Narrative:

D01 coordinated to bring aircraft X in through the northwest corner of the airspace at 120 to avoid some glider activity around kelly air park (off the LOA). This aircraft was already 5-10 miles from the northwest corner and pointed at cos. Aircraft Y has been doing aerial survey lines VFR extending 15 miles north of cos to 10-15 miles south of cos for several hours at 145 or higher. VFR aircraft Z had an inoperative mode C and was transitioning from somewhere south of publication to apa. Aircraft Z was restricted to 115 due to the inoperative mode C. Other aircraft were in other parts of the airspace as well. Aircraft Y advised that he was finished with his survey lines and was ready to return to base while at 130. I tried to turn him to a heading of 030 to get him out of the arrival corridor for his descent and told him to descend to 110. However; he advised that he was not done with his lines and still had to continue on a line. I told aircraft Y to continue his line; but forgot to advise him stop his descent. Aircraft Y continued north; then turned northwest while descending. I had to issue a vector to aircraft Z to keep him out of the aff airspace; and he requested to descend. I agreed; and then issued traffic. I turned aircraft X to H110 to descend him and avoid the aircraft Z; then realized that aircraft Y had finished his line and started descending--taking a turn I did not anticipate. Aircraft X initiated a TCAS RA for aircraft Y; who was about 1.5 miles south of him. Aircraft Y had aircraft X in sight; but I do not remember if it was before/after the TCAS RA.I was likely fatigued because I was trying to get training for a trainee and took very few breaks to make this happen. I tried to ensure breaks for the other cpc and trainee; at my own expense. In hindsight; this may not have been the best plan with regards to myself. I could have also prevented this if I had required D01 to bring aircraft X in on the LOA--which would have brought him in on the east side of the airspace; long after aircraft Y and aircraft Z.

Related reports:

Google
 

Original NASA ASRS Text

Title: COS Controller reports that due to accepting an aircraft on other then LOA procedure they ended up having an operational error and TCAS RA Event.

Narrative: D01 coordinated to bring Aircraft X in through the NW corner of the airspace at 120 to avoid some glider activity around Kelly Air Park (off the LOA). This aircraft was already 5-10 miles from the NW corner and pointed at COS. Aircraft Y has been doing aerial survey lines VFR extending 15 miles N of COS to 10-15 miles S of COS for several hours at 145 or higher. VFR Aircraft Z had an inoperative Mode C and was transitioning from somewhere south of PUB to APA. Aircraft Z was restricted to 115 due to the inoperative Mode C. Other aircraft were in other parts of the airspace as well. Aircraft Y advised that he was finished with his survey lines and was ready to return to base while at 130. I tried to turn him to a heading of 030 to get him out of the arrival corridor for his descent and told him to descend to 110. However; he advised that he was not done with his lines and still had to continue on a line. I told Aircraft Y to continue his line; but forgot to advise him stop his descent. Aircraft Y continued N; then turned NW while descending. I had to issue a vector to Aircraft Z to keep him out of the AFF airspace; and he requested to descend. I agreed; and then issued traffic. I turned Aircraft X to H110 to descend him and avoid the Aircraft Z; then realized that Aircraft Y had finished his line and started descending--taking a turn I did not anticipate. Aircraft X initiated a TCAS RA for Aircraft Y; who was about 1.5 miles S of him. Aircraft Y had Aircraft X in sight; but I do not remember if it was before/after the TCAS RA.I was likely fatigued because I was trying to get training for a trainee and took very few breaks to make this happen. I tried to ensure breaks for the other CPC and trainee; at my own expense. In hindsight; this may not have been the best plan with regards to myself. I could have also prevented this if I had required D01 to bring Aircraft X in on the LOA--which would have brought him in on the E side of the airspace; long after Aircraft Y and Aircraft Z.

Data retrieved from NASA's ASRS site 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.