Captain descends on approach without clearance.

Attributes
ACN	294764
Time
Date	199501
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : lax
State Reference	CA
Altitude	msl bound lower : 19000 msl bound upper : 22000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zla
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent other
Route In Use	arrival other arrival star : star
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 10000 flight time type : 2200
ASRS Report	294764
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	294957
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : published procedure non adherence : clearance other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was the first officer on this flight and was talking with ATC. The captain was flying the aircraft. We were proceeding direct to civet int, cleared to descend to FL220. We leveled at FL220 and I asked the controller if we were going to get the reedr 3 arrival. The ATIS said lax was landing on 7R and 6L. This is different as lax lands traffic most of the time on 25L and 24R. The controller cleared us for the reedr 3 arrival and to maintain FL220. I was loading the FMS for the reedr 3 arrival, ATC gave us several speed changes and TA's. Several mins later, ATC asked what our assigned altitude was. I saw that we were descending and that FL190 was in our altitude set window on the FMS panel. The captain said that he thought we had been cleared to FL190. I don't recall that. The controller said we were clear of traffic and to descend to 14000 ft. I think the contributing factor to this was not knowing what arrival to expect until we were almost at civet intersection. Most other airports give what arrs to expect on the ATIS. That way the arrival can be loaded into the FMS well in advance. We were very busy in the cockpit when this happened, changing speed, altitude headings, looking for traffic and loading data into the FMS for an arrival which is rarely used.

Original NASA ASRS Text

Title: CAPT DSNDS ON APCH WITHOUT CLRNC.

Narrative: I WAS THE FO ON THIS FLT AND WAS TALKING WITH ATC. THE CAPT WAS FLYING THE ACFT. WE WERE PROCEEDING DIRECT TO CIVET INT, CLRED TO DSND TO FL220. WE LEVELED AT FL220 AND I ASKED THE CTLR IF WE WERE GOING TO GET THE REEDR 3 ARR. THE ATIS SAID LAX WAS LNDG ON 7R AND 6L. THIS IS DIFFERENT AS LAX LANDS TFC MOST OF THE TIME ON 25L AND 24R. THE CTLR CLRED US FOR THE REEDR 3 ARR AND TO MAINTAIN FL220. I WAS LOADING THE FMS FOR THE REEDR 3 ARR, ATC GAVE US SEVERAL SPD CHANGES AND TA'S. SEVERAL MINS LATER, ATC ASKED WHAT OUR ASSIGNED ALT WAS. I SAW THAT WE WERE DSNDING AND THAT FL190 WAS IN OUR ALT SET WINDOW ON THE FMS PANEL. THE CAPT SAID THAT HE THOUGHT WE HAD BEEN CLRED TO FL190. I DON'T RECALL THAT. THE CTLR SAID WE WERE CLR OF TFC AND TO DSND TO 14000 FT. I THINK THE CONTRIBUTING FACTOR TO THIS WAS NOT KNOWING WHAT ARR TO EXPECT UNTIL WE WERE ALMOST AT CIVET INTXN. MOST OTHER ARPTS GIVE WHAT ARRS TO EXPECT ON THE ATIS. THAT WAY THE ARR CAN BE LOADED INTO THE FMS WELL IN ADVANCE. WE WERE VERY BUSY IN THE COCKPIT WHEN THIS HAPPENED, CHANGING SPD, ALT HDGS, LOOKING FOR TFC AND LOADING DATA INTO THE FMS FOR AN ARR WHICH IS RARELY USED.

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.