A B-757 flight crew receives a TCASII TA RA on a helicopter that tower thought would be no factor.

Attributes
ACN	586779
Time
Date	200306
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : fll.airport
State Reference	FL
Altitude	agl single value : 1300
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : fll.tower
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer & glide slope : 9l other
Flight Phase	descent : approach descent : intermediate altitude
Flight Plan	IFR
Aircraft 2
Make Model Name	Helicopter
Flight Phase	cruise : level
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 12500 flight time type : 2750
ASRS Report	586779
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	conflict : airborne critical non adherence : required legal separation
Independent Detector	aircraft equipment : tcas
Resolutory Action	flight crew : took precautionary avoidance action
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 500 vertical : 500
Supplementary
Problem Areas	Flight Crew Human Performance Airspace Structure ATC Human Performance
Primary Problem	Ambiguous

Narrative:

Approaching 1300 ft AGL, lined up for runway 9L, landing checklist complete and cleared to land, on localizer and GS, saw TCASII vsi display turn yellow and traffic shown ahead and below -700 ft. The maintenance, display was in large scale and I turned it to the lowest scale to get a better idea where the traffic was relative to us. Shortly thereafter the alert turned to red and TCASII announced 'monitor vertical speed' once. Rate of descent at the time was about 700-800 ft with a slightly rough ride from afternoon thermals. Green arc on the vsi was in the 0-300 FPM range. I flew into the green arc for about 5 seconds at which time the display returned to normal. Meanwhile the PNF notified the tower, which responded they knew of helicopter traffic, but thought it would not be a factor. Almost simultaneously the PNF referenced TCASII then visually spotted the traffic. He announced, 'a helicopter, no factor.' TCASII returned to normal and a correction was made to return to the GS. A normal landing was made within the company published limitations for a stabilized approach and within the defined landing area.

Original NASA ASRS Text

Title: A B-757 FLT CREW RECEIVES A TCASII TA RA ON A HELI THAT TWR THOUGHT WOULD BE NO FACTOR.

Narrative: APCHING 1300 FT AGL, LINED UP FOR RWY 9L, LNDG CHKLIST COMPLETE AND CLRED TO LAND, ON LOC AND GS, SAW TCASII VSI DISPLAY TURN YELLOW AND TFC SHOWN AHEAD AND BELOW -700 FT. THE MAINT, DISPLAY WAS IN LARGE SCALE AND I TURNED IT TO THE LOWEST SCALE TO GET A BETTER IDEA WHERE THE TFC WAS RELATIVE TO US. SHORTLY THEREAFTER THE ALERT TURNED TO RED AND TCASII ANNOUNCED 'MONITOR VERT SPD' ONCE. RATE OF DSCNT AT THE TIME WAS ABOUT 700-800 FT WITH A SLIGHTLY ROUGH RIDE FROM AFTERNOON THERMALS. GREEN ARC ON THE VSI WAS IN THE 0-300 FPM RANGE. I FLEW INTO THE GREEN ARC FOR ABOUT 5 SECONDS AT WHICH TIME THE DISPLAY RETURNED TO NORMAL. MEANWHILE THE PNF NOTIFIED THE TWR, WHICH RESPONDED THEY KNEW OF HELI TFC, BUT THOUGHT IT WOULD NOT BE A FACTOR. ALMOST SIMULTANEOUSLY THE PNF REFED TCASII THEN VISUALLY SPOTTED THE TFC. HE ANNOUNCED, 'A HELI, NO FACTOR.' TCASII RETURNED TO NORMAL AND A CORRECTION WAS MADE TO RETURN TO THE GS. A NORMAL LNDG WAS MADE WITHIN THE COMPANY PUBLISHED LIMITATIONS FOR A STABILIZED APCH AND WITHIN THE DEFINED LNDG AREA.

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.