A course deviation on the tragr RNAV 2 arrival to las, nv.

Attributes
ACN	572584
Time
Date	200302
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	intersection : las
State Reference	NV
Altitude	msl single value : 14000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : l30.tracon
Operator	common carrier : air carrier
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : intermediate altitude
Route In Use	arrival star : tragr rnav
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : commercial pilot : instrument
Experience	flight time last 90 days : 43 flight time total : 7000 flight time type : 400
ASRS Report	572584
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 250 flight time total : 6000 flight time type : 4000
ASRS Report	572581
Events
Anomaly	aircraft equipment problem : less severe non adherence : published procedure non adherence : clearance other anomaly other other spatial deviation
Independent Detector	other controllerb
Resolutory Action	controller : issued advisory controller : issued new clearance
Consequence	faa : reviewed incident with flight crew other
Supplementary
Problem Areas	Company Aircraft ATC Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Deviation from cleared routing. We were on the tragr RNAV 2 arrival into las with the autoplt engaged. Sometime after tragr, the controller asked us if we were going direct shand which is a fix on the ILS runway 25L approach. We looked at the FMS and realized that we were, even though we should have been going to ipumy. The controller's response caused me to look at the captain and say 'it sounds like this has happened before.' the controller then said that ipumy has been 'dropping out' for us (company). After a vector and then proceeding direct to bld, we landed uneventfully. We had no traffic conflicts from our error. The captain called ATC when we landed and was told that we were the 7TH company crew to do this same thing today and that they had notified our company about the problem. ATC said they were really just trying to find out the facts of what was going on and didn't seem too bothered about our deviation. I am not 100% convinced that the last 3 fixes on the arrival were not at some time in the FMS and that they dropped out. I say this because while in cruise I began to verify that the altitude and speed crossing restrs for the arrival were entered in the legs page. The captain remembered seeing me check them. All 3 fixes that we missed have altitude or speed restrs. However, I cannot recall specifically verifying each and every one. If I did not, it was due to a distraction because my normal routine would have had me check all of them and I would have, therefore, noticed these fixes were not in the FMS. Regardless, I should have monitored the FMS more closely and verified after crossing each fix that we were proceeding to the next one. As a side note, if the controller had let us descend via the published arrival instead of issuing us altitudes and speeds himself we would have noticed ipumy was not in the FMS. ATC seems to do this regularly. Their restrs are usually very close to what is on the published STAR so why not just let us fly what is published? Careful monitoring of our progress on the arrival would have prevented this from happening and I will be more vigilant from now on.

Original NASA ASRS Text

Title: A COURSE DEV ON THE TRAGR RNAV 2 ARR TO LAS, NV.

Narrative: DEV FROM CLRED ROUTING. WE WERE ON THE TRAGR RNAV 2 ARR INTO LAS WITH THE AUTOPLT ENGAGED. SOMETIME AFTER TRAGR, THE CTLR ASKED US IF WE WERE GOING DIRECT SHAND WHICH IS A FIX ON THE ILS RWY 25L APCH. WE LOOKED AT THE FMS AND REALIZED THAT WE WERE, EVEN THOUGH WE SHOULD HAVE BEEN GOING TO IPUMY. THE CTLR'S RESPONSE CAUSED ME TO LOOK AT THE CAPT AND SAY 'IT SOUNDS LIKE THIS HAS HAPPENED BEFORE.' THE CTLR THEN SAID THAT IPUMY HAS BEEN 'DROPPING OUT' FOR US (COMPANY). AFTER A VECTOR AND THEN PROCEEDING DIRECT TO BLD, WE LANDED UNEVENTFULLY. WE HAD NO TFC CONFLICTS FROM OUR ERROR. THE CAPT CALLED ATC WHEN WE LANDED AND WAS TOLD THAT WE WERE THE 7TH COMPANY CREW TO DO THIS SAME THING TODAY AND THAT THEY HAD NOTIFIED OUR COMPANY ABOUT THE PROB. ATC SAID THEY WERE REALLY JUST TRYING TO FIND OUT THE FACTS OF WHAT WAS GOING ON AND DIDN'T SEEM TOO BOTHERED ABOUT OUR DEV. I AM NOT 100% CONVINCED THAT THE LAST 3 FIXES ON THE ARR WERE NOT AT SOME TIME IN THE FMS AND THAT THEY DROPPED OUT. I SAY THIS BECAUSE WHILE IN CRUISE I BEGAN TO VERIFY THAT THE ALT AND SPD XING RESTRS FOR THE ARR WERE ENTERED IN THE LEGS PAGE. THE CAPT REMEMBERED SEEING ME CHK THEM. ALL 3 FIXES THAT WE MISSED HAVE ALT OR SPD RESTRS. HOWEVER, I CANNOT RECALL SPECIFICALLY VERIFYING EACH AND EVERY ONE. IF I DID NOT, IT WAS DUE TO A DISTR BECAUSE MY NORMAL ROUTINE WOULD HAVE HAD ME CHK ALL OF THEM AND I WOULD HAVE, THEREFORE, NOTICED THESE FIXES WERE NOT IN THE FMS. REGARDLESS, I SHOULD HAVE MONITORED THE FMS MORE CLOSELY AND VERIFIED AFTER XING EACH FIX THAT WE WERE PROCEEDING TO THE NEXT ONE. AS A SIDE NOTE, IF THE CTLR HAD LET US DSND VIA THE PUBLISHED ARR INSTEAD OF ISSUING US ALTS AND SPDS HIMSELF WE WOULD HAVE NOTICED IPUMY WAS NOT IN THE FMS. ATC SEEMS TO DO THIS REGULARLY. THEIR RESTRS ARE USUALLY VERY CLOSE TO WHAT IS ON THE PUBLISHED STAR SO WHY NOT JUST LET US FLY WHAT IS PUBLISHED? CAREFUL MONITORING OF OUR PROGRESS ON THE ARR WOULD HAVE PREVENTED THIS FROM HAPPENING AND I WILL BE MORE VIGILANT FROM NOW 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.