B737-500 crew had a track deviation while on the aaces RNAV 1 departure at las.

Attributes
ACN	556348
Time
Date	200208
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : las.vortac
State Reference	NV
Altitude	msl single value : 6000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : l30.tracon
Operator	common carrier : air carrier
Make Model Name	B737-500
Operating Under FAR Part	Part 121
Navigation In Use	other
Route In Use	departure sid : aaces 1
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 196 flight time total : 14500 flight time type : 10850
ASRS Report	556348
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	non adherence : clearance non adherence : far non adherence : company policies non adherence : published procedure other anomaly other other spatial deviation
Independent Detector	atc equipment other atc equipment : radar other controllera
Resolutory Action	controller : issued new clearance controller : issued alert
Consequence	faa : reviewed incident with flight crew faa : investigated other
Supplementary
Problem Areas	FAA Company Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Deviation off course. We departed las for ZZZ. Departure was off runway 25R on the aaces RNAV 1 departure. The first officer was flying the departure with LNAV and autoplt selected as per company fom procedures. Approaching lodzy fix, the controller cleared us direct to idale fix and resume the aaces departure. I acknowledged the call and entered idale into the 'dir intc' prompt boxes on the FMC and then executed the change. I made this change quickly without confirming what I had selected. The first officer did not check the change either. The aircraft made a right turn (as expected) and rolled out approximately 170 degree heading and passing 6000 ft MSL. The controller asked where we were going and I replied 'direct idale on the aaces departure. He said we had turned too far, that idale was to our right. He then told us to continue on our heading, direct hitme (the fix after idale on the departure). I then realized that I had inadvertently selected hitme on the FMC instead of idale and that we had deviated off course. The controller stopped our climb and switched us to the next frequency where we were given a vector for spacing and told to call las departure upon arrival in ZZZ. Called las departure from ZZZ and the controller said there was no problem, they just wanted to know what happened. I told them it was operator error. In retrospect, if I had followed fom procedures and confirmed the change with the other crew member, we would have caught the error before executing the FMC.

Original NASA ASRS Text

Title: B737-500 CREW HAD A TRACK DEV WHILE ON THE AACES RNAV 1 DEP AT LAS.

Narrative: DEV OFF COURSE. WE DEPARTED LAS FOR ZZZ. DEP WAS OFF RWY 25R ON THE AACES RNAV 1 DEP. THE FO WAS FLYING THE DEP WITH LNAV AND AUTOPLT SELECTED AS PER COMPANY FOM PROCS. APCHING LODZY FIX, THE CTLR CLRED US DIRECT TO IDALE FIX AND RESUME THE AACES DEP. I ACKNOWLEDGED THE CALL AND ENTERED IDALE INTO THE 'DIR INTC' PROMPT BOXES ON THE FMC AND THEN EXECUTED THE CHANGE. I MADE THIS CHANGE QUICKLY WITHOUT CONFIRMING WHAT I HAD SELECTED. THE FO DID NOT CHK THE CHANGE EITHER. THE ACFT MADE A R TURN (AS EXPECTED) AND ROLLED OUT APPROX 170 DEG HDG AND PASSING 6000 FT MSL. THE CTLR ASKED WHERE WE WERE GOING AND I REPLIED 'DIRECT IDALE ON THE AACES DEP. HE SAID WE HAD TURNED TOO FAR, THAT IDALE WAS TO OUR R. HE THEN TOLD US TO CONTINUE ON OUR HDG, DIRECT HITME (THE FIX AFTER IDALE ON THE DEP). I THEN REALIZED THAT I HAD INADVERTENTLY SELECTED HITME ON THE FMC INSTEAD OF IDALE AND THAT WE HAD DEVIATED OFF COURSE. THE CTLR STOPPED OUR CLB AND SWITCHED US TO THE NEXT FREQ WHERE WE WERE GIVEN A VECTOR FOR SPACING AND TOLD TO CALL LAS DEP UPON ARR IN ZZZ. CALLED LAS DEP FROM ZZZ AND THE CTLR SAID THERE WAS NO PROB, THEY JUST WANTED TO KNOW WHAT HAPPENED. I TOLD THEM IT WAS OPERATOR ERROR. IN RETROSPECT, IF I HAD FOLLOWED FOM PROCS AND CONFIRMED THE CHANGE WITH THE OTHER CREW MEMBER, WE WOULD HAVE CAUGHT THE ERROR BEFORE EXECUTING THE FMC.

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.