating their dispatchers to change call signs of the outbound leg if the inbound has not yet arrived. If a regulation needs to be made; then let's write one.  Put pressure on the Regional Airline Association to help resolve this. At IAD; this regional carrier flies under Airline D colors. This is an accident waiting to happen. Have Airline D put pressure on Airline A to fix the problem.Elevate this to the Runway Safety Office.




Synopsis: Local Controller reported the same call sign being used for an aircraft on final as well as another aircraft taxiing for takeoff. Reporter states this is an ongoing problem at this facility and causes confusion for the controllers and pilots. Furthermore; the departure aircraft data tag will not acquire on the departure controllers radar display when this occurs. This is distracting and causes confusion for ATC. Contributing to the situation is dispatchers using the same call sign for an outbound aircraft when the aircraft that is supposed to fly that outbound leg is delayed while inbound.