Widebody transport at cruise receives TCASII RA. Responds but center says no close traffic.

Attributes
ACN	211429
Time
Date	199205
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : lny
State Reference	HI
Altitude	msl bound lower : 13500 msl bound upper : 14000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute airway : zhn
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 14500 flight time type : 1500
ASRS Report	211429
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 130 flight time total : 10000 flight time type : 4000
ASRS Report	211337
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : clearance non adherence : required legal separation other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 15000 vertical : 500
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While cruising at 14000 ft en route to hnl from ogg on julie 2 arrival TCASII gave a RA with descend command. I looked at TCASII screen to see where it was as there was no TA preceding the RA. I saw 2 red RA's one on top of other. The top one blocking out the data block of bottom one. I disengaged the autoplt and initiated a descent of 500-800 FPM as commanded on vsi. All 3 of us looked to see if we could spot the conflicting aircraft but only saw a widebody transport that was at 13000 ft at 1 O'clock coming across in front of us. At time of descent captain called ATC to inform them we were descending in response to RA command. We leveled out at 13500 as TCASII gave us clear of conflict and climbed back to 14000 ft. Widebody transport was at about 2-3 mi at time we started climb back to 14000 ft. ATC was questioned by us if they saw anyone else around us but said they didn't show anyone else on their radar but widebody transport and us. We assumed it was either a false indication or the traffic had a weak transponder that we picked up but center didn't.

Original NASA ASRS Text

Title: WDB AT CRUISE RECEIVES TCASII RA. RESPONDS BUT CTR SAYS NO CLOSE TFC.

Narrative: WHILE CRUISING AT 14000 FT ENRTE TO HNL FROM OGG ON JULIE 2 ARR TCASII GAVE A RA WITH DSND COMMAND. I LOOKED AT TCASII SCREEN TO SEE WHERE IT WAS AS THERE WAS NO TA PRECEDING THE RA. I SAW 2 RED RA'S ONE ON TOP OF OTHER. THE TOP ONE BLOCKING OUT THE DATA BLOCK OF BOTTOM ONE. I DISENGAGED THE AUTOPLT AND INITIATED A DSCNT OF 500-800 FPM AS COMMANDED ON VSI. ALL 3 OF US LOOKED TO SEE IF WE COULD SPOT THE CONFLICTING ACFT BUT ONLY SAW A WDB THAT WAS AT 13000 FT AT 1 O'CLOCK COMING ACROSS IN FRONT OF US. AT TIME OF DSCNT CAPT CALLED ATC TO INFORM THEM WE WERE DSNDING IN RESPONSE TO RA COMMAND. WE LEVELED OUT AT 13500 AS TCASII GAVE US CLR OF CONFLICT AND CLBED BACK TO 14000 FT. WDB WAS AT ABOUT 2-3 MI AT TIME WE STARTED CLB BACK TO 14000 FT. ATC WAS QUESTIONED BY US IF THEY SAW ANYONE ELSE AROUND US BUT SAID THEY DIDN'T SHOW ANYONE ELSE ON THEIR RADAR BUT WDB AND US. WE ASSUMED IT WAS EITHER A FALSE INDICATION OR THE TFC HAD A WEAK TRANSPONDER THAT WE PICKED UP BUT CTR DIDN'T.

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.