ZID associate controller observes conflict between climbing and descending traffic, requiring a TCAS...

Attributes
ACN	451065
Time
Date	199910
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : vhp.vor
State Reference	IN
Altitude	msl bound lower : 26500 msl bound upper : 27000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zid.artcc
Operator	common carrier : air carrier
Make Model Name	Challenger CL604
Operating Under FAR Part	Part 121
Navigation In Use	other other vortac
Flight Phase	cruise : descent cruise : enroute altitude change
Route In Use	enroute other
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zid.artcc
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	cruise : descent cruise : enroute altitude change
Route In Use	enroute other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : handoff position
Qualification	pilot : instrument
Experience	controller military : 3 controller radar : 13 controller time certified in position1 : 1.5 flight time total : 300
ASRS Report	451065
Person 2
Affiliation	government : faa
Function	controller : radar
Experience	controller radar : 7
ASRS Report	451498
Events
Anomaly	conflict : airborne critical non adherence : required legal separation non adherence : published procedure
Independent Detector	atc equipment : conflict alert aircraft equipment : tcas other controllera other controllerb other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew faa : investigated
Miss Distance	horizontal : 0 vertical : 500
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

I had just plugged in and was coordinating pointouts with other sectors. A min or so later, I noticed the #1 aircraft (aircraft X) was at FL265 with a temporary altitude of FL260 typed in. The radar person noticed it at the same time and descended aircraft #1 to FL260. Aircraft #2 (aircraft Y) was descending to FL270 and was about to level when he took a TCASII alert and climbed. It was determined that the radar controller had cleared aircraft #1 to FL270 and the pilot acknowledged FL270, when the radar controller intended to say FL260. It was determined that I was on the landlines coordinating pointouts when the clearance to FL270 to aircraft #1 was issued. I did not hear FL270 being issued to aircraft #1 with a temporary altitude of FL260 being put in the data block. Supplemental information from acn 451303: at FL270 we got an RA to descend. Also ATC told us to descend to FL260. I called ZID and was told there was a problem on the controller's side. He told me we were cleared to FL270 in error!

Original NASA ASRS Text

Title: ZID ASSOCIATE CTLR OBSERVES CONFLICT BTWN CLBING AND DSNDING TFC, REQUIRING A TCASII MANEUVER.

Narrative: I HAD JUST PLUGGED IN AND WAS COORDINATING POINTOUTS WITH OTHER SECTORS. A MIN OR SO LATER, I NOTICED THE #1 ACFT (ACFT X) WAS AT FL265 WITH A TEMPORARY ALT OF FL260 TYPED IN. THE RADAR PERSON NOTICED IT AT THE SAME TIME AND DSNDED ACFT #1 TO FL260. ACFT #2 (ACFT Y) WAS DSNDING TO FL270 AND WAS ABOUT TO LEVEL WHEN HE TOOK A TCASII ALERT AND CLBED. IT WAS DETERMINED THAT THE RADAR CTLR HAD CLRED ACFT #1 TO FL270 AND THE PLT ACKNOWLEDGED FL270, WHEN THE RADAR CTLR INTENDED TO SAY FL260. IT WAS DETERMINED THAT I WAS ON THE LANDLINES COORDINATING POINTOUTS WHEN THE CLRNC TO FL270 TO ACFT #1 WAS ISSUED. I DID NOT HEAR FL270 BEING ISSUED TO ACFT #1 WITH A TEMPORARY ALT OF FL260 BEING PUT IN THE DATA BLOCK. SUPPLEMENTAL INFO FROM ACN 451303: AT FL270 WE GOT AN RA TO DSND. ALSO ATC TOLD US TO DSND TO FL260. I CALLED ZID AND WAS TOLD THERE WAS A PROB ON THE CTLR'S SIDE. HE TOLD ME WE WERE CLRED TO FL270 IN ERROR!

Data retrieved from NASA's ASRS site as of July 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.

ZID associate controller observes conflict between climbing and descending traffic, requiring a TCASII maneuver.