From: Boeing Customer Support
Subject: SB 747-53-2460 Rev 2 - Clarification

Date: Monday, June 24, 2013 2:51:23 PM

FROM: THE BOEING COMPANY TO: Delta Air Lines (DAL) [MESSAGE NUMBER:DAL-DAL-13-1299-02B] Boeing Response

MESSAGE DATE: 24 Jun 2013 1251 US PACIFIC TIME / 24 Jun 2013 1951 GMT

The following message is distributed to the following people at Delta Air Lines: Sandy Wiese

Field Service Base: BFSATL

Service Category: Service Bulletin Model: 747 Series/Product: SB - Airplane Service Bulletin

ATA: 5300-00

SUBJECT: SB 747-53-2460 Rev 2 - Clarification

REFERENCES:

/A/ DAL-DAL-13-1299-01F /B/ Boeing Service Bulletin 747-53-2460 Rev 2

DESCRIPTION:

Delta report they are working on an FAA NPRM and have a few questions about the interpretation of a Table in the Boeing Service Bulletin 747-53-2460 Rev 2. Delta would appreciate clarification because they will submit comments through the NPRM process by June 24, that include Boeing's response. Attached is a marked-up section of the service bulletin that relates to the following question in this

email.

1. When DAL reviews Para (r) of NPRM FAA-2013-0366, it is clear and understandable as to the actions and any/all repetitive activities required. When DAL reviews all of the conditions in Table 1 of the SBRev2 that apply to this group "previously inspected Group 4 a/c: corner reveal not replaced or replaced with two piece reveal" =Circle note A and either Circle Note D or E depending on Mat'l ID outcome, we conclude that all of the applicable conditions of Table 1 of the SB align with the proposed AD requirements as defined in Para (r). However, when DAL reviews Para (s) of the NPRM and then reviews the conditions of Table 1 of the SBRev2, DAL questions if either all conditions of Table 1 should

be reviewed/evaluated? DAL believes that only Circle Note C applies (since no material ID is required and therefore determination of casting/ no casting is irrelevant) which leads DAL into Table 8 and the applicable conditions which would align with para (s) AD requirements. Question: How is an operator supposed to know to review/evaluate all remaining conditions Circle note D/E/F of Table 1 for the first condition (circle note A) but in the case of the third Condition (Circle Note C), the operator is expected to ignore the remaining conditions D/E/F. DAL believes a more clear/concise Table could be built to discern the different/unique conditions.

2. Reference sheet 32, Table 8, in the last row under the "Action" column, the highlighted text

shows there is a reference to Table 9. There is not a Table 9 in 747-53-2460 Rev 2. I have also checked Rev 0 and 1 and they do not contain Table 9 either. Could you clarify what is the intended reference for the inspection? (DAL believes "Table 9" notation should be "Paragraph 3.B, PART 2").

RESPONSE AND/OR REQUIRED ACTION :1. When DAL reviews Para (r) of NPRM FAA-2013-0366, it is clear and understandable as to the actions and any/all repetitive activities required. When DAL reviews all of the conditions in Table 1 of the SBRev2 that apply to this group "previously inspected Group 4 a/c: corner reveal not replaced or replaced with two piece reveal" =Circle note A and either Circle Note D or E depending on Mat'l ID outcome, we conclude that all of the applicable conditions of Table 1 of the SB align with the proposed AD requirements as defined in Para (r). However, when DAL reviews Para (s) of the NPRM and then reviews the conditions of Table 1 of the SBRev2, DAL questions if either all conditions of Table 1 should

be reviewed/evaluated? DAL believes that only Circle Note C applies (since no material ID is required and therefore determination of casting/ no casting is irrelevant) which leads DAL into Table 8 and the applicable conditions which would align with para (s) AD requirements. Question: How is an operator supposed to know to review/evaluate all remaining conditions Circle note D/E/F of Table 1 for the first condition (circle note A) but in the case of the third Condition (Circle Note C), the operator is expected to ignore the remaining conditions D/E/F. DAL believes a more clear/concise Table could be built to discern the different/unique conditions.

2. Reference sheet 32, Table 8, in the last row under the "Action" column, the highlighted text

shows there is a reference to Table 9. There is not a Table 9 in 747-53-2460 Rev 2. I have also checked Rev 0 and 1 and they do not contain Table 9 either. Could you clarify what is the intended reference for the inspection? (DAL believes "Table 9" notation should be "Paragraph 3.B, PART 2").

RESPONSE:

In a compliance table, if the action given with a condition includes an inspection, the possible conditions discovered by that inspection are also included in that Compliance table (or possibly another identified compliance table as is the case in Table 1 with the crack inspection). For Compliance Table 1, the conditions labeled D,E,F in the attachment to this SR are conditions established by the material type inspection to determine if the corner reveal is a casting. Condition A is the only condition that includes the material type inspection, so this is what links Conditions D, E, F to Condition A. The conditions labeled C, E and F in the attachment to this SR include an inspection for cracks and the possible conditions associated with the crack inspection are given in Compliance Table 8. With Condition C it is known that the new one-piece reveal is not a casting, so the material type inspection is not necessary. Note that the conditions labeled C and F are equivalent conditions, but Condition F is established by the material type inspection whereas Condition C is linked to a previous change. Regardless of the above explanation, Boeing appreciates this input which suggests that there will be benefit to clarifying the contents of the Compliance table(s). Boeing will take this input into

consideration with the next revision to the SB.

In Table 8 on page 32, the reference to "Table 9" in the Action column should instead be to "Paragraph
3.B., PART 2."

If attachments are referred to, and are not present, please access them by logging into MyBoeingFleet Service Requests application or contact your Boeing Field Service Representative. https://myboeingfleet.boeing.com/servicerequests/index.html?entityId=1- 1549UXP&entityType=CommunicationMessage Suppliers, please access attachments by logging into Boeing Partner Network Supplier Service Requests application.

Michael Schmidt, Structures II - Service Bulletin Engineering - Everett Ron Tropple - Manager