B737-300 flight crew has altitude deviation during published arrival to las.

Attributes
ACN	557163
Time
Date	200208
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	intersection : lynsy
State Reference	NV
Altitude	msl bound lower : 10000 msl bound upper : 12000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : l30.tracon
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	arrival star : lynsy rnav
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : multi engine pilot : instrument
Experience	flight time last 90 days : 190 flight time total : 7500 flight time type : 3500
ASRS Report	557163
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 4500 flight time type : 4500
ASRS Report	557441
Events
Anomaly	altitude deviation : overshoot altitude deviation : crossing restriction not met non adherence : published procedure non adherence : clearance
Independent Detector	other controllerb
Resolutory Action	none taken : detected after the fact
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While descending into las, approach told us to descend to and maintain 10000 ft via the lynsy arrival. The first fix was lynsy and the altitude was 12000 ft because we were told to descend to a hard altitude of 10000 ft. It was my understanding that 10000 ft was the altitude they (las approach) wanted us at. When level at 10000 ft, las approach asked us what altitude we were at and what we were assigned. We responded with the above, and were given a phone number to call when we landed. At no time were any aircraft in our area. We called and explained to approach what we thought the clearance meant, and they said there would be no action against us, that they wanted to straighten this out to avoid future deviations. I think ATC could have been clrer and more concise by stating descend to lynsy at 12000 ft, and then descend and maintain 10000 ft.

Original NASA ASRS Text

Title: B737-300 FLC HAS ALTDEV DURING PUBLISHED ARR TO LAS.

Narrative: WHILE DSNDING INTO LAS, APCH TOLD US TO DSND TO AND MAINTAIN 10000 FT VIA THE LYNSY ARR. THE FIRST FIX WAS LYNSY AND THE ALT WAS 12000 FT BECAUSE WE WERE TOLD TO DSND TO A HARD ALT OF 10000 FT. IT WAS MY UNDERSTANDING THAT 10000 FT WAS THE ALT THEY (LAS APCH) WANTED US AT. WHEN LEVEL AT 10000 FT, LAS APCH ASKED US WHAT ALT WE WERE AT AND WHAT WE WERE ASSIGNED. WE RESPONDED WITH THE ABOVE, AND WERE GIVEN A PHONE NUMBER TO CALL WHEN WE LANDED. AT NO TIME WERE ANY ACFT IN OUR AREA. WE CALLED AND EXPLAINED TO APCH WHAT WE THOUGHT THE CLRNC MEANT, AND THEY SAID THERE WOULD BE NO ACTION AGAINST US, THAT THEY WANTED TO STRAIGHTEN THIS OUT TO AVOID FUTURE DEVS. I THINK ATC COULD HAVE BEEN CLRER AND MORE CONCISE BY STATING DSND TO LYNSY AT 12000 FT, AND THEN DSND AND MAINTAIN 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.