A B727 received a TCASII RA from an aircraft that was reported to have been level at assigned altitu...

Attributes
ACN	435318
Time
Date	199904
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : mrb.vortac
State Reference	WV
Altitude	msl single value : 28000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc.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 : level
Route In Use	enroute airway : j6.airway
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zdc.artcc
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise : level
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 140 flight time total : 5010 flight time type : 980
ASRS Report	345318
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	other flight crewa other flight crewb
Resolutory Action	none taken : detected after the fact
Supplementary
Problem Areas	Aircraft
Primary Problem	Ambiguous

Narrative:

Cruising along at FL280 we received a TCASII TA 'traffic' alert and saw the target on the display below us and climbing. I assumed the traffic would be leveling below us, but then we got an audible climb command and an RA pitch command on the vsi. I disengaged the autoplt and initiated a climb. The captain informed ATC. We reached FL290, the alerts stopped, and we were cleared back to FL280. The controller said the other traffic had been level for 10 mi before our TCASII warning. I don't know if this was a 'false alarm' or not.

Original NASA ASRS Text

Title: A B727 RECEIVED A TCASII RA FROM AN ACFT THAT WAS RPTED TO HAVE BEEN LEVEL AT ASSIGNED ALT FOR 10 MI.

Narrative: CRUISING ALONG AT FL280 WE RECEIVED A TCASII TA 'TFC' ALERT AND SAW THE TARGET ON THE DISPLAY BELOW US AND CLBING. I ASSUMED THE TFC WOULD BE LEVELING BELOW US, BUT THEN WE GOT AN AUDIBLE CLB COMMAND AND AN RA PITCH COMMAND ON THE VSI. I DISENGAGED THE AUTOPLT AND INITIATED A CLB. THE CAPT INFORMED ATC. WE REACHED FL290, THE ALERTS STOPPED, AND WE WERE CLRED BACK TO FL280. THE CTLR SAID THE OTHER TFC HAD BEEN LEVEL FOR 10 MI BEFORE OUR TCASII WARNING. I DON'T KNOW IF THIS WAS A 'FALSE ALARM' OR NOT.

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.

A B727 received a TCASII RA from an aircraft that was reported to have been level at assigned altitude for 10 mi.