Medium large transport on downwind has TCASII RA.

Attributes
ACN	260701
Time
Date	199401
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : mco
State Reference	FL
Altitude	msl bound lower : 3000 msl bound upper : 3500
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : mco
Operator	common carrier : air carrier
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 121
Flight Phase	descent other
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	other : unknown
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : flight engineer pilot : cfi pilot : commercial
Experience	flight time last 90 days : 50 flight time total : 3500 flight time type : 50
ASRS Report	260701
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

On downwind for visual approach runway 18R mco at 3000 ft, we received a TCASII RA for a 'climb.' we were in visual conditions and were talking to approach control. We deviated 500 ft up to level at 3500 ft. At that altitude we received 'monitor vertical speed' with indications not to descend. After 'clear of conflict' we received another 'monitor vertical descent,' then another 'clear of conflict.' we never made visual contact with other aircraft and approach control said they never saw, or were in contact with any aircraft in that area. When the initial 'climb' RA occurred there was some hesitation to follow commands because we were talking to approach and in visual conditions. After discussing the situation on the ground after the flight, the captain and I decided to include TCASII in our takeoff briefs to prevent slow reactions in the future. We never saw the conflicting aircraft and approach knew nothing about any aircraft in that area which leaves some doubt in my mind if it was a real conflict.

Original NASA ASRS Text

Title: MLG ON DOWNWIND HAS TCASII RA.

Narrative: ON DOWNWIND FOR VISUAL APCH RWY 18R MCO AT 3000 FT, WE RECEIVED A TCASII RA FOR A 'CLB.' WE WERE IN VISUAL CONDITIONS AND WERE TALKING TO APCH CTL. WE DEVIATED 500 FT UP TO LEVEL AT 3500 FT. AT THAT ALT WE RECEIVED 'MONITOR VERT SPD' WITH INDICATIONS NOT TO DSND. AFTER 'CLR OF CONFLICT' WE RECEIVED ANOTHER 'MONITOR VERT DSCNT,' THEN ANOTHER 'CLR OF CONFLICT.' WE NEVER MADE VISUAL CONTACT WITH OTHER ACFT AND APCH CTL SAID THEY NEVER SAW, OR WERE IN CONTACT WITH ANY ACFT IN THAT AREA. WHEN THE INITIAL 'CLB' RA OCCURRED THERE WAS SOME HESITATION TO FOLLOW COMMANDS BECAUSE WE WERE TALKING TO APCH AND IN VISUAL CONDITIONS. AFTER DISCUSSING THE SIT ON THE GND AFTER THE FLT, THE CAPT AND I DECIDED TO INCLUDE TCASII IN OUR TKOF BRIEFS TO PREVENT SLOW REACTIONS IN THE FUTURE. WE NEVER SAW THE CONFLICTING ACFT AND APCH KNEW NOTHING ABOUT ANY ACFT IN THAT AREA WHICH LEAVES SOME DOUBT IN MY MIND IF IT WAS A REAL CONFLICT.

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.