Altitude deviation.

Attributes
ACN	216617
Time
Date	199207
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : lax
State Reference	CA
Altitude	msl bound lower : 5500 msl bound upper : 6000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : lax
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	cruise other descent : approach
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	descent : approach
Route In Use	approach : straight in enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 90 flight time total : 2700 flight time type : 90
ASRS Report	216617
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : cfi pilot : atp pilot : commercial
Experience	flight time last 90 days : 176 flight time total : 10000 flight time type : 5493
ASRS Report	216615
Events
Anomaly	altitude deviation : excursion from assigned altitude altitude deviation : overshoot conflict : airborne less severe non adherence : required legal separation non adherence : clearance other anomaly other
Independent Detector	other controllera other flight crewa
Resolutory Action	controller : issued new clearance
Consequence	Other
Miss Distance	horizontal : 3000 vertical : 700
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

We were approaching lax from seal beach VOR at 7000 ft. Lax approach was vectoring us across the approach paths for runways 25L and right for our approach to runway 24R. The approach controller cleared an aircraft approaching the runway 25 complex at lax out of 6000 ft for 5000 ft, and immediately cleared us out of 7000 ft for 6000 ft. The controller pointed out the traffic, which we immediately acquired visually. Our TCASII then began giving us a TA for the aircraft approaching runways 25. Distracted by the aural TCASII warning, I failed to note that the autoplt's level-off altitude of 6000 ft had become disarmed. I immediately engaged the altitude hold descending through 5800 ft. The autoplt lost an additional 100 ft, descending to 5700 ft before leveling off. The controller noticed this, and cleared us down to 5500 ft. Because of the aural warning from the TCASII, I only heard 'cleared to 5000 ft' and began a descent to 5000. Supplemental information from acn 216615: we both confirmed the traffic and I told approach we had the traffic in sight. I then turned my head to the left to depress the PA transmitter button and asked the flight attendants to be seated for landing. When I turned back, I noticed the aircraft at 5800 ft and descending. I called out the descent to the first officer who was flying. The aircraft continued to descend so I said stop your descent. The copilot did not react so I took control and stopped descent. Controller then told us to descend and maintain 5500 and shortly after cleared us for the approach to runway 24R. The copilot was confused and did not react because he froze up for a couple of seconds. He is new to far 121 operations, new to the airline industry and new to modern technology. I believe this all contributed to overwhelming him to the point that he just froze up. I'm not sure how we correct this problem, but I can say that the initial approach segment is very busy in a 2-MAN cockpit and it is very difficult to perform your own duties, supervise a new pilot and react quickly enough to prevent problems, all at the same time.

Original NASA ASRS Text

Title: ALTDEV.

Narrative: WE WERE APCHING LAX FROM SEAL BEACH VOR AT 7000 FT. LAX APCH WAS VECTORING US ACROSS THE APCH PATHS FOR RWYS 25L AND R FOR OUR APCH TO RWY 24R. THE APCH CTLR CLRED AN ACFT APCHING THE RWY 25 COMPLEX AT LAX OUT OF 6000 FT FOR 5000 FT, AND IMMEDIATELY CLRED US OUT OF 7000 FT FOR 6000 FT. THE CTLR POINTED OUT THE TFC, WHICH WE IMMEDIATELY ACQUIRED VISUALLY. OUR TCASII THEN BEGAN GIVING US A TA FOR THE ACFT APCHING RWYS 25. DISTRACTED BY THE AURAL TCASII WARNING, I FAILED TO NOTE THAT THE AUTOPLT'S LEVEL-OFF ALT OF 6000 FT HAD BECOME DISARMED. I IMMEDIATELY ENGAGED THE ALT HOLD DSNDING THROUGH 5800 FT. THE AUTOPLT LOST AN ADDITIONAL 100 FT, DSNDING TO 5700 FT BEFORE LEVELING OFF. THE CTLR NOTICED THIS, AND CLRED US DOWN TO 5500 FT. BECAUSE OF THE AURAL WARNING FROM THE TCASII, I ONLY HEARD 'CLRED TO 5000 FT' AND BEGAN A DSCNT TO 5000. SUPPLEMENTAL INFO FROM ACN 216615: WE BOTH CONFIRMED THE TFC AND I TOLD APCH WE HAD THE TFC IN SIGHT. I THEN TURNED MY HEAD TO THE L TO DEPRESS THE PA XMITTER BUTTON AND ASKED THE FLT ATTENDANTS TO BE SEATED FOR LNDG. WHEN I TURNED BACK, I NOTICED THE ACFT AT 5800 FT AND DSNDING. I CALLED OUT THE DSCNT TO THE FO WHO WAS FLYING. THE ACFT CONTINUED TO DSND SO I SAID STOP YOUR DSCNT. THE COPLT DID NOT REACT SO I TOOK CTL AND STOPPED DSCNT. CTLR THEN TOLD US TO DSND AND MAINTAIN 5500 AND SHORTLY AFTER CLRED US FOR THE APCH TO RWY 24R. THE COPLT WAS CONFUSED AND DID NOT REACT BECAUSE HE FROZE UP FOR A COUPLE OF SECONDS. HE IS NEW TO FAR 121 OPS, NEW TO THE AIRLINE INDUSTRY AND NEW TO MODERN TECHNOLOGY. I BELIEVE THIS ALL CONTRIBUTED TO OVERWHELMING HIM TO THE POINT THAT HE JUST FROZE UP. I'M NOT SURE HOW WE CORRECT THIS PROBLEM, BUT I CAN SAY THAT THE INITIAL APCH SEGMENT IS VERY BUSY IN A 2-MAN COCKPIT AND IT IS VERY DIFFICULT TO PERFORM YOUR OWN DUTIES, SUPERVISE A NEW PLT AND REACT QUICKLY ENOUGH TO PREVENT PROBLEMS, ALL AT THE SAME TIME.

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.