P50 TRACON controller reported that during a high volume of traffic they did not notice an airborne ...

Attributes
ACN	1522099
Time
Date	201802
Local Time Of Day	0601-1200
Place
Locale Reference	P50.TRACON
State Reference	AZ
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	Bombardier/Canadair Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Route In Use	Visual Approach
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Route In Use	None
Person 1
Function	Approach
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Time Certified In Pos 1 (yrs) 8
Events
Anomaly	ATC Issue All Types Airspace Violation All Types Conflict Airborne Conflict Deviation - Procedural FAR Deviation - Procedural Published Material / Policy

Narrative:

During a period of high traffic volume due to a runway closure I was working the finals sector for phx. Aircraft X was approximately 18 miles east of the airport at 5;400 ft when turned to a 290 heading and cleared for a visual approach 25L. I continued to work numerous other aircraft on frequency and failed to notice that aircraft X had descended and left the class bravo airspace and into an ffz's class delta airspace. Upon reviewing the radar replay aircraft X had descended to 3;100 ft and appeared to directly overfly aircraft Y in ffz's traffic pattern at 3;000 ft. There was a conflict alert on the replay but due to traffic volume I never saw or heard the conflict alert. Aircraft X appeared to climb back to 3;200 ft and then descended again and finished the approach. The pilot never reported a TCAS ever or TCAS RA. In my opinion during the entire 6 week closure of the north runway the traffic volume was too high. I would recommend a comprehensive review of the procedures and traffic rate that were agreed upon between TRACON and center.

Original NASA ASRS Text

Title: P50 TRACON Controller reported that during a high volume of traffic they did not notice an airborne conflict after an aircraft descend out of Class B airspace and into Class D airspace.

Narrative: During a period of high traffic volume due to a runway closure I was working the finals sector for PHX. Aircraft X was approximately 18 miles east of the airport at 5;400 ft when turned to a 290 heading and cleared for a Visual Approach 25L. I continued to work numerous other aircraft on frequency and failed to notice that Aircraft X had descended and left the class Bravo airspace and into an FFZ's Class Delta airspace. Upon reviewing the radar replay Aircraft X had descended to 3;100 ft and appeared to directly overfly Aircraft Y in FFZ's traffic pattern at 3;000 ft. There was a conflict alert on the replay but due to traffic volume I never saw or heard the conflict alert. Aircraft X appeared to climb back to 3;200 ft and then descended again and finished the approach. The pilot never reported a TCAS ever or TCAS RA. In my opinion during the entire 6 week closure of the north runway the traffic volume was too high. I would recommend a comprehensive review of the procedures and traffic rate that were agreed upon between TRACON and Center.

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.

P50 TRACON controller reported that during a high volume of traffic they did not notice an airborne conflict after an aircraft descend out of class B airspace and into class D airspace.