Narrative:

On feb/xa/98 at XA25 I participated as the flight engineer on a B727- 100. As previously described in my initial NASA report submitted dec 97, I preflted the aircraft as required by flight engineer preflight checklist in the air carrier's B727 flight handbook. I observed that the standby attitude indicator 'power interruption warning flag' came into view while simulating the loss of all generator power. Per far 121.305(K)(4) and the differences section of the air carrier's training and reference manual (which clearly states that the standby attitude indicator on this particular aircraft is in compliance with the above referenced far), it was clearly obvious that this aircraft is in violation with the far 121.305(K)(4). As a result of the same concerns which precipitated my initial NASA report of an incident on dec/xa/97, and follow-up contact with mr Z of the indianapolis FSDO. Mr Z told me on feb/xb/98 that this standby attitude indicator confign had been determined by the air carrier's pmi, not to be in compliance with the far 121.305(K)(4), and that there was no authority/authorized for it to be configured in violation of far 121.305(K)(4). The avionics technician, to whom I directed my questions, said that he knew nothing of any recent changes and/or decisions that countermanded the previous decision by the pmi that these standby attitude indicator configns were authority/authorized. Considering that I not yet had had the opportunity to confirm the correct status of this standby attitude indicator confign with maintenance, and knowing that refusing to participate on this flight as the flight engineer would have resulted in my dismissal from employment, I departed as scheduled. To date, I am still not clear whether or not the sai configuration on this aircraft is legal. I do know that this is unsafe because a complete loss of aircraft generators could very well result in the loss of all attitude and bank references, the very condition justifying the requirement of far 121.305 (K)(4). In night and/or IMC conditions this situation can easily be disastrous. I have still yet to receive any documentation that this sai configuration is legal. Further, I am requesting that your office request the FAA to initiate an investigation into this matter since this condition still exists and continues to create the potential for an in-flight disaster. Callback conversation with reporter revealed the following information: the reporter said that he is checking each of his company's B727-100's and that in all of the ones that have been modified where the dc pwred standby attitude indicators have been replaced with AC pwred units the modifications are in violation of far part 121.305(K)(4). This far requires the power to the standby instruments to be automatically connected if the main electrical supply should fail. The reporter said that in properly modified aircraft the standby AC pwred instruments are pwred by a separate inverter connected to the switched battery bus. On the improperly modified aircraft the standby instruments are pwred by the standby inverter and the inverter is not pwred when the main electrical power fails until the essential power switch is rotated to a pwred source (the battery). On this company's mixed fleet the pwred selection is labeled either 'standby power' or 'emergency power.' on the properly equipped aircraft the standby instruments are still pwred, without switching, when the main electrical power fails. The far is clear regarding this unswitched requirement according to the reporter.

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Original NASA ASRS Text

Title: AN ACR FREIGHTER FLC ON A B727 DISCOVERED THAT ON THEIR RECENTLY MODIFIED ACFT, THE STANDBY INSTS WILL NO LONGER BE PWRED WHEN THE MAIN ELECTRICAL PWR FAILS UNLESS THEY SELECT A PWRED SOURCE THROUGH THE ESSENTIAL PWR SELECTOR. THIS APPEARS TO BE IN VIOLATION OF THE REQUIREMENTS OF FAR PART 121 PT 305(K)(4).

Narrative: ON FEB/XA/98 AT XA25 I PARTICIPATED AS THE FE ON A B727- 100. AS PREVIOUSLY DESCRIBED IN MY INITIAL NASA RPT SUBMITTED DEC 97, I PREFLTED THE ACFT AS REQUIRED BY FE PREFLT CHKLIST IN THE ACR'S B727 FLT HANDBOOK. I OBSERVED THAT THE STANDBY ATTITUDE INDICATOR 'PWR INTERRUPTION WARNING FLAG' CAME INTO VIEW WHILE SIMULATING THE LOSS OF ALL GENERATOR PWR. PER FAR 121.305(K)(4) AND THE DIFFERENCES SECTION OF THE ACR'S TRAINING AND REF MANUAL (WHICH CLRLY STATES THAT THE STANDBY ATTITUDE INDICATOR ON THIS PARTICULAR ACFT IS IN COMPLIANCE WITH THE ABOVE REFED FAR), IT WAS CLRLY OBVIOUS THAT THIS ACFT IS IN VIOLATION WITH THE FAR 121.305(K)(4). AS A RESULT OF THE SAME CONCERNS WHICH PRECIPITATED MY INITIAL NASA RPT OF AN INCIDENT ON DEC/XA/97, AND FOLLOW-UP CONTACT WITH MR Z OF THE INDIANAPOLIS FSDO. MR Z TOLD ME ON FEB/XB/98 THAT THIS STANDBY ATTITUDE INDICATOR CONFIGN HAD BEEN DETERMINED BY THE ACR'S PMI, NOT TO BE IN COMPLIANCE WITH THE FAR 121.305(K)(4), AND THAT THERE WAS NO AUTH FOR IT TO BE CONFIGURED IN VIOLATION OF FAR 121.305(K)(4). THE AVIONICS TECHNICIAN, TO WHOM I DIRECTED MY QUESTIONS, SAID THAT HE KNEW NOTHING OF ANY RECENT CHANGES AND/OR DECISIONS THAT COUNTERMANDED THE PREVIOUS DECISION BY THE PMI THAT THESE STANDBY ATTITUDE INDICATOR CONFIGNS WERE AUTH. CONSIDERING THAT I NOT YET HAD HAD THE OPPORTUNITY TO CONFIRM THE CORRECT STATUS OF THIS STANDBY ATTITUDE INDICATOR CONFIGN WITH MAINT, AND KNOWING THAT REFUSING TO PARTICIPATE ON THIS FLT AS THE FE WOULD HAVE RESULTED IN MY DISMISSAL FROM EMPLOYMENT, I DEPARTED AS SCHEDULED. TO DATE, I AM STILL NOT CLEAR WHETHER OR NOT THE SAI CONFIGURATION ON THIS AIRCRAFT IS LEGAL. I DO KNOW THAT THIS IS UNSAFE BECAUSE A COMPLETE LOSS OF ACFT GENERATORS COULD VERY WELL RESULT IN THE LOSS OF ALL ATTITUDE AND BANK REFERENCES, THE VERY CONDITION JUSTIFYING THE REQUIREMENT OF FAR 121.305 (K)(4). IN NIGHT AND/OR IMC CONDITIONS THIS SIT CAN EASILY BE DISASTROUS. I HAVE STILL YET TO RECEIVE ANY DOCUMENTATION THAT THIS SAI CONFIGURATION IS LEGAL. FURTHER, I AM REQUESTING THAT YOUR OFFICE REQUEST THE FAA TO INITIATE AN INVESTIGATION INTO THIS MATTER SINCE THIS CONDITION STILL EXISTS AND CONTINUES TO CREATE THE POTENTIAL FOR AN INFLT DISASTER. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR SAID THAT HE IS CHKING EACH OF HIS COMPANY'S B727-100'S AND THAT IN ALL OF THE ONES THAT HAVE BEEN MODIFIED WHERE THE DC PWRED STANDBY ATTITUDE INDICATORS HAVE BEEN REPLACED WITH AC PWRED UNITS THE MODIFICATIONS ARE IN VIOLATION OF FAR PART 121.305(K)(4). THIS FAR REQUIRES THE PWR TO THE STANDBY INSTS TO BE AUTOMATICALLY CONNECTED IF THE MAIN ELECTRICAL SUPPLY SHOULD FAIL. THE RPTR SAID THAT IN PROPERLY MODIFIED ACFT THE STANDBY AC PWRED INSTS ARE PWRED BY A SEPARATE INVERTER CONNECTED TO THE SWITCHED BATTERY BUS. ON THE IMPROPERLY MODIFIED ACFT THE STANDBY INSTS ARE PWRED BY THE STANDBY INVERTER AND THE INVERTER IS NOT PWRED WHEN THE MAIN ELECTRICAL PWR FAILS UNTIL THE ESSENTIAL PWR SWITCH IS ROTATED TO A PWRED SOURCE (THE BATTERY). ON THIS COMPANY'S MIXED FLEET THE PWRED SELECTION IS LABELED EITHER 'STANDBY PWR' OR 'EMER PWR.' ON THE PROPERLY EQUIPPED ACFT THE STANDBY INSTS ARE STILL PWRED, WITHOUT SWITCHING, WHEN THE MAIN ELECTRICAL PWR FAILS. THE FAR IS CLR REGARDING THIS UNSWITCHED REQUIREMENT ACCORDING TO THE RPTR.

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.