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|
Attributes | |
ACN | 1694917 |
Time | |
Date | 201910 |
Local Time Of Day | 1201-1800 |
Place | |
Locale Reference | ZLA.ARTCC |
State Reference | CA |
Environment | |
Light | Daylight |
Aircraft 1 | |
Make Model Name | B747-800 Advanced |
Operating Under FAR Part | Part 121 |
Flight Phase | Cruise |
Flight Plan | IFR |
Component | |
Aircraft Component | Air Data Computer |
Person 1 | |
Function | Captain Pilot Not Flying |
Qualification | Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine |
Events | |
Anomaly | Aircraft Equipment Problem Less Severe Deviation - Procedural Published Material / Policy |
Narrative:
Approximately 30 minutes from top of descent at FL380 flying into lax near ZZZ the EICAS message: 'air data computer right' came on. The first officer (first officer) was flying the aircraft. I pulled up the electronic checklist and read aloud the condition and objective and the first three items of the checklist which are to turn off the autopilot; ats; and flight directors. At this point the first officer and I discussed duties briefly (i.e.; first officer fly while captain runs the checklist). When the first officer felt comfortable; we turned everything off and the first officer was hand flying just off of raw data. The checklist then ask if the EICAS message: is air data computer center message shown; I answered no; then the next step in the checklist is 'center air data selector... On right'. I looked all over the instrument panel for center air data selector; could not find it. This is where I regressed to older aircraft I have flown and thought 'center air data was the same as 'central air data computer' (CADC) and flying mostly the -400 I was also thinking we had only 2 air data computer's when in fact we had 3 (747-8). So I took control of the aircraft and told the first officer to position his air data computer source selector to right. This is where things really got bad. By putting the first officer's source selector to right I in fact took away his pfd. I handed control back to the first officer as I continued to run the checklist. It was at this time the first officer sounded off loudly and clearly the 'he had nothing 'on his side. I was trying to get through the checklist and did not look at his pfd. I basically shut him down (thinking he still had raw data on his side) and told him to let me finish the checklist. The first officer at this time is flying cross cockpit off of raw data on the captains instruments that were working satisfactorily. Finally after several overrides on the checklist we came to first officer air data computer source selector... Left; the first officer accomplished this and the first officer's pfd was restored. At no time did we deviate from assigned altitude or routing. We re-automated and advised ATC we were unable rvsm; ATC issued 15 degree left turn and a minute later instructed a descent to 28000 ft.; after the descent we finished the remainder of the flight uneventfully.the crew makeup was two captains and one first officer. Since data was good on my side I should have been the one flying the aircraft. The other captain was present trying to help out with the hard copy checklist. He gave valuable inputs but I was running the show. The smart thing to have done would have been to let the other captain and the first officer run the checklist while I fly since there were no faults on my side. Putting that aside; when the first officer was trying to tell me he had nothing on his side and had I stopped and analyzed our situation; maybe I would have taken over flying duties and allowed this very capable first officer to run the checklist. I regretfully did not. The other thing is the center air data switch is on the overhead panel. It wasn't until after landing the other captain realized this and told me. It would have been helpful if the checklist read center air data selector (on overhead panel) right. Since this switch is never or rarely talked about or trained on.
Original NASA ASRS Text
Title: B747 Captain reported that an EICAS message of ADC RIGHT occurred and that the crew had difficulty locating the ADC switch and performing the checklist sequence.
Narrative: Approximately 30 minutes from top of descent at FL380 flying into LAX near ZZZ the EICAS MSG: 'ADC RIGHT' came on. The FO (First Officer) was flying the aircraft. I pulled up the electronic checklist and read aloud the condition and objective and the first three items of the checklist which are to turn off the autopilot; ATS; and Flight Directors. At this point the FO and I discussed duties briefly (i.e.; FO Fly while Captain runs the checklist). When the FO felt comfortable; we turned everything off and the FO was hand flying just off of raw data. The checklist then ask if the EICAS MSG: is ADC Center MSG shown; I answered no; then the next step in the checklist is 'CENTER AIR DATA SELECTOR... ON R'. I looked all over the Instrument panel for Center Air data selector; could not find it. This is where I regressed to older aircraft I have flown and thought 'Center Air Data was the same as 'Central Air Data Computer' (CADC) and flying mostly the -400 I was also thinking we had only 2 ADC's when in fact we had 3 (747-8). So I took control of the aircraft and told the FO to position his ADC Source selector to Right. This is where things really got bad. By putting the FO's source selector to right I in fact took away his PFD. I handed control back to the FO as I continued to run the checklist. It was at this time the FO sounded off loudly and clearly the 'He had nothing 'on his side. I was trying to get through the checklist and did not look at his PFD. I basically shut him down (thinking he still had raw data on his side) and told him to let me finish the checklist. The FO at this time is flying cross cockpit off of raw data on the Captains instruments that were working satisfactorily. Finally after several overrides on the checklist we came to FO ADC Source selector... L; the FO accomplished this and the FO's PFD was restored. At no time did we deviate from assigned altitude or routing. We re-automated and advised ATC we were unable RVSM; ATC issued 15 degree left turn and a minute later instructed a descent to 28000 ft.; after the descent we finished the remainder of the flight uneventfully.The crew makeup was two Captains and one FO. Since data was good on my side I should have been the one flying the aircraft. The other Captain was present trying to help out with the hard copy checklist. He gave valuable inputs but I was running the show. The smart thing to have done would have been to let the other Captain and the FO run the checklist while I fly since there were no faults on my side. Putting that aside; when the FO was trying to tell me he had nothing on his side and had I stopped and analyzed our situation; maybe I would have taken over flying duties and allowed this very capable FO to run the checklist. I regretfully did not. The other thing is the Center Air Data switch is on the overhead panel. It wasn't until after landing the other Captain realized this and told me. It would have been helpful if the checklist read CENTER AIR DATA selector (on overhead panel) R. Since this switch is never or rarely talked about or trained on.
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.