TCAS RA dictated climb to avoid traffic.

Attributes
ACN	183796
Time
Date	199107
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : tmu
State Reference	CT
Altitude	msl bound lower : 9500 msl bound upper : 10800
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	descent : approach
Route In Use	enroute airway : pvd
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : instrument pilot : commercial
Experience	flight time last 90 days : 200 flight time total : 4000 flight time type : 400
ASRS Report	183796
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : commercial pilot : instrument
Events
Anomaly	conflict : airborne less severe
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	vertical : 500
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Our aircraft was equipped with TCAS and while leveling at 10000 ft MSL during a descent we got a resolution advisory on traffic 500 ft below us and to the right. TCAS called for a climb which the captain did. Passing 10800 the TCAS showed clear of traffic and we started a descent back down to our assigned altitude of 10000 ft. I made a call to ATC during this to advise them of our RA and our climb to avoid traffic. At this time I noticed the captain had descended through 10000 ft passing 9600 ft. I alerted him to climb back to 10000 ft.

Original NASA ASRS Text

Title: TCAS RA DICTATED CLB TO AVOID TFC.

Narrative: OUR ACFT WAS EQUIPPED WITH TCAS AND WHILE LEVELING AT 10000 FT MSL DURING A DSCNT WE GOT A RESOLUTION ADVISORY ON TFC 500 FT BELOW US AND TO THE R. TCAS CALLED FOR A CLB WHICH THE CAPT DID. PASSING 10800 THE TCAS SHOWED CLR OF TFC AND WE STARTED A DSCNT BACK DOWN TO OUR ASSIGNED ALT OF 10000 FT. I MADE A CALL TO ATC DURING THIS TO ADVISE THEM OF OUR RA AND OUR CLB TO AVOID TFC. AT THIS TIME I NOTICED THE CAPT HAD DSNDED THROUGH 10000 FT PASSING 9600 FT. I ALERTED HIM TO CLB BACK TO 10000 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.