Narrative:

Takeoff weight: 89000 pounds. Clearance: loupe 9 sac transition direct rno, expect FL230. Takeoff and climb out were normal, however, aircraft was light and temperature was cool, so aircraft was climbing at a high rate. As we were leveling at 5000 ft as per departure procedure, we received clearance to 15000 ft unrestricted. While on the 120 degree heading and climbing through 9000 ft, clearance to proceed direct sjc VOR (at our discretion) cross the sjc VOR at or above 12000 ft and resume the departure, was received. We were about 3.5 mi from the sjc VOR when the captain (he was PF) turned towards the VOR. We were basically on top of the VOR and I believe he attempted to use LNAV, but it did not engage. I believe he then used raw data, which I had tuned in, to track outbound on the sjc 339 degree radial to dyblo intersection. When I saw that we were tracking outbound on the 339 degree radial and coming up on dyblo intersection, I tuned in sac VOR and the 191 degree radial inbound (011 degree course). Just a few moments before, we leveled at our cruise altitude of FL230. I looked down and saw that my CDI was centered at the 011 degree course at dyblo. I noted that we were on about a 360 degree heading or so, pretty close to where we should have been. At this point, I looked away and started to get my charts out for reno. When I looked up about 1 - 1 1/2 mins later, both the captain and I realized that we in fact had gone through the course at dyblo intersection. We were about 10-12 degrees northwest of the sac 191 degree radial. The captain immediately turned to correct the course. Within 15 seconds of our discovery, ZOA asked us if we were on a heading. I responded no and then he cleared us direct sac VOR. No other comments from ATC. I believe a factor that contributed to this was that the FMC did not realize that we had crossed the sjc on the departure and it gave us erroneous information for the climb and LNAV information. Also believe that LNAV was not engaged as we were in heading select when crossing dyblo, thus we did not turn at dyblo to track the sac 190 degree radial inbound. I learned that I should be more cognizant of the LNAV/autoplt modes, even if I'm not flying. Supplemental information from acn 570018: autoplt was on. Having trouble with the FMC, which would not go to sjc made me begin to troubleshoot the FMC and stop flying the airplane. It is company procedure for me (PF) to input the FMC with autoplt on. I am so ingrained with LNAV flying off of the FMC that when unable to engage it and forced to transition to heading and VOR/localizer, I failed to monitor raw data (radial/DME, first officer's, HSI, etc) and continued to monitor the FMC. I thought I was on progress page from sjc, next point dyblo, but was really on legs page, next fix sjc, then dyblo. Being the PF and trying to fix the FMC distraction me from flying the aircraft. I can't wait for -700 like moving map displays in the -300/-500's! Next time I have a problem with the FMC that requires me to transition to navigation with other than LNAV, I will direct the PNF to fix the FMC. Is this against our procedures? I guess a problem with programming the FMC should be handled like any other problem. PF -- fly, PNF -- fix it. That is what I will do next time.

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Original NASA ASRS Text

Title: SINGLE FMC EQUIPPED B737-300 FLC DEVIATED FROM CLRED ROUTING ON LOUPE DEP, SACRAMENTO TRANSITION FROM SJC.

Narrative: TKOF WT: 89000 LBS. CLRNC: LOUPE 9 SAC TRANSITION DIRECT RNO, EXPECT FL230. TKOF AND CLBOUT WERE NORMAL, HOWEVER, ACFT WAS LIGHT AND TEMP WAS COOL, SO ACFT WAS CLBING AT A HIGH RATE. AS WE WERE LEVELING AT 5000 FT AS PER DEP PROC, WE RECEIVED CLRNC TO 15000 FT UNRESTRICTED. WHILE ON THE 120 DEG HDG AND CLBING THROUGH 9000 FT, CLRNC TO PROCEED DIRECT SJC VOR (AT OUR DISCRETION) CROSS THE SJC VOR AT OR ABOVE 12000 FT AND RESUME THE DEP, WAS RECEIVED. WE WERE ABOUT 3.5 MI FROM THE SJC VOR WHEN THE CAPT (HE WAS PF) TURNED TOWARDS THE VOR. WE WERE BASICALLY ON TOP OF THE VOR AND I BELIEVE HE ATTEMPTED TO USE LNAV, BUT IT DID NOT ENGAGE. I BELIEVE HE THEN USED RAW DATA, WHICH I HAD TUNED IN, TO TRACK OUTBOUND ON THE SJC 339 DEG RADIAL TO DYBLO INTXN. WHEN I SAW THAT WE WERE TRACKING OUTBOUND ON THE 339 DEG RADIAL AND COMING UP ON DYBLO INTXN, I TUNED IN SAC VOR AND THE 191 DEG RADIAL INBOUND (011 DEG COURSE). JUST A FEW MOMENTS BEFORE, WE LEVELED AT OUR CRUISE ALT OF FL230. I LOOKED DOWN AND SAW THAT MY CDI WAS CTRED AT THE 011 DEG COURSE AT DYBLO. I NOTED THAT WE WERE ON ABOUT A 360 DEG HDG OR SO, PRETTY CLOSE TO WHERE WE SHOULD HAVE BEEN. AT THIS POINT, I LOOKED AWAY AND STARTED TO GET MY CHARTS OUT FOR RENO. WHEN I LOOKED UP ABOUT 1 - 1 1/2 MINS LATER, BOTH THE CAPT AND I REALIZED THAT WE IN FACT HAD GONE THROUGH THE COURSE AT DYBLO INTXN. WE WERE ABOUT 10-12 DEGS NW OF THE SAC 191 DEG RADIAL. THE CAPT IMMEDIATELY TURNED TO CORRECT THE COURSE. WITHIN 15 SECONDS OF OUR DISCOVERY, ZOA ASKED US IF WE WERE ON A HDG. I RESPONDED NO AND THEN HE CLRED US DIRECT SAC VOR. NO OTHER COMMENTS FROM ATC. I BELIEVE A FACTOR THAT CONTRIBUTED TO THIS WAS THAT THE FMC DID NOT REALIZE THAT WE HAD CROSSED THE SJC ON THE DEP AND IT GAVE US ERRONEOUS INFO FOR THE CLB AND LNAV INFO. ALSO BELIEVE THAT LNAV WAS NOT ENGAGED AS WE WERE IN HDG SELECT WHEN XING DYBLO, THUS WE DID NOT TURN AT DYBLO TO TRACK THE SAC 190 DEG RADIAL INBOUND. I LEARNED THAT I SHOULD BE MORE COGNIZANT OF THE LNAV/AUTOPLT MODES, EVEN IF I'M NOT FLYING. SUPPLEMENTAL INFO FROM ACN 570018: AUTOPLT WAS ON. HAVING TROUBLE WITH THE FMC, WHICH WOULD NOT GO TO SJC MADE ME BEGIN TO TROUBLESHOOT THE FMC AND STOP FLYING THE AIRPLANE. IT IS COMPANY PROC FOR ME (PF) TO INPUT THE FMC WITH AUTOPLT ON. I AM SO INGRAINED WITH LNAV FLYING OFF OF THE FMC THAT WHEN UNABLE TO ENGAGE IT AND FORCED TO TRANSITION TO HDG AND VOR/LOC, I FAILED TO MONITOR RAW DATA (RADIAL/DME, FO'S, HSI, ETC) AND CONTINUED TO MONITOR THE FMC. I THOUGHT I WAS ON PROGRESS PAGE FROM SJC, NEXT POINT DYBLO, BUT WAS REALLY ON LEGS PAGE, NEXT FIX SJC, THEN DYBLO. BEING THE PF AND TRYING TO FIX THE FMC DISTR ME FROM FLYING THE ACFT. I CAN'T WAIT FOR -700 LIKE MOVING MAP DISPLAYS IN THE -300/-500'S! NEXT TIME I HAVE A PROB WITH THE FMC THAT REQUIRES ME TO TRANSITION TO NAV WITH OTHER THAN LNAV, I WILL DIRECT THE PNF TO FIX THE FMC. IS THIS AGAINST OUR PROCS? I GUESS A PROB WITH PROGRAMMING THE FMC SHOULD BE HANDLED LIKE ANY OTHER PROB. PF -- FLY, PNF -- FIX IT. THAT IS WHAT I WILL DO NEXT TIME.

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.