Sct TRACON front line manager and both pilots reported of a communication problem that led to an alt...

Attributes
ACN	1379460
Time
Date	201608
Local Time Of Day	0001-0600
Place
Locale Reference	LAX.Airport
State Reference	CA
Environment
Light	Night
Aircraft 1
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Descent
Flight Plan	IFR
Person 1
Function	Supervisor / CIC
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Time Certified In Pos 1 (yrs) 5.5
Person 2
Function	Pilot Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 125 Flight Crew Type 813
Events
Anomaly	ATC Issue All Types Deviation - Altitude Excursion From Assigned Altitude Deviation - Procedural Clearance

Narrative:

Controller missed an incorrect read-back. ZLA sector 13 handed off aircraft crossing zumr boundary at higher altitude. Pilots on SADDE6 arrival routinely are given short cuts by ZLA and are asked to cross simon at 12000 feet with the expectation that the pilot will tell them whether they are able to accept the crossing altitude or not. This is not unusual. There are times when pilots do not get a stable descent and many times arrival controllers are giving a completely different crossing altitude than the one previously assigned by the center controller just minutes before.in this case however; I feel that the pilot was unfamiliar. He did not question a 070 altitude that the zumr controller typically will not issue until sadde. The zumr controller missed the read-back and also did not notice the pilot leaving 10000 feet. That was a huge error on the part of the controller because there is an enormous amount of time lapse between 10000 feet and 9000 feet. The controller at any point between these two altitudes could have turned the plane or asked for an immediate climb. I was actively monitoring the final positions during the event. The traffic demand was very slow on zumr. Pilots on the sadde 6 should question any altitude that is not 10000 feet.

Original NASA ASRS Text

Title: SCT TRACON Front Line Manager and both pilots reported of a communication problem that led to an altitude deviation. Controller descended an aircraft to 7;000 and this crew thought it was for them and responded. Controller did not catch the error.

Narrative: Controller missed an incorrect read-back. ZLA Sector 13 handed off aircraft crossing ZUMR boundary at higher altitude. Pilots on SADDE6 arrival routinely are given short cuts by ZLA and are asked to cross SIMON at 12000 feet with the expectation that the pilot will tell them whether they are able to accept the crossing altitude or not. This is not unusual. There are times when pilots do not get a stable descent and many times Arrival Controllers are giving a completely different crossing altitude than the one previously assigned by the Center controller just minutes before.In this case however; I feel that the pilot was unfamiliar. He did not question a 070 altitude that the ZUMR controller typically will not issue until SADDE. The ZUMR controller missed the read-back and also did not notice the pilot leaving 10000 feet. That was a huge error on the part of the controller because there is an enormous amount of time lapse between 10000 feet and 9000 feet. The controller at any point between these two altitudes could have turned the plane or asked for an immediate climb. I was actively monitoring the final positions during the event. The traffic demand was very slow on ZUMR. Pilots on the SADDE 6 should question any altitude that is not 10000 feet.

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.

Sct TRACON front line manager and both pilots reported of a communication problem that led to an altitude deviation. Controller descended an aircraft to 7;000 and this crew thought it was for them and responded. Controller did not catch the error.