B757 in holding at FL270 with ZTL experienced TCASII RA when issued descent clearance.

Attributes
ACN	666731
Time
Date	200508
Place
Locale Reference	intersection : macey
State Reference	GA
Altitude	msl single value : 27000
Environment
Weather Elements	Thunderstorm
Light	Night
Aircraft 1
Controlling Facilities	artcc : ztl.artcc
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	descent : holding
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : ztl.artcc
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	descent : holding
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 160 flight time total : 9000 flight time type : 4500
ASRS Report	666731
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	conflict : airborne critical
Independent Detector	aircraft equipment : tcas other flight crewa
Resolutory Action	controller : issued new clearance flight crew : took evasive action
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance

Narrative:

B757-200 holding at macey (FL270) for approximately 35 mins after extensive WX delays; nonstandard holding due to thunderstorms with delays also caused by closed arrival runway. ZTL; controling pattern; questioned about length of delay for fuel planning and possible diversion. Controller unsure about subsequent delays and clears B757-200 to descend and maintain FL240. During descent; a TCASII TA is received that quickly changes to an RA. First officer responds to TCASII instructions and executes a climb back to FL270. Controller apologizes for his error in issuing an erroneous descent clearance. It appeared he was overloaded with severe WX; a closed runway in atl and aircraft backing up at the holding fix.

Original NASA ASRS Text

Title: B757 IN HOLDING AT FL270 WITH ZTL EXPERIENCED TCASII RA WHEN ISSUED DSCNT CLRNC.

Narrative: B757-200 HOLDING AT MACEY (FL270) FOR APPROX 35 MINS AFTER EXTENSIVE WX DELAYS; NONSTANDARD HOLDING DUE TO TSTMS WITH DELAYS ALSO CAUSED BY CLOSED ARR RWY. ZTL; CTLING PATTERN; QUESTIONED ABOUT LENGTH OF DELAY FOR FUEL PLANNING AND POSSIBLE DIVERSION. CTLR UNSURE ABOUT SUBSEQUENT DELAYS AND CLRS B757-200 TO DSND AND MAINTAIN FL240. DURING DSCNT; A TCASII TA IS RECEIVED THAT QUICKLY CHANGES TO AN RA. FO RESPONDS TO TCASII INSTRUCTIONS AND EXECUTES A CLB BACK TO FL270. CTLR APOLOGIZES FOR HIS ERROR IN ISSUING AN ERRONEOUS DSCNT CLRNC. IT APPEARED HE WAS OVERLOADED WITH SEVERE WX; A CLOSED RWY IN ATL AND ACFT BACKING UP AT THE HOLDING FIX.

Data retrieved from NASA's ASRS site as of January 2009 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.