TRACON controller described ATC airspace deviation event when they failed to hear/correct wrong alti...

Attributes
ACN	859068
Time
Date	200911
Place
Locale Reference	ZZZ.TRACON
State Reference	US
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Flight Plan	IFR
Person 1
Function	Approach
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Military 1 Air Traffic Control Radar 22 Air Traffic Control Time Certified In Pos 1 (mon) 10 Air Traffic Control Time Certified In Pos 1 (yrs) 9
Events
Anomaly	ATC Issue All Types Deviation - Procedural Clearance
Miss Distance	Horizontal 5 Vertical 0

Narrative:

I was working the (arrival) sector approach control. Air carrier X checked on the arrival. I issued to expect a visual approach to runway xxr and issued a descent clearance to 9000 ft. A few minutes later I observed air carrier X descending thru 8600 ft and issued 8000 ft and a turn to heading 180 to keep the aircraft out of the departure corridor. No read back. I re-issued the instructions as the aircraft descended thru 7800 ft. The pilot questioned and still took no action. I re-issued the clearance to air carrier X and advised that I had issued 9000 initially. After reviewing the tape it has been determined that I did issue 9000 ft but missed a read back of 7000 ft by air carrier X. During this event there was never a loss of separation or even the chance of losing separation with any other aircraft. I screwed up and missed a read back; the pilot screwed up and miss understood a control instruction then further jeopardized the situation by questioning; instead of reacting to control instructions to correct the problem. I did take action to coordinate with the effected sector to avoid conflicts and a deviation; however an ATC deviation was recorded.

Original NASA ASRS Text

Title: TRACON Controller described ATC airspace deviation event when they failed to hear/correct wrong altitude assignment read back but did complete required airspace entry coordination.

Narrative: I was working the (arrival) sector Approach Control. Air Carrier X checked on the arrival. I issued to expect a visual approach to Runway XXR and issued a descent clearance to 9000 FT. A few minutes later I observed Air Carrier X descending thru 8600 FT and issued 8000 FT and a turn to heading 180 to keep the aircraft out of the departure corridor. No read back. I re-issued the instructions as the aircraft descended thru 7800 FT. The pilot questioned and still took no action. I re-issued the clearance to Air Carrier X and advised that I had issued 9000 initially. After reviewing the tape it has been determined that I did issue 9000 FT but missed a read back of 7000 FT by Air Carrier X. During this event there was never a loss of separation or even the chance of losing separation with any other aircraft. I screwed up and missed a read back; the pilot screwed up and miss understood a control instruction then further jeopardized the situation by questioning; instead of reacting to control instructions to correct the problem. I did take action to coordinate with the effected sector to avoid conflicts and a deviation; however an ATC deviation was recorded.

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.

TRACON controller described ATC airspace deviation event when they failed to hear/correct wrong altitude assignment read back but did complete required airspace entry coordination.