Flight crew of an air carrier large transport aircraft deviated from assigned altitude in response t...

Attributes
ACN	241935
Time
Date	199305
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : mzb airport : san
State Reference	CA
Altitude	msl bound lower : 11000 msl bound upper : 11400
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : san
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	climbout : intermediate altitude
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 230 flight time total : 15000 flight time type : 3700
ASRS Report	241935
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : took evasive action flight crew : returned to intended course or assigned course
Consequence	Other
Miss Distance	horizontal : 6000 vertical : 400
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

TCASII indicated an aircraft approaching from our 11 O'clock at 5 mi, 400 ft below our altitude, and in a climb. TCASII instructed us to climb and about the same time the controller issued us a 10 degree right turn for traffic. We acknowledged the turn and advised that we were starting a climb from 11000 ft (cruise altitude) to comply with TCASII. At approximately 11250 ft, I observed the other aircraft passing on our left at approximately 1 mi and 400 ft below our altitude (400 ft observed on TCASII). We informed the controller that we had the other aircraft in sight and were returning to our assigned altitude of 11000 ft.

Original NASA ASRS Text

Title: FLC OF AN ACR LGT ACFT DEVIATED FROM ASSIGNED ALT IN RESPONSE TO A TCASII RA.

Narrative: TCASII INDICATED AN ACFT APCHING FROM OUR 11 O'CLOCK AT 5 MI, 400 FT BELOW OUR ALT, AND IN A CLB. TCASII INSTRUCTED US TO CLB AND ABOUT THE SAME TIME THE CTLR ISSUED US A 10 DEG R TURN FOR TFC. WE ACKNOWLEDGED THE TURN AND ADVISED THAT WE WERE STARTING A CLB FROM 11000 FT (CRUISE ALT) TO COMPLY WITH TCASII. AT APPROX 11250 FT, I OBSERVED THE OTHER ACFT PASSING ON OUR L AT APPROX 1 MI AND 400 FT BELOW OUR ALT (400 FT OBSERVED ON TCASII). WE INFORMED THE CTLR THAT WE HAD THE OTHER ACFT IN SIGHT AND WERE RETURNING TO OUR ASSIGNED ALT OF 11000 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.

Flight crew of an air carrier large transport aircraft deviated from assigned altitude in response to a TCASII RA.