TRACON controller providing OJT on combined positions described a loss of separation event involving...

Narrative:

I was providing OJT on departure east to my trainee during the morning departures. During this period of the day almost all traffic is departures with only an occasional arrival or over flight. All positions were combined which is normal for this time period. A baron checked on frequency at 5;000 ft about 40 miles south southwest of ZZZ. My trainee initially gave the baron a 025 heading and I talked him into letting him stay on course and told him to stop departures at 4;000; so he did. My trainee had several departures off ZZZ including 3 or 4 other departures he was concentrating on sequencing and missing an over flight point out from center; he never told tower to stop jets at 4;000. A phenom 300 departed a nearby airport on 230 heading climbing to 5;000. My trainee attempted to stop the phenom at 4;000 but was too late. The phenom got to about 4;500 before descending to 4;000. My trainee does not have much experience working combined positions; but is nearing check out on departure. Because of this I should have let him vector the baron out of the way like he wanted to. Recommendation; do not put off coordination; take care of point outs and coordination as soon as you realize you are going to need them.

Original NASA ASRS Text

Title: TRACON Controller providing OJT on combined positions described a loss of separation event involving an IFR departure and an overflight; the developmental failing to altitude restrict the departure.

Narrative: I was providing OJT on Departure East to my trainee during the morning departures. During this period of the day almost all traffic is departures with only an occasional arrival or over flight. All positions were combined which is normal for this time period. A Baron checked on frequency at 5;000 FT about 40 miles south southwest of ZZZ. My trainee initially gave the Baron a 025 heading and I talked him into letting him stay on course and told him to stop departures at 4;000; so he did. My trainee had several departures off ZZZ including 3 or 4 other departures he was concentrating on sequencing and missing an over flight point out from Center; he never told Tower to stop jets at 4;000. A Phenom 300 departed a nearby airport on 230 heading climbing to 5;000. My trainee attempted to stop the Phenom at 4;000 but was too late. The Phenom got to about 4;500 before descending to 4;000. My trainee does not have much experience working combined positions; but is nearing check out on departure. Because of this I should have let him vector the Baron out of the way like he wanted to. Recommendation; do not put off coordination; take care of point outs and coordination as soon as you realize you are going to need them.

Data retrieved from NASA's ASRS site as of April 2012 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	975780
Time
Date	201110
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	Baron 55/Cochise
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Flight Plan	IFR
Aircraft 2
Make Model Name	Embraer Phenom 300
Flight Phase	Climb
Route In Use	Vectors
Flight Plan	IFR
Person 1
Function	Approach Departure Instructor
Qualification	Air Traffic Control Fully Certified
Person 2
Function	Trainee Departure Approach
Qualification	Air Traffic Control Developmental
Events
Anomaly	ATC Issue All Types Conflict Airborne Conflict

TRACON controller providing OJT on combined positions described a loss of separation event involving an IFR departure and an overflight; the developmental failing to altitude restrict the departure.