Altitude deviation on STAR. Crossing restriction not met. Clearance misinterpreted.

Attributes
ACN	113574
Time
Date	198906
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : pmd airport : ont
State Reference	CA
Altitude	msl bound lower : 13000 msl bound upper : 14000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	cruise other cruise other descent other
Route In Use	arrival other arrival star : star enroute airway : zla
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 200 flight time total : 11000 flight time type : 700
ASRS Report	113574
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 130 flight time total : 11800 flight time type : 222
ASRS Report	113586
Events
Anomaly	altitude deviation : crossing restriction not met non adherence : clearance non adherence : published procedure other spatial deviation
Independent Detector	other controllera
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	Pilot Deviation other
Situations
ATC Facility	procedure or policy : unspecified

Narrative:

While tracking out the 104 degree radial of palmdale (pmd/114.5) we were given descent clearance to cross majek intersection at 14,000' MSL. As we were approaching majek (pmd 104 degree/30 NM) the controller (ZLA) revised the clearance to 'maintain 13,000', slow to 250 KIAS before leaving 14,000' MSL.' we read this back and believed it cancelled the cross majek at 14,000' restriction. The revised clearance was received approximately 25 DME from palmdale on the 104 degree radial. We leveled (copilot flying) at 14,000', slowed to 250 KTS, and descended to 13,000 by the 30 DME fix. The controller called us at majek and asked our altitude. We replied 13,000' and he was surprised and said our clearance had been to cross majek at 14,000'. We said we read back a revised clearance to 13,000. He said no. When I asked if there had been a traffic conflict the controller said he didn't know, he was checking, call ontario approach control now. We thought the revised clearance to a lower altitude had cancelled the previous crossing restriction at majek.

Original NASA ASRS Text

Title: ALT DEVIATION ON STAR. CROSSING RESTRICTION NOT MET. CLRNC MISINTERPRETED.

Narrative: WHILE TRACKING OUT THE 104 DEG RADIAL OF PALMDALE (PMD/114.5) WE WERE GIVEN DSCNT CLRNC TO CROSS MAJEK INTXN AT 14,000' MSL. AS WE WERE APCHING MAJEK (PMD 104 DEG/30 NM) THE CTLR (ZLA) REVISED THE CLRNC TO 'MAINTAIN 13,000', SLOW TO 250 KIAS BEFORE LEAVING 14,000' MSL.' WE READ THIS BACK AND BELIEVED IT CANCELLED THE CROSS MAJEK AT 14,000' RESTRICTION. THE REVISED CLRNC WAS RECEIVED APPROX 25 DME FROM PALMDALE ON THE 104 DEG RADIAL. WE LEVELED (COPLT FLYING) AT 14,000', SLOWED TO 250 KTS, AND DESCENDED TO 13,000 BY THE 30 DME FIX. THE CTLR CALLED US AT MAJEK AND ASKED OUR ALT. WE REPLIED 13,000' AND HE WAS SURPRISED AND SAID OUR CLRNC HAD BEEN TO CROSS MAJEK AT 14,000'. WE SAID WE READ BACK A REVISED CLRNC TO 13,000. HE SAID NO. WHEN I ASKED IF THERE HAD BEEN A TFC CONFLICT THE CTLR SAID HE DIDN'T KNOW, HE WAS CHECKING, CALL ONTARIO APCH CTL NOW. WE THOUGHT THE REVISED CLRNC TO A LOWER ALT HAD CANCELLED THE PREVIOUS XING RESTRICTION AT MAJEK.

Data retrieved from NASA's ASRS site as of August 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.