En route controller described a TCAS RA event between an IFR and VFR aircraft within TRACON's airspa...

Narrative:

I was training on the radar controller position. I accepted a hand off on a dash 8 from approach when the aircraft was leaving 8;000 or 9;000 ft if I remember correctly. Inside of approach's airspace was a VFR aircraft indicating 11;500 MSL of unknown type northbound and in direct conflict with the departing dash 8 flight. The aircraft remained on approach's frequency for a short time before checking on; which I assumed was because approach was issuing the traffic. When the aircraft initially checked on he was climbing out of 10;000 for 12;000. I acknowledged the aircraft and issued a climb clearance to FL190. After the read back from the dash 8 flight I issued the traffic of the VFR northbound at 11;500. The flight responded that they were responding to an RA to which I acknowledged. As soon as the conflict was clear; I advised the aircraft that the traffic had passed behind and was no factor. When asked; the flight stated that approach never issued them any traffic in regards to the VFR aircraft. I believe this could have been avoided had approach issued the traffic to the flight before switching him to center frequency. In hindsight I should have issued the traffic first before any sort of control instruction.

Original NASA ASRS Text

Title: En route Controller described a TCAS RA event between an IFR and VFR aircraft within TRACON's airspace. The IFR was handed off and transferred to the Center; the reporter notes the conflicting traffic should have been issued by the TRACON.

Narrative: I was training on the RADAR controller position. I accepted a hand off on a Dash 8 from Approach when the aircraft was leaving 8;000 or 9;000 FT if I remember correctly. Inside of Approach's airspace was a VFR aircraft indicating 11;500 MSL of unknown type northbound and in direct conflict with the departing Dash 8 flight. The aircraft remained on Approach's frequency for a short time before checking on; which I assumed was because Approach was issuing the traffic. When the aircraft initially checked on he was climbing out of 10;000 for 12;000. I acknowledged the aircraft and issued a climb clearance to FL190. After the read back from the Dash 8 flight I issued the traffic of the VFR northbound at 11;500. The flight responded that they were responding to an RA to which I acknowledged. As soon as the conflict was clear; I advised the aircraft that the traffic had passed behind and was no factor. When asked; the flight stated that Approach never issued them any traffic in regards to the VFR aircraft. I believe this could have been avoided had approach issued the traffic to the flight before switching him to Center frequency. In hindsight I should have issued the traffic first before any sort of control instruction.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	995521
Time
Date	201202
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Aircraft 1
Make Model Name	Dash 8 Series Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Route In Use	None
Flight Plan	VFR
Person 1
Function	Trainee Enroute
Qualification	Air Traffic Control Developmental
Events
Anomaly	ATC Issue All Types Conflict Airborne Conflict Deviation - Procedural Published Material / Policy

En route controller described a TCAS RA event between an IFR and VFR aircraft within TRACON's airspace. The IFR was handed off and transferred to the center; the reporter notes the conflicting traffic should have been issued by the TRACON.