B737 crew descends early approaching queny on the eagul 1 into phx due to navigation problem.

Attributes
ACN	717557
Time
Date	200611
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : phx.airport
State Reference	AZ
Altitude	msl bound lower : 7500 msl bound upper : 8000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : p50.tracon
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	descent : approach descent : intermediate altitude
Route In Use	arrival star : eagul
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Experience	flight time last 90 days : 200 flight time total : 5000 flight time type : 500
ASRS Report	717557
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 189
ASRS Report	717410
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : excursion from assigned altitude non adherence : published procedure
Independent Detector	other controllera other flight crewa
Resolutory Action	controller : issued new clearance flight crew : returned to assigned altitude
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

We were cleared to descend via eagul one RNAV arrival; flight to phx. We were level at 8000 ft 210 knots at queny; as altitude hold was captured; we selected 6000 ft for the next restriction at hiney. As both pilots saw queny pass in the legs page the captain started down for 6000 ft. Next ATC called and asked why we were descending. We both looked down at the box and saw queny back in the box and we were 2.3 miles to go. We were at 7400 ft at this time and climbed back to 8000 ft. We asked ATC to confirm our position. We were then given a vector off the STAR and a descent to 6000 ft. We landed with no problems and the captain made a logbook entry with a navigation problem. Double check the canned flight plans and make sure the points are correct. Pilots cross tune radials and DME if able.supplemental information from acn 717410: suspect the database is corrupt of the navigation system.

Original NASA ASRS Text

Title: B737 CREW DESCENDS EARLY APCHING QUENY ON THE EAGUL 1 INTO PHX DUE TO NAV PROB.

Narrative: WE WERE CLEARED TO DESCEND VIA EAGUL ONE RNAV ARRIVAL; FLIGHT TO PHX. WE WERE LEVEL AT 8000 FT 210 KNOTS AT QUENY; AS ALTITUDE HOLD WAS CAPTURED; WE SELECTED 6000 FT FOR THE NEXT RESTRICTION AT HINEY. AS BOTH PILOTS SAW QUENY PASS IN THE LEGS PAGE THE CAPTAIN STARTED DOWN FOR 6000 FT. NEXT ATC CALLED AND ASKED WHY WE WERE DESCENDING. WE BOTH LOOKED DOWN AT THE BOX AND SAW QUENY BACK IN THE BOX AND WE WERE 2.3 MILES TO GO. WE WERE AT 7400 FT AT THIS TIME AND CLIMBED BACK TO 8000 FT. WE ASKED ATC TO CONFIRM OUR POSITION. WE WERE THEN GIVEN A VECTOR OFF THE STAR AND A DESCENT TO 6000 FT. WE LANDED WITH NO PROBLEMS AND THE CAPTAIN MADE A LOGBOOK ENTRY WITH A NAV PROBLEM. DOUBLE CHECK THE CANNED FLIGHT PLANS AND MAKE SURE THE POINTS ARE CORRECT. PILOTS CROSS TUNE RADIALS AND DME IF ABLE.SUPPLEMENTAL INFO FROM ACN 717410: SUSPECT THE DATABASE IS CORRUPT OF THE NAV SYSTEM.

Data retrieved from NASA's ASRS site as of January 2009 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.