Air carrier receives TCASII RA. Responds with descent.

Attributes
ACN	198487
Time
Date	199201
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : sjn
State Reference	AZ
Altitude	msl bound lower : 26700 msl bound upper : 27000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zab
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	cruise other
Flight Plan	IFR
Aircraft 2
Operator	other
Make Model Name	Military Trainer
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : commercial pilot : atp pilot : instrument
Experience	flight time last 90 days : 220 flight time total : 7100 flight time type : 3500
ASRS Report	198487
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : flight engineer pilot : instrument
Experience	flight time last 90 days : 50 flight time total : 7000 flight time type : 650
ASRS Report	198662
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Northeast on J18 at FL270. TCASII issued a TA followed by traffic RA. Captain complied with descent using vertical speed mode of DFGS. RA stopped descent command after 200 ft of descent with aircraft at FL268. Captain immediately returned aircraft back to 270 assigned. ZAB controller questioned flight's altitude at start of descent. We informed him we were descending out of FL270 on a TCASII RA. He then informed flight that traffic was an MTR, at 12 O'clock at FL280. This agrees with initial TA. Air carrier flight intrail of ours also informed center controller of a TCASII alert and requested TA. ZAB controller stated that the RA did not appear to be valid, based on the 1000 ft of vertical separation. Crew concurs with ZAB controller.

Original NASA ASRS Text

Title: ACR RECEIVES TCASII RA. RESPONDS WITH DSCNT.

Narrative: NE ON J18 AT FL270. TCASII ISSUED A TA FOLLOWED BY TFC RA. CAPT COMPLIED WITH DSCNT USING VERT SPD MODE OF DFGS. RA STOPPED DSCNT COMMAND AFTER 200 FT OF DSCNT WITH ACFT AT FL268. CAPT IMMEDIATELY RETURNED ACFT BACK TO 270 ASSIGNED. ZAB CTLR QUESTIONED FLT'S ALT AT START OF DSCNT. WE INFORMED HIM WE WERE DSNDING OUT OF FL270 ON A TCASII RA. HE THEN INFORMED FLT THAT TFC WAS AN MTR, AT 12 O'CLOCK AT FL280. THIS AGREES WITH INITIAL TA. ACR FLT INTRAIL OF OURS ALSO INFORMED CENTER CTLR OF A TCASII ALERT AND REQUESTED TA. ZAB CTLR STATED THAT THE RA DID NOT APPEAR TO BE VALID, BASED ON THE 1000 FT OF VERT SEPARATION. CREW CONCURS WITH ZAB CTLR.

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.