D01 controller described a conflict event when arrival traffic was not transferred from ZDV in a tim...

Narrative:

VFR glider traffic squawking VFR [was] not in communication with ATC circling 10 miles south of tomsn at 17;500 ft. ZDV called to apreq an apa landing aircraft at 19;000 ft and den arrival at 17;000 ft; I approved. Long before these aircraft were on my scope; I noticed the VFR traffic so I called ZDV to give them a friendly 'heads-up'. They said they saw the VFR traffic. A few minutes later air carrier X appears on my scope and the VFR traffic has moved closer to where air carrier X was also heading. Again; I called ZDV to help resolve the situation. I ask for air carrier X at 16;000 ft. They advise that their lowest MVA was 16;400 ft and that they would watch the VFR traffic. Air carrier X was still 10 miles from the VFR and I would have had time to help prevent and accident. ZDV did not ship the aircraft until they were 2 miles apart. I told the aircraft to descend and maneuver at their discretion to avoid a collision. Air carrier X responded to a TCAS RA. The aircraft passed within 0 miles and 200 feet. ZDV did nothing to prevent this near-midair even though I tried several times to prevent the problem. Also; gliders should be asked (on charts) to avoid this area. They are often observed at FL180 but action is not taken because 'their transponders may be off by up to 300 feet.'

Original NASA ASRS Text

Title: D01 Controller described a conflict event when arrival traffic was not transferred from ZDV in a timely manner resulting in a conflict with VFR glider traffic.

Narrative: VFR glider traffic squawking VFR [was] not in communication with ATC circling 10 miles south of TOMSN at 17;500 FT. ZDV called to APREQ an APA landing aircraft at 19;000 FT and DEN arrival at 17;000 FT; I approved. Long before these aircraft were on my scope; I noticed the VFR traffic so I called ZDV to give them a friendly 'heads-up'. They said they saw the VFR traffic. A few minutes later Air Carrier X appears on my scope and the VFR traffic has moved closer to where Air Carrier X was also heading. Again; I called ZDV to help resolve the situation. I ask for Air Carrier X at 16;000 FT. They advise that their lowest MVA was 16;400 FT and that they would watch the VFR traffic. Air Carrier X was still 10 miles from the VFR and I would have had time to help prevent and accident. ZDV did not ship the aircraft until they were 2 miles apart. I told the aircraft to descend and maneuver at their discretion to avoid a collision. Air Carrier X responded to a TCAS RA. The aircraft passed within 0 miles and 200 feet. ZDV did nothing to prevent this near-midair even though I tried several times to prevent the problem. Also; gliders should be asked (on charts) to avoid this area. They are often observed at FL180 but action is not taken because 'their transponders may be off by up to 300 feet.'

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	1050190
Time
Date	201211
Local Time Of Day	0601-1200
Place
Locale Reference	D01.TRACON
State Reference	CO
Aircraft 1
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Aircraft 2
Make Model Name	Sail Plane
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Flight Plan	VFR
Person 1
Function	Departure Approach
Qualification	Air Traffic Control Fully Certified
Events
Anomaly	ATC Issue All Types Conflict NMAC

D01 controller described a conflict event when arrival traffic was not transferred from ZDV in a timely manner resulting in a conflict with VFR glider traffic.