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|
Attributes | |
ACN | 1576121 |
Time | |
Date | 201809 |
Place | |
Locale Reference | ZZZ.Airport |
State Reference | US |
Aircraft 1 | |
Make Model Name | B757 Undifferentiated or Other Model |
Operating Under FAR Part | Part 121 |
Flight Phase | Parked |
Component | |
Aircraft Component | Pitot-Static System |
Person 1 | |
Function | Other / Unknown |
Qualification | Maintenance Powerplant Maintenance Airframe |
Events | |
Anomaly | Deviation - Procedural FAR Deviation - Procedural Published Material / Policy |
Narrative:
Aircraft was undergoing C check work. Part of the work accomplished was to replace all 4 pitot probes; captain-first officer-auxiliary 1 and auxiliary 2. There is confusion on what procedure to follow regarding flight requirements after all 4 pitot probes are replaced. During the check; they followed [the] card which directs maintenance to replace all 4 probes. Nowhere in that document is it stated any 'operational confirmation' or 'test flight' is required after the work is performed. The probes are being replaced to improve overall reliability and zero time the probes.an [engineering document] was initially written. In this [document] under step 9 it specifically states: if 3 or more pitot probes were replaced as part of this maintenance visit (combination of operations 1; 2; 3; or 4); then a flight test is required. When accomplishing at a [maintenance base] location; coordinate with the on-site representatives to schedule the flight test. When accomplishing at all other stations; coordinate with maintenance control to schedule the flight test.the language they use is flight test. Based on this information; one could construe that the requirement is a test flight after all 4 probes are replaced. It is only option #1 of 4 but all [options] state the same information under item #9.gmm (general maintenance manual) clearly breaks down what an operational confirmation flight and test flight is and what type of crews can fly them. A test flight requires an engineering test crew (aka-flight standards) to accomplish the flight. This is essentially what the [engineering document] is stating; however; there is nothing in the jic that states either of them. An operational confirmation flight can be flown by either a 'line crew' or engineering test crew as this type of flight is not anticipating the use of 'non-normal' procedures. Where an engineering test crew flying a test flight will use non-normal procedures amongst other 'test' procedures to assure aircraft operation is within allowable tolerances.this is critical in the sense of safety what flight and crew type is flying the aircraft and what procedures and systems are being tested. In addition; the gmm has no information regarding pitot probe replacement and the requirement for a specific flight type; unlike other work that can drive a test flight. Being that the [engineering document] specifically identified flight test in the procedure; the assumption would be that since all 4 probes were replaced; that there is a high potential for system inaccuracies during the first flight after maintenance and engineering believes the safest procedure to use is to utilize the engineering test crew under a test flight scenario.so; the primary issue is that the jic does not require any type test/operational flight where the [engineering document] does. Also; nowhere in the jic does it fall back or ref the ea to review its requirements. Thus; there were multiple emails sent out looking for information on the procedure to use; etc. At the end of my shift; I made a log item to accomplish a test flight with an engineering test crew which falls under group ii per the gmm. After my departure; senior leadership sent out multiple emails which further muddied the waters by stating group ii and then group I test flight. There is no such thing as 'group I test flight'; a test flight is always a group ii. An operational confirmation flight is a 'group I' as it can be flown by a line crew using normal procedures.we are asking for trouble when senior leadership gives edicts on procedures that essentially contradict what an engineering document calls for especially when part of email string identifies the [engineering document] to reference for the direction [maintenance control] provides. In the end; my log page was deleted and a new log was generated to accomplish a 'group I test flight' by another controller. [This is] incorrect nomenclature. The jic needs to be updated after review of the [engineering document] to determine what requirements are to be accomplished before we find ourselves in a situation that may cause an accident or incident. The primary issue is the jic and [engineering document] contradiction.
Original NASA ASRS Text
Title: B757 Maintenance Controller reported that the maintenance procedures were ambiguous whether to require a test or confirmation flight.
Narrative: Aircraft was undergoing C Check work. Part of the work accomplished was to replace all 4 pitot probes; Captain-First Officer-Auxiliary 1 and Auxiliary 2. There is confusion on what procedure to follow regarding flight requirements after all 4 pitot probes are replaced. During the check; they followed [the] card which directs Maintenance to replace all 4 probes. Nowhere in that document is it stated any 'Operational Confirmation' or 'Test Flight' is required after the work is performed. The probes are being replaced to improve overall reliability and zero time the probes.An [Engineering document] was initially written. In this [document] under step 9 it specifically states: If 3 or more pitot probes were replaced as part of this maintenance visit (combination of Operations 1; 2; 3; or 4); then a flight test is required. When accomplishing at a [maintenance base] location; coordinate with the On-Site representatives to schedule the flight test. When accomplishing at all other stations; coordinate with Maintenance Control to schedule the flight test.The language they use is Flight Test. Based on this information; one could construe that the requirement is a Test Flight after all 4 probes are replaced. It is only Option #1 of 4 but all [options] state the same information under item #9.GMM (General Maintenance Manual) clearly breaks down what an Operational Confirmation Flight and Test Flight is and what type of crews can fly them. A Test flight requires an Engineering Test Crew (AKA-Flight Standards) to accomplish the flight. This is essentially what the [Engineering document] is stating; however; there is nothing in the JIC that states either of them. An Operational Confirmation flight can be flown by either a 'Line Crew' or Engineering Test Crew as this type of flight is not anticipating the use of 'NON-NORMAL' procedures. Where an Engineering Test Crew flying a test flight will use non-normal procedures amongst other 'test' procedures to assure aircraft operation is within allowable tolerances.This is critical in the sense of safety what flight and crew type is flying the aircraft and what procedures and systems are being tested. In addition; the GMM has no information regarding Pitot Probe replacement and the requirement for a specific flight type; unlike other work that can drive a Test Flight. Being that the [Engineering document] specifically identified Flight Test in the procedure; the assumption would be that since all 4 probes were replaced; that there is a high potential for system inaccuracies during the first flight after Maintenance and Engineering believes the safest procedure to use is to utilize the Engineering Test Crew under a TEST FLIGHT scenario.So; the primary issue is that the JIC does not require any type test/operational flight where the [Engineering document] does. Also; nowhere in the JIC does it fall back or ref the EA to review its requirements. Thus; there were multiple emails sent out looking for information on the procedure to use; etc. At the end of my shift; I made a log item to accomplish a Test Flight with an Engineering Test Crew which falls under Group II per the GMM. After my departure; senior leadership sent out multiple emails which further muddied the waters by stating Group II and then Group I test flight. There is no such thing as 'GROUP I Test Flight'; a test flight is always a Group II. An operational confirmation flight is a 'GROUP I' as it can be flown by a line crew using normal procedures.We are asking for trouble when Senior Leadership gives EDICTS on procedures that essentially contradict what an engineering document calls for especially when part of email string identifies the [Engineering document] to reference for the direction [Maintenance Control] provides. In the end; my log page was deleted and a new log was generated to accomplish a 'GROUP I Test Flight' by another controller. [This is] incorrect nomenclature. The JIC needs to be updated after review of the [Engineering document] to determine what requirements are to be accomplished before we find ourselves in a situation that may cause an accident or incident. The primary issue is the JIC and [Engineering document] contradiction.
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.