LJ35 pilot reported a near midair collision with a glider while on approach in the denver area.

Attributes
ACN	781640
Time
Date	200804
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : apa.airport
State Reference	CO
Altitude	msl single value : 10000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : d01.tracon
Operator	common carrier : air taxi
Make Model Name	Learjet 35
Operating Under FAR Part	Part 135
Flight Phase	descent : approach
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : d01.tracon
Operator	general aviation : personal
Make Model Name	Sail Plane
Operating Under FAR Part	Part 91
Person 1
Affiliation	company : air taxi
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : commercial pilot : cfi
Experience	flight time last 90 days : 200 flight time total : 2400 flight time type : 200
ASRS Report	781640
Person 2
Affiliation	other
Function	flight crew : single pilot
Events
Anomaly	conflict : nmac
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Miss Distance	horizontal : 0 vertical : 200
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

We were flying a lear 35 into apa. We were on vectors with den approach. About 20 NM south of apa; at about 10000 ft MSL; we flew about 200-300 ft underneath what appeared to be a glider. No TA's were given by ATC. We reported the near midair collision to the controller.

Original NASA ASRS Text

Title: LJ35 PLT REPORTED A NMAC WITH A GLIDER WHILE ON APCH IN THE DENVER AREA.

Narrative: WE WERE FLYING A LEAR 35 INTO APA. WE WERE ON VECTORS WITH DEN APCH. ABOUT 20 NM S OF APA; AT ABOUT 10000 FT MSL; WE FLEW ABOUT 200-300 FT UNDERNEATH WHAT APPEARED TO BE A GLIDER. NO TA'S WERE GIVEN BY ATC. WE RPTED THE NMAC TO THE CTLR.

Data retrieved from NASA's ASRS site as of May 2009 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.