Air carrier Y TCASII RA with air carrier X level at assigned altitude.

Attributes
ACN	255208
Time
Date	199310
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : fjc
State Reference	NY
Altitude	msl bound lower : 22000 msl bound upper : 23000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zny
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute : direct enroute airway : zny
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller non radar : 3 controller radar : 1
ASRS Report	255208
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude altitude deviation : undershoot conflict : airborne less severe
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : took evasive action flight crew : returned to intended course or assigned course
Consequence	Other
Miss Distance	horizontal : 6000 vertical : 1500
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

Air carrier X northbound at FL220. Air carrier Y was eastbound in a descent to FL230. I issued each aircraft the traffic. When air carrier Y was at approximately FL236 it got a TCASII RA to climb. Air carrier X got a TCASII RA to descend. Each aircraft did as the RA suggested. After the aircraft cleared they each returned to their assigned altitudes. Possible solution: if TCASII had known air carrier Y was only descending to FL230, this would have been avoided. There were no other aircraft in the vicinity so there was no loss of safety.

Original NASA ASRS Text

Title: ACR Y TCASII RA WITH ACR X LEVEL AT ASSIGNED ALT.

Narrative: ACR X NBOUND AT FL220. ACR Y WAS EBOUND IN A DSCNT TO FL230. I ISSUED EACH ACFT THE TFC. WHEN ACR Y WAS AT APPROX FL236 IT GOT A TCASII RA TO CLB. ACR X GOT A TCASII RA TO DSND. EACH ACFT DID AS THE RA SUGGESTED. AFTER THE ACFT CLRED THEY EACH RETURNED TO THEIR ASSIGNED ALTS. POSSIBLE SOLUTION: IF TCASII HAD KNOWN ACR Y WAS ONLY DSNDING TO FL230, THIS WOULD HAVE BEEN AVOIDED. THERE WERE NO OTHER ACFT IN THE VICINITY SO THERE WAS NO LOSS OF SAFETY.

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.