Narrative:

At begin descent point; the captain had both his easi and ehsi experience signal generator failure. While running the procedure; I (flying on autopilot) was assigned an unusual crossing restriction for descent prior to fim. While busy getting the data into the navigation page for the crossing restriction; I failed to verify that the next restriction was in the box (cross sadde 12;000 ft; 280 KTS). After notifying ATC that the first restriction was too tight; they confirmed that we were fine and to continue to 12;000 ft. While continuing the descent I then realized that with all that was going on I had failed to put sadde restriction in and that would be tight. I still attempted to make the sadde restriction; however; before I could ask for relief; lax realized my altitude and gave me a west vector to avoid not making the crossing restriction. The captain finished with the procedure by now and was able to answer the approach controller's request to turn southeast (150 degrees is what he thought the controller gave us when in fact the controller gave us a 050 degree heading). Normally; once given a 270 degree heading; they typically give you a southeastern heading and then clear you direct smo. By the time the controller realized that we were south of the arrival; they asked why we were off course (heading 150 degrees) and told us to turn left 050 degrees immediately. We complied with his instructions and told him we had followed the 150 degree heading. The captain asked if we impacted any other traffic and were told 'no;' everything was fine. Supplemental information from acn 816986: right at top of descent; captain lost symbol generator; first officer had aircraft also gave ATC. Captain ran checklist and restored system and reported a maintenance request. During this time; ATC gave many crossings and the initial one was late; making it difficult. First officer advised and was provided relief. Rest of descent crossings difficult with 100 KT tailwind. ATC offered vector to 180 degree heading. I was fully back; got the next turn and read back heading 150 degrees. This took us off intended course. ATC wanted 050 degrees. ATC got excited but stated no conflict. First officer asked me what heading; and I had stated to him 150 degrees. I wish; since he didn't know; I had just verified with ATC. The entire descent was fast paced with the crossings coupled with irregularity and vectors and tailwind. As things sped up; the first officer elected to hand fly. This didn't help and I learned a lot. In retrospect; many things could have been managed by me; to include not caring about the symbol generator failure until we both knew that we were 'flying the aircraft.' thanks for this program.

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Original NASA ASRS Text

Title: B737 flight crew reported track and altitude deviations during SADDE6 arrival to LAX. Arrival is compounded by equipment malfunctions; 100 knot tailwinds; and a misheard heading assignment.

Narrative: At begin descent point; the Captain had both his EASI and EHSI experience signal generator failure. While running the procedure; I (flying on autopilot) was assigned an unusual crossing restriction for descent prior to FIM. While busy getting the data into the navigation page for the crossing restriction; I failed to verify that the next restriction was in the box (cross SADDE 12;000 FT; 280 KTS). After notifying ATC that the first restriction was too tight; they confirmed that we were fine and to continue to 12;000 FT. While continuing the descent I then realized that with all that was going on I had failed to put SADDE restriction in and that would be tight. I still attempted to make the SADDE restriction; however; before I could ask for relief; LAX realized my altitude and gave me a west vector to avoid not making the crossing restriction. The Captain finished with the procedure by now and was able to answer the Approach Controller's request to turn southeast (150 degrees is what he thought the Controller gave us when in fact the Controller gave us a 050 degree heading). Normally; once given a 270 degree heading; they typically give you a southeastern heading and then clear you direct SMO. By the time the Controller realized that we were south of the arrival; they asked why we were off course (heading 150 degrees) and told us to turn left 050 degrees immediately. We complied with his instructions and told him we had followed the 150 degree heading. The Captain asked if we impacted any other traffic and were told 'no;' everything was fine. Supplemental information from ACN 816986: Right at top of descent; Captain lost Symbol Generator; First Officer had aircraft also gave ATC. Captain ran checklist and restored system and reported a maintenance request. During this time; ATC gave many crossings and the initial one was late; making it difficult. First Officer advised and was provided relief. Rest of descent crossings difficult with 100 KT tailwind. ATC offered vector to 180 degree heading. I was fully back; got the next turn and read back heading 150 degrees. This took us off intended course. ATC wanted 050 degrees. ATC got excited but stated no conflict. First Officer asked me what heading; and I had stated to him 150 degrees. I wish; since he didn't know; I had just verified with ATC. The entire descent was fast paced with the crossings coupled with irregularity and vectors and tailwind. As things sped up; the First Officer elected to hand fly. This didn't help and I learned a lot. In retrospect; many things could have been managed by me; to include not caring about the Symbol Generator failure until we both knew that we were 'flying the aircraft.' Thanks for this program.

Data retrieved from NASA's ASRS site as of May 2009 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.