Narrative:

I was pm (pilot monitoring) on flight to lax. Set up for DIRBY1 arrival per filed flight plan. During cruise reroute to lax via burgl ZUUMA2 arrival. Set up arrival and ILS 6R per ATIS. Then briefed before descent. Went to lavatory and readied galley for descent. When out of the flight deck; PF (pilot flying) received another reroute of direct burgl IRNMN1 arrival and ILS 25L. PF selected arrival and approach. When I returned to flight deck PF advised me of the change then I preceded to verify the arrival fixes and constraints. At that time; cleared descent via IRNMN1 except maintain 12;000 feet. All constraints were being met as expected with aircraft in LNAV/VNAV and VNAV path annunciated. Then cleared descent via to 6;000 feet; altitude was set and verified. With aircraft in same modes and VNAV path and vpi (vertical path indicator) indicating right on path aircraft passed symon (13000B/11000A) at approximately 12;800 feet and started shallow descent with bayst (9000A) as next fix. ATC then asked if we were descending via the arrival. With LNAV/VNAV; VNAV path and vpi all indicated on profile; I responded 'yes [approximately] 12;400 via IRNMN1 to 6;000.' since ATC asked it prompted us to look into the position of the aircraft even with all indications showing us on profile. After figuring out we were going to be high at juuse (9000B/8000A) from time and distance. PF put in speed brakes and pulled power back to help aircraft descend faster. Aircraft still tried to level off around 12;000 ft even with VNAV path and 6;000 feet verified on MCP (mode control panel) and pfd. At this time I took over controls; disengaged auto pilot and auto throttles and forced aircraft down to try and get on proper profile. With command bars trying to hold 12;000 feet and vpi still showing on path; selected flch (flight level change). Missed juuse high by approximately 1;500 feet. ATC asked us our altitude and can't quite remember what first officer responded with. Then after response ATC cleared us to 2;500 feet and no speed restrictions. I continued to descend making that latter constraints at end of arrival. Once on a normal path; re-automated aircraft and transferred controls back to first officer. We then were assigned heading and cleared for approach. We kept the cockpit sterile and did not discuss or talk about anything except for proper callouts for approach. Did a course fix intercept and completed rest of flight normally and successfully.after getting to the gate we then went over everything to figure out why the automation did not do what we expected. After realizing that the approach was entered with a transition; figured that was the problem. On the nfd (navigational flight display) and in the FMC the approach looked normal as always; a straight line of all the fixes. What I did not notice; that it actually included a transition straight out along the line. It still had a route discontinuity between the arrival and the approach and vectors at the end of the arrival as LNAV worked perfectly. However; there is a small caption on the approach chart near the transition of crcus 14000B/12000A. Apparently even with the route discontinued; VNAV looked through all the other fixes; route discontinuity and tried and honor that 12000A. Being a little rushed and making sure we had all of the proper constraints on our third arrival programmed; I feel I neglected the approach a bit knowing there was a route discontinuity; it looked normal and we would be doing a course fix intercept somewhere near hunda after a heading was assigned. I should have paid more attention to the fixes in the FMC and made sure krain was last fix on the approach side or if I double checked the route page I possibly could have noticed.

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Original NASA ASRS Text

Title: B747 Captain reported a missed altitude restriction with VNAV PATH correctly programmed; verified; and coupled.

Narrative: I was PM (Pilot Monitoring) on flight to LAX. Set up for DIRBY1 arrival per filed flight plan. During cruise reroute to LAX via BURGL ZUUMA2 arrival. Set up arrival and ILS 6R per ATIS. Then briefed before descent. Went to lavatory and readied galley for descent. When out of the flight deck; PF (Pilot Flying) received another reroute of direct BURGL IRNMN1 arrival and ILS 25L. PF selected arrival and approach. When I returned to flight deck PF advised me of the change then I preceded to verify the Arrival fixes and constraints. At that time; cleared descent via IRNMN1 except maintain 12;000 feet. All constraints were being met as expected with aircraft in LNAV/VNAV and VNAV PATH annunciated. Then cleared descent via to 6;000 feet; altitude was set and verified. With aircraft in same modes and VNAV PATH and VPI (Vertical Path Indicator) indicating right on path aircraft passed SYMON (13000B/11000A) at approximately 12;800 feet and started shallow descent with BAYST (9000A) as next fix. ATC then asked if we were descending via the arrival. With LNAV/VNAV; VNAV PATH and VPI all indicated on profile; I responded 'yes [approximately] 12;400 via IRNMN1 to 6;000.' Since ATC asked it prompted us to look into the position of the aircraft even with all indications showing us on profile. After figuring out we were going to be high at JUUSE (9000B/8000A) from time and distance. PF put in speed brakes and pulled power back to help aircraft descend faster. Aircraft still tried to level off around 12;000 ft even with VNAV PATH and 6;000 feet verified on MCP (Mode Control Panel) and PFD. At this time I took over controls; disengaged auto pilot and auto throttles and forced aircraft down to try and get on proper profile. With command bars trying to hold 12;000 feet and VPI still showing on path; selected FLCH (Flight Level Change). Missed JUUSE high by approximately 1;500 feet. ATC asked us our altitude and can't quite remember what First Officer responded with. Then after response ATC cleared us to 2;500 feet and no speed restrictions. I continued to descend making that latter constraints at end of arrival. Once on a normal path; re-automated aircraft and transferred controls back to First Officer. We then were assigned heading and cleared for approach. We kept the cockpit sterile and did not discuss or talk about anything except for proper callouts for approach. Did a course fix intercept and completed rest of flight normally and successfully.After getting to the gate we then went over everything to figure out why the automation did not do what we expected. After realizing that the approach was entered with a transition; figured that was the problem. On the NFD (Navigational Flight Display) and in the FMC the approach looked normal as always; a straight line of all the fixes. What I did not notice; that it actually included a transition straight out along the line. It still had a route discontinuity between the arrival and the approach and vectors at the end of the arrival as LNAV worked perfectly. However; there is a small caption on the approach chart near the transition of CRCUS 14000B/12000A. Apparently even with the route discontinued; VNAV looked through all the other fixes; route discontinuity and tried and honor that 12000A. Being a little rushed and making sure we had all of the proper constraints on our third arrival programmed; I feel I neglected the approach a bit knowing there was a route discontinuity; it looked normal and we would be doing a course fix intercept somewhere near HUNDA after a heading was assigned. I should have paid more attention to the fixes in the FMC and made sure KRAIN was last fix on the approach side or if I double checked the ROUTE page I possibly could have noticed.

Data retrieved from NASA's ASRS site 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.