Air carrier climbs above assigned altitude due to TCASII alert.

Attributes
ACN	200882
Time
Date	199202
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : hub airport : iah
State Reference	TX
Altitude	msl bound lower : 6000 msl bound upper : 6700
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : iah tower : ash
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	cruise other
Route In Use	arrival other arrival star : star
Flight Plan	IFR
Aircraft 2
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Retractable Gear
Flight Phase	climbout : intermediate altitude
Flight Plan	None
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
ASRS Report	200882
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 7500
ASRS Report	201376
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 6000 vertical : 500
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Air carrier X advised he was climbing from assigned altitude of 6000 ft to 6700 ft due to TCASII RA on a VFR 5500. Traffic was not seen and air carrier X returned to 6000 ft. Supplemental information from acn 201376: we were level at 6000 ft, approximately 20 NM northwest of hou VOR on the struk 7 STAR to hou when the TCASII displayed a TA showing a target at our 12 O'clock, 5400 ft 600 below us and climbing. Distance inside 1 mi (we were on 10 NM range). Approximately 10 seconds later, the RA triggered, showing a 'climb, climb' command. We climbed to 6600 ft before the 'clear of conflict' came. We advised ATC of the command and returned to 6000 ft. ATC showed no traffic in the area. Coincidentally, we were in the general area of a small airport and suspect that a transponder on the ground might have activated the TCASII.

Original NASA ASRS Text

Title: ACR CLBS ABOVE ASSIGNED ALT DUE TO TCASII ALERT.

Narrative: ACR X ADVISED HE WAS CLBING FROM ASSIGNED ALT OF 6000 FT TO 6700 FT DUE TO TCASII RA ON A VFR 5500. TFC WAS NOT SEEN AND ACR X RETURNED TO 6000 FT. SUPPLEMENTAL INFO FROM ACN 201376: WE WERE LEVEL AT 6000 FT, APPROX 20 NM NW OF HOU VOR ON THE STRUK 7 STAR TO HOU WHEN THE TCASII DISPLAYED A TA SHOWING A TARGET AT OUR 12 O'CLOCK, 5400 FT 600 BELOW US AND CLBING. DISTANCE INSIDE 1 MI (WE WERE ON 10 NM RANGE). APPROX 10 SECONDS LATER, THE RA TRIGGERED, SHOWING A 'CLB, CLB' COMMAND. WE CLBED TO 6600 FT BEFORE THE 'CLR OF CONFLICT' CAME. WE ADVISED ATC OF THE COMMAND AND RETURNED TO 6000 FT. ATC SHOWED NO TFC IN THE AREA. COINCIDENTALLY, WE WERE IN THE GENERAL AREA OF A SMALL ARPT AND SUSPECT THAT A TRANSPONDER ON THE GND MIGHT HAVE ACTIVATED THE TCASII.

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.