TCASII RA account closure rate of climbing aircraft, commands descent.

Attributes
ACN	268012
Time
Date	199403
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : ord
State Reference	IL
Altitude	msl bound lower : 6400 msl bound upper : 7500
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : ord
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	descent other
Route In Use	arrival star : star
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : flight engineer pilot : commercial pilot : cfi pilot : atp
Experience	flight time last 90 days : 200 flight time total : 11000 flight time type : 7500
ASRS Report	268012
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	altitude deviation : overshoot inflight encounter other non adherence : clearance
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action other
Consequence	Other
Miss Distance	horizontal : 7000 vertical : 800
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

At approximately 7500 ft a 'traffic' TA was issued by our TCASII. At approximately 7100 ft a 'monitor vertical speed' RA was issued along with a 1500 ft rate of descent lights illuminated. At approximately 7100-7000 ft a 'descend, descend' RA was issued along with 1500 ft rate of descent lights. At approximately 6700 ft an 'increase rate of descent' RA was issued with 2500 ft rate of descent lights. At approximately 6500 ft a 'clear of conflict' was issued and we leveled at approximately 6400 ft'. (Our cleared altitude was 7000 ft.) 1) no TA was issued by approach control prior to the TCASII TA. (Approach was too busy after we got the RA.) 2) the outbound airliner was climbing to 6000. 3) the TCASII software commanded both of us to do the opposite response had we been in VMC. 4) the outbound traffic (at 90 degree to our course) subsequently followed his TCASII and climbed to approximately 6500 ft.

Original NASA ASRS Text

Title: TCASII RA ACCOUNT CLOSURE RATE OF CLBING ACFT, COMMANDS DSCNT.

Narrative: AT APPROX 7500 FT A 'TFC' TA WAS ISSUED BY OUR TCASII. AT APPROX 7100 FT A 'MONITOR VERT SPD' RA WAS ISSUED ALONG WITH A 1500 FT RATE OF DSCNT LIGHTS ILLUMINATED. AT APPROX 7100-7000 FT A 'DSND, DSND' RA WAS ISSUED ALONG WITH 1500 FT RATE OF DSCNT LIGHTS. AT APPROX 6700 FT AN 'INCREASE RATE OF DSCNT' RA WAS ISSUED WITH 2500 FT RATE OF DSCNT LIGHTS. AT APPROX 6500 FT A 'CLR OF CONFLICT' WAS ISSUED AND WE LEVELED AT APPROX 6400 FT'. (OUR CLRED ALT WAS 7000 FT.) 1) NO TA WAS ISSUED BY APCH CTL PRIOR TO THE TCASII TA. (APCH WAS TOO BUSY AFTER WE GOT THE RA.) 2) THE OUTBOUND AIRLINER WAS CLBING TO 6000. 3) THE TCASII SOFTWARE COMMANDED BOTH OF US TO DO THE OPPOSITE RESPONSE HAD WE BEEN IN VMC. 4) THE OUTBOUND TFC (AT 90 DEG TO OUR COURSE) SUBSEQUENTLY FOLLOWED HIS TCASII AND CLBED TO APPROX 6500 FT.

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.