ATC cleared the wrong aircraft to descend from 12000 to 10000 and may have caused less than standard...

Attributes
ACN	84797
Time
Date	198803
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : atl
State Reference	GA
Altitude	msl bound lower : 10600 msl bound upper : 11000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : atl tower : tys
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 210 flight time total : 10000 flight time type : 5000
ASRS Report	84797
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 2000
ASRS Report	84901
Events
Anomaly	altitude deviation : overshoot
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	Other
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Deviation

Narrative:

Atlanta approach controller was saturated. Radio calls were constant. We were especially careful as our flight company NOTAMS showed xyz arriving at the same time as us, bxyz. Several radio calls were missed by other aircraft and approach control as they stepped on each other. The controller sounded harried. He issued a descent from 12000' to 10000' to us at the usual time. We responded and descended to 10600' where he called for our immed climb to 11000'. We responded, climbing to 11000', and added that we had been cleared down. He acknowledged, 'I screwed up'. We saw the conflicting traffic; it was not a collision threat. Our conclusions: considering the workload, I would have been surprised if there had not been an error. Contributing to the problem was the similarity in call sign within one company's operation. Supplemental information in acn 84901: in my opinion, the controller was handling too many aircraft at once.

Original NASA ASRS Text

Title: ATC CLEARED THE WRONG ACFT TO DESCEND FROM 12000 TO 10000 AND MAY HAVE CAUSED LESS THAN STANDARD SEPARATION.

Narrative: ATLANTA APCH CTLR WAS SATURATED. RADIO CALLS WERE CONSTANT. WE WERE ESPECIALLY CAREFUL AS OUR FLT COMPANY NOTAMS SHOWED XYZ ARRIVING AT THE SAME TIME AS US, BXYZ. SEVERAL RADIO CALLS WERE MISSED BY OTHER ACFT AND APCH CTL AS THEY STEPPED ON EACH OTHER. THE CTLR SOUNDED HARRIED. HE ISSUED A DESCENT FROM 12000' TO 10000' TO US AT THE USUAL TIME. WE RESPONDED AND DESCENDED TO 10600' WHERE HE CALLED FOR OUR IMMED CLIMB TO 11000'. WE RESPONDED, CLIMBING TO 11000', AND ADDED THAT WE HAD BEEN CLRED DOWN. HE ACKNOWLEDGED, 'I SCREWED UP'. WE SAW THE CONFLICTING TFC; IT WAS NOT A COLLISION THREAT. OUR CONCLUSIONS: CONSIDERING THE WORKLOAD, I WOULD HAVE BEEN SURPRISED IF THERE HAD NOT BEEN AN ERROR. CONTRIBUTING TO THE PROBLEM WAS THE SIMILARITY IN CALL SIGN WITHIN ONE COMPANY'S OPERATION. SUPPLEMENTAL INFORMATION IN ACN 84901: IN MY OPINION, THE CTLR WAS HANDLING TOO MANY ACFT AT ONCE.

Data retrieved from NASA's ASRS site as of August 2007 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.

ATC cleared the wrong aircraft to descend from 12000 to 10000 and may have caused less than standard separation.