TCASII RA induces flight crew to execute an altitude deviation during their evasive action climb.

Attributes
ACN	205176
Time
Date	199203
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : yyz
State Reference	ON
Altitude	msl bound lower : 7000 msl bound upper : 7800
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : yyz
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other
Route In Use	departure other departure sid : sid enroute : on vectors enroute airway : ont
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	climbout : intermediate altitude cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : commercial pilot : flight engineer pilot : instrument pilot : atp
Experience	flight time last 90 days : 150 flight time total : 25000 flight time type : 16000
ASRS Report	205176
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : commercial pilot : cfi pilot : atp pilot : instrument
Experience	flight time last 90 days : 110 flight time total : 6000 flight time type : 650
ASRS Report	204655
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe 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
Miss Distance	horizontal : 12000 vertical : 1200
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation

Narrative:

Departed toronto, leveled at 7000 ft as cleared, TCASII gave 12 O'clock, opposite direction traffic that was climbing approximately 1400 ft below our altitude. TCASII then gave a TA on this target, followed by an RA (aural command to climb, with a min climb rate indicated of 1500 FPM). Climbed to 7800 ft. TCASII then issued 'clear of conflict' advisory. Advised ATC of altitude change and returned to assigned altitude. Supplemental information from acn 204655: we advised toronto departure of our climb and our situation. They did not understand why we climbed, indicating that the traffic was clear underneath us and that we should leave our new altitude immediately and descend back to 7000 ft, which we did. I did not feel that TCASII should have given us a climb command. I do feel that the crew handled the situation as trained by following the climb command.

Original NASA ASRS Text

Title: TCASII RA INDUCES FLC TO EXECUTE AN ALTDEV DURING THEIR EVASIVE ACTION CLB.

Narrative: DEPARTED TORONTO, LEVELED AT 7000 FT AS CLRED, TCASII GAVE 12 O'CLOCK, OPPOSITE DIRECTION TFC THAT WAS CLBING APPROX 1400 FT BELOW OUR ALT. TCASII THEN GAVE A TA ON THIS TARGET, FOLLOWED BY AN RA (AURAL COMMAND TO CLB, WITH A MIN CLB RATE INDICATED OF 1500 FPM). CLBED TO 7800 FT. TCASII THEN ISSUED 'CLR OF CONFLICT' ADVISORY. ADVISED ATC OF ALT CHANGE AND RETURNED TO ASSIGNED ALT. SUPPLEMENTAL INFO FROM ACN 204655: WE ADVISED TORONTO DEP OF OUR CLB AND OUR SITUATION. THEY DID NOT UNDERSTAND WHY WE CLBED, INDICATING THAT THE TFC WAS CLR UNDERNEATH US AND THAT WE SHOULD LEAVE OUR NEW ALT IMMEDIATELY AND DSND BACK TO 7000 FT, WHICH WE DID. I DID NOT FEEL THAT TCASII SHOULD HAVE GIVEN US A CLB COMMAND. I DO FEEL THAT THE CREW HANDLED THE SITUATION AS TRAINED BY FOLLOWING THE CLB COMMAND.

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.