Flight crew of a B757 misprogrammed the FMC causing a slower descent on a STAR arrival than required by ATC. ARTCC was notified of the problem prior to the fix resulting in ATC vectoring off course until aircraft had appropriately descended before the crossing fix.

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Attributes
ACN	400590
Time
Date	199804
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : fqm
State Reference	PA
Altitude	msl bound lower : 19000 msl bound upper : 19000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zny tower : rno
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent other
Route In Use	arrival other arrival star : star enroute airway : zny
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 250 flight time total : 19000 flight time type : 500
ASRS Report	400590
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	altitude deviation : crossing restriction not met non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Received clearance to cross hayed intersection at FL190. FMS (CDU) originally had hayed at FL180 programmed. PF put in new clearance in CDU but line selected penns intersection instead of hayed. Penns is further away than hayed intersection. Because it was a higher altitude at a fix further away from original programming, the box (FMC) deleted the hayed at FL180 restr and now computed penns at FL190 for top of descent point. About 10 mi from hayed intersection, captain noticed the error while in a descent (aircraft programmed to cross penns at FL190). Immediately called ATC and advised. Was given a turn off airway to facilitate descent, then turned back to original course and resumed normal navigation. Error was made by not doublechking line entry and new crossing restr and second error was made by not checking line 1R of CDU on 'descent page' to see what the top of descent point was being computed on.

Original NASA ASRS Text

Title: FLC OF A B757 MISPROGRAMMED THE FMC CAUSING A SLOWER DSCNT ON A STAR ARR THAN REQUIRED BY ATC. ARTCC WAS NOTIFIED OF THE PROB PRIOR TO THE FIX RESULTING IN ATC VECTORING OFF COURSE UNTIL ACFT HAD APPROPRIATELY DSNDED BEFORE THE XING FIX.

Narrative: RECEIVED CLRNC TO CROSS HAYED INTXN AT FL190. FMS (CDU) ORIGINALLY HAD HAYED AT FL180 PROGRAMMED. PF PUT IN NEW CLRNC IN CDU BUT LINE SELECTED PENNS INTXN INSTEAD OF HAYED. PENNS IS FURTHER AWAY THAN HAYED INTXN. BECAUSE IT WAS A HIGHER ALT AT A FIX FURTHER AWAY FROM ORIGINAL PROGRAMMING, THE BOX (FMC) DELETED THE HAYED AT FL180 RESTR AND NOW COMPUTED PENNS AT FL190 FOR TOP OF DSCNT POINT. ABOUT 10 MI FROM HAYED INTXN, CAPT NOTICED THE ERROR WHILE IN A DSCNT (ACFT PROGRAMMED TO CROSS PENNS AT FL190). IMMEDIATELY CALLED ATC AND ADVISED. WAS GIVEN A TURN OFF AIRWAY TO FACILITATE DSCNT, THEN TURNED BACK TO ORIGINAL COURSE AND RESUMED NORMAL NAV. ERROR WAS MADE BY NOT DOUBLECHKING LINE ENTRY AND NEW XING RESTR AND SECOND ERROR WAS MADE BY NOT CHKING LINE 1R OF CDU ON 'DSCNT PAGE' TO SEE WHAT THE TOP OF DSCNT POINT WAS BEING COMPUTED ON.

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.