An air carrier medium large transport climbed in response to a TCASII command.

Attributes
ACN	252665
Time
Date	199309
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : aus
State Reference	TX
Altitude	msl bound lower : 5000 msl bound upper : 6000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : aus
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 cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Retractable Gear
Flight Phase	cruise other
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 50 flight time total : 4700 flight time type : 310
ASRS Report	252665
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 65 flight time total : 2350 flight time type : 320
ASRS Report	252662
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : nmac inflight encounter : weather 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 : 0 vertical : 500
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

12 DME from austin VOR at 5000 ft MSL in IMC conditions, we received a TA. We were receiving radar vectors by austin approach control, 'turn to a heading of 120 degrees, small aircraft at 12 O'clock.' we turned to a heading of 120 degrees which would take us into some heavy precipitation. We requested a turn to a heading of 115 degrees to avoid the WX. About the time we expected a readback from approach control, we received our TCASII RA (TCASII indicated that the traffic was 100 ft below our aircraft, and less than 1 NM at 12 O'clock). We immediately took appropriate evasive measures and climbed to 6000 ft, and advised approach control. Had we not believed our TCASII, and climbed as it had directed, we might have had a midair collision.

Original NASA ASRS Text

Title: AN ACR MLG CLBED IN RESPONSE TO A TCASII COMMAND.

Narrative: 12 DME FROM AUSTIN VOR AT 5000 FT MSL IN IMC CONDITIONS, WE RECEIVED A TA. WE WERE RECEIVING RADAR VECTORS BY AUSTIN APCH CTL, 'TURN TO A HDG OF 120 DEGS, SMA AT 12 O'CLOCK.' WE TURNED TO A HDG OF 120 DEGS WHICH WOULD TAKE US INTO SOME HVY PRECIPITATION. WE REQUESTED A TURN TO A HDG OF 115 DEGS TO AVOID THE WX. ABOUT THE TIME WE EXPECTED A READBACK FROM APCH CTL, WE RECEIVED OUR TCASII RA (TCASII INDICATED THAT THE TFC WAS 100 FT BELOW OUR ACFT, AND LESS THAN 1 NM AT 12 O'CLOCK). WE IMMEDIATELY TOOK APPROPRIATE EVASIVE MEASURES AND CLBED TO 6000 FT, AND ADVISED APCH CTL. HAD WE NOT BELIEVED OUR TCASII, AND CLBED AS IT HAD DIRECTED, WE MIGHT HAVE HAD A MIDAIR COLLISION.

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.