TCASII computer gave intruder warning and RA to climb, flight climbed, made a go around.

Attributes
ACN	191039
Time
Date	199110
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : lax airport : las
State Reference	NV
Altitude	msl bound lower : 6500 msl bound upper : 7500
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : las
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	climbout : intermediate altitude descent : approach descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : commercial pilot : atp
Experience	flight time last 90 days : 240 flight time total : 9000 flight time type : 6500
ASRS Report	191039
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : airborne less severe other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action other
Consequence	Other
Miss Distance	horizontal : 500 vertical : 500
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation

Narrative:

We were turning left base on a visual approach to runway 25L at mccarran airport, lax. Our position was about 6 DME east of las VOR and 2-3 south of the 25L localizer. We were cleared for a visual approach to 25L reference traffic at our 1 O'clock who was on a visual to 25R from the ese of the airport. We would be turning inside of him on our base to final, as he was at our 1 O'clock 1-2 mi during our left base turn. Our altitude was 6500 MSL, landing gear down, flap position 15 and speed 150 KIAS. As we passed through heading about 010 degree inside our traffic who was now approximately 1 mi or less as we continued our base to final turn. We then got a 'monitor vertical speed' from TCASII. We slowed our descent and tried to visually figure our exact position from our traffic as we continued our final turn at about 15 degree bank. TCASII then commanded a 'climb, climb, climb' and showed a 1500 FPM climb to keep up clear of traffic. As we started a climb, TCASII gave us another 'climb, climb, climb' still showing a 1500 FPM climb to avoid traffic. We then initiated a missed approach and climbed to above 7000 MSL when TCASII discontinued the climb command. I called tower and told them we had a TCASII commanded climb, and we were not too high to continue our approach. We were instructed to go back to approach control and were vectored for an uneventful approach and landing. I made the pull up based on TCASII information because in our base turn we were belly up to our traffic which made it very hard visually to confirm that our courses would not converge too closely. Also, I wasn't totally certain TCASII hadn't picked up another target we hadn't seen. Thirdly, I didn't think there was time to call tower to have them confirm our position from traffic. Also, the volume of the TCASII commands is so loud that it greatly detracts from crew coordination during critical phases of flight. Also, I don't believe the TCASII computer can keep up with our projected flight path when the aircraft turn rate is high. Also, there was no traffic above us as we initiated the missed approach.

Original NASA ASRS Text

Title: TCASII COMPUTER GAVE INTRUDER WARNING AND RA TO CLB, FLT CLBED, MADE A GAR.

Narrative: WE WERE TURNING L BASE ON A VISUAL APCH TO RWY 25L AT MCCARRAN ARPT, LAX. OUR POS WAS ABOUT 6 DME E OF LAS VOR AND 2-3 S OF THE 25L LOC. WE WERE CLRED FOR A VISUAL APCH TO 25L REF TFC AT OUR 1 O'CLOCK WHO WAS ON A VISUAL TO 25R FROM THE ESE OF THE ARPT. WE WOULD BE TURNING INSIDE OF HIM ON OUR BASE TO FINAL, AS HE WAS AT OUR 1 O'CLOCK 1-2 MI DURING OUR L BASE TURN. OUR ALT WAS 6500 MSL, LNDG GEAR DOWN, FLAP POS 15 AND SPD 150 KIAS. AS WE PASSED THROUGH HDG ABOUT 010 DEG INSIDE OUR TFC WHO WAS NOW APPROX 1 MI OR LESS AS WE CONTINUED OUR BASE TO FINAL TURN. WE THEN GOT A 'MONITOR VERT SPD' FROM TCASII. WE SLOWED OUR DSCNT AND TRIED TO VISUALLY FIGURE OUR EXACT POS FROM OUR TFC AS WE CONTINUED OUR FINAL TURN AT ABOUT 15 DEG BANK. TCASII THEN COMMANDED A 'CLB, CLB, CLB' AND SHOWED A 1500 FPM CLB TO KEEP UP CLR OF TFC. AS WE STARTED A CLB, TCASII GAVE US ANOTHER 'CLB, CLB, CLB' STILL SHOWING A 1500 FPM CLB TO AVOID TFC. WE THEN INITIATED A MISSED APCH AND CLBED TO ABOVE 7000 MSL WHEN TCASII DISCONTINUED THE CLB COMMAND. I CALLED TWR AND TOLD THEM WE HAD A TCASII COMMANDED CLB, AND WE WERE NOT TOO HIGH TO CONTINUE OUR APCH. WE WERE INSTRUCTED TO GO BACK TO APCH CTL AND WERE VECTORED FOR AN UNEVENTFUL APCH AND LNDG. I MADE THE PULL UP BASED ON TCASII INFO BECAUSE IN OUR BASE TURN WE WERE BELLY UP TO OUR TFC WHICH MADE IT VERY HARD VISUALLY TO CONFIRM THAT OUR COURSES WOULD NOT CONVERGE TOO CLOSELY. ALSO, I WASN'T TOTALLY CERTAIN TCASII HADN'T PICKED UP ANOTHER TARGET WE HADN'T SEEN. THIRDLY, I DIDN'T THINK THERE WAS TIME TO CALL TWR TO HAVE THEM CONFIRM OUR POS FROM TFC. ALSO, THE VOLUME OF THE TCASII COMMANDS IS SO LOUD THAT IT GREATLY DETRACTS FROM CREW COORD DURING CRITICAL PHASES OF FLT. ALSO, I DON'T BELIEVE THE TCASII COMPUTER CAN KEEP UP WITH OUR PROJECTED FLT PATH WHEN THE ACFT TURN RATE IS HIGH. ALSO, THERE WAS NO TFC ABOVE US AS WE INITIATED THE MISSED APCH.

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.