AD 2006-13-17 ACTIVE

The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 757-200 series airplanes. This AD requires a one- time deactivation of the auxiliary fuel system, repetitive venting and draining of the auxiliary fuel tank sumps, and revising the Limitations section of the airplane flight manual to limit the maximum cargo weight. This AD results from a re-evaluation of the floor structure and cargo barriers conducted by the STC holder. We are issuing this AD to prevent structural overload of the auxiliary fuel tank support structure, which could cause the floor beams to fail, damaging the primary flight controls and the auxiliary power unit fuel lines that pass through the floor beams, resulting in loss of control of the airplane. We are also issuing this AD to prevent structural overload of the cargo barriers, which could cause the barriers to fail, allowing the cargo to shift, resulting in damage to the auxiliary fuel tanks, residual fuel leakage, and consequent increased risk of a fire.

Final rule; request for comments.

2006-13-17 Boeing: Amendment 39-14670. Docket No. FAA-2006-25175; Directorate Identifier 2006-NM-099-AD. \n\nEffective Date \n\n\t(a) This AD becomes effective July 13, 2006. \n\nAffected ADs \n\n\t(b) None. \n\nApplicability \n\n\t(c) This AD applies to Boeing Model 757-200 series airplanes, certificated in any category; modified by Supplemental Type Certificate (STC) SA979NE, having serial numbers identified in PATS Aircraft Service Bulletin SA979NE-28-SB-28--IR, dated April 3, 2006. \n\nUnsafe Condition \n\n\t(d) This AD results from a re-evaluation of the floor structure and cargo barriers conducted by the STC holder. We are issuing this AD to prevent structural overload of the auxiliary fuel tank support structure, which could cause the floor beams to fail, damaging the primary flight controls and the auxiliary power unit fuel lines that pass through the floor beams, resulting in loss of control of the airplane. We are also issuing this AD to prevent structural overload of the cargobarriers, which could cause the barriers to fail, allowing the cargo to shift, resulting in damage to the auxiliary fuel tanks, residual fuel leakage, and consequent increased risk of a fire. \n\nCompliance \n\n\t(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. \n\nService Bulletin References \n\n\t(f) The term "service bulletin,'' as used in this AD, means the Accomplishment Instructions and Maintenance Requirements of PATS Aircraft Service Bulletin SA979NE-28-SB-28-IR, dated April 3, 2006. \n\nDeactivation of the Auxiliary Fuel System and Revised Cargo Weight Limits \n\n\t(g) Within 30 days after the effective date of this AD: Do the actions in paragraphs (g)(1) and (g)(2) of this AD. Thereafter, do the actions in paragraphs (h) and (i) of this AD at the times specified in those paragraphs. \n\n\t(1) Deactivate the auxiliary fuel system by doing all of the actions specified in Part III and all of the actions for the applicable airplane configuration specified in Part IV of the service bulletin. \n\n\t(2) Revise the Limitations section of the Boeing 757-200 Airplane Flight Manual (AFM) to include revised maximum cargo weight limits specified in the applicable AFM supplement identified in Table 1 of this AD. Operate the airplane according to the limitations in the AFM supplements. \n\n\tTable 1.--Applicable AFM Supplements for Revised Cargo Weight Limits \n\n\n\nFor airplanes having S/Ns- \nUse PATS Aircraft AFM supple-ment- \n29025, 29026, 29027, and 29028 (STC Configuration F, which has been upgraded to Configuration H) \n142, dated May 31, 2006. \n24923 (STC Configuration A) \n143, dated May 31, 2006. \n25155 and 25220 (STC Configuration C & D) \n144, dated May 31, 2006. \n28463 (STC Configuration E) \n145, dated May 31, 2006. \n22690 and 25487 (STC Configuration B & G) \n146, dated May 31, 2006. \n\nRepetitive Venting of the Built-Up Pressure in the AuxiliaryFuel Tanks \n\n\t(h) After deactivating the auxiliary fuel system as specified in paragraph (g) of this AD: Following each flight, vent the auxiliary fuel tanks by doing all of the actions specified in paragraph A. of Part V of the service bulletin. \n\nRepetitive Draining of the Fuel Tank Sumps for Residual Fuel \n\n\t(i) At intervals not to exceed 100 flight cycles following deactivation of the auxiliary fuel system, as specified in paragraph (g) of this AD: Drain the auxiliary fuel tank sumps to remove any built-up residual fuel by doing all of the actions specified in paragraph B. of Part V of the service bulletin. \n\nSpecial Flight Permits \n\n\t(j) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the airplane can be modified, provided the airplane is operated with the auxiliary fuel tanks empty. \n\nAlternative Methods of Compliance (AMOCs)(k)(1) The Manager, New York Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19. \n\n\t(2) Before using any AMOC approved in accordance with Sec. 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office. \n\nMaterial Incorporated by Reference \n\n\t(l) You must use PATS Aircraft Service Bulletin SA979NE-28-SB- 28--IR, dated April 3, 2006, and the applicable PATS Aircraft supplement to the Boeing 757-200 Airplane Flight Manual identified in Table 2 of this AD, as applicable, to perform the actions that are required by this AD, unless the AD specifies otherwise. \n\n\tTable 2.--Airplane Flight Manual Supplements for Incorporation by Reference \n\n\nPATS Aircraft airplane flight manual supplement- \nDated- \n142 ............................ \nMay 31, 2006. \n143 ............................ \nMay 31, 2006. \n144 ............................ \nMay 31, 2006. \n145 ............................ \nMay 31, 2006. \n146 ............................ \nMay 31, 2006. \n\n\tThe Director of the Federal Register approved the incorporation by reference of these documents in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact PATS Aircraft, LLC, Product Support, 21652 Nanticoke Avenue, Georgetown, DE 19947, for a copy of this service information. You may review copies at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street, SW., Room PL-401, Nassif Building, Washington, DC; on the Internet at http://dms.dot.gov; or at the National Archives and Records Administration (NARA). For information on the availability of this material at the NARA, call (202) 741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html .

Discussion \n\n\tPATS Aircraft (holder of Supplemental Type Certificate (STC) SA979NE) notified us that it has determined that Model 757-200 series airplanes equipped with auxiliary fuel tank systems installed by STC SA979NE have insufficient structural strength in the auxiliary fuel tank support structure. The STC holder has also determined that the cargo barriers have insufficient structural strength if subjected to emergency landing loads with more than 2,000 pounds of cargo in the cargo compartment. These determinations were based on a new structural analysis resulting from a re-evaluation of the floor structure and cargo barriers conducted by the STC holder. Structural overload of the auxiliary fuel tank support structure could cause the floor beams to fail, damaging the primary flight controls and the auxiliary power unit fuel lines that pass through the floor beams; this condition, if not corrected, could result in loss of control of the airplane. Structural overload of the cargo barriers could cause the barriers to fail, allowing the cargo to shift; this condition, if not corrected, could result in damage to the auxiliary fuel tanks, residual fuel leakage, and consequent increased risk of a fire. \n\nRelevant Service Information \n\n\tWe have reviewed PATS Aircraft Service Bulletin SA979NE-28-SB-28-- IR, dated April 3, 2006. The service bulletin describes procedures for deactivating the auxiliary fuel system, and installing new cargo loading weight limits and "INOP'' placards, depending on the airplane configuration. The service bulletin also describes procedures for venting any residual air pressure from the auxiliary fuel tanks following each flight and draining the auxiliary fuel tank sumps to regularly remove any residual fuel that may accumulate over time due to leakage around the auxiliary fuel tank valves. Paragraph I.D. ("Description'') of the service bulletin describes limiting the maximum cargo weight to 2,000 pounds (as specified on the new cargo weight placards) in the forward and aft cargo compartments, as applicable, depending on the STC configuration of the airplane. \n\n\tWe have also reviewed the PATS Aircraft supplements to the Limitations section of the Boeing 757-200 Airplane Flight Manual (AFM), which are identified in the following table. These AFM supplements provide revised maximum cargo weight limits. \n\n\tTable.--Applicable AFM Supplements for Revised Cargo Weight Limits \n\n\n\nFor airplanes having S/Ns- \nUse PATS Aircraft AFM supple-ment- \n29025, 29026, 29027, and 29028 (STC Configuration F, which has been upgraded to Configuration H) \n142, dated May 31, 2006. \n24923 (STC Configuration A) \n143, dated May 31, 2006. \n25155 and 25220 (STC Configuration C & D) \n144, dated May 31, 2006. \n28463 (STC Configuration E) \n145, dated May 31, 2006. \n22690 and 25487 (STC Configuration B & G) \n146, dated May 31, 2006. \n\nFAA's Determination and Requirements of This AD \n\n\tThe unsafe conditions described previously are likely to exist or develop on other airplanes of the same type design. We are issuing this AD to prevent structural overload of the auxiliary fuel tank support structure, which could cause the floor beams to fail, damaging the primary flight controls and the auxiliary power unit fuel lines that pass through the floor beams, resulting in loss of control of the airplane. We are also issuing this AD to prevent structural overload of the cargo barriers, which could cause the barriers to fail, allowing the cargo to shift, resulting in damage to the auxiliary fuel tanks, residual fuel leakage, and consequent increased risk of a fire. This AD requires accomplishing the actions specified in the service information described previously, except as discussed under "Differences Between the AD and the Service Bulletin.'' \n\nDifferences Between the AD and the Service Bulletin \n\n\tPATS Aircraft Service Bulletin SA979NE-28-SB-28--IR, dated April 3, 2006, does not specify a compliance time for deactivating the auxiliary fuel system or implementing the new cargo weight limits. In developing an appropriate compliance time for those actions in this AD, we considered the degree of urgency associated with the subject unsafe condition, the average utilization of the affected fleet, and the time necessary to perform the deactivation (3 hours) and AFM revision. In light of all of these factors, we find that a 30-day compliance time represents an appropriate interval of time for affected airplanes to continue to operate without compromising safety. \n\nInterim Action \n\n\tWe consider this AD interim action. The STC holder is currently developing a modification that will address the unsafe conditions identified in this AD. Once this modification is developed, approved, and available, we may consider additional rulemaking. \n\nFAA's Determination of the Effective Date \n\n\tSince unsafe conditions exists that require the immediate adoption of this AD, we havefound that notice and opportunity for public comment before issuing this AD are impracticable, and that good cause exists to make this AD effective in less than 30 days. \n\nComments Invited \n\n\tThis AD is a final rule that involves requirements that affect flight safety and was not preceded by notice and an opportunity for public comment; however, we invite you to submit any relevant written data, views, or arguments regarding this AD. Send your comments to an address listed in the ADDRESSES section. Include "Docket No. FAA-2006- 25175; Directorate Identifier 2006-NM-099-AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the AD that might suggest a need to modify it. \n\n\tWe will post all comments we receive, without change, to http://dms.dot.gov , including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this AD. Using the search function of that Web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you may visit http://dms.dot.gov. \n\nExamining the Docket \n\n\tYou may examine the AD docket on the Internet at http://dms.dot.gov , or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647- 5227) is located on the plaza level of the Nassif Building at the DOT street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after the Docket Management System receives them. \n\nAuthority for This Rulemaking \n\n\tTitle 49 of the United StatesCode specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority. \n\n\tWe are issuing this rulemaking under the authority described in subtitle VII, part A, subpart III, section 44701, "General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses unsafe conditions that are likely to exist or develop on products identified in this rulemaking action. \n\nRegulatory Findings \n\n\tWe have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the National government and the States, or on the distribution of power and responsibilities among the various levels of government. \n\n\tFor the reasons discussed above, I certify that the regulation: \n\n\t1. Is not a "significant regulatory action'' under Executive Order 12866; \n\n\t2. Is not a "significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and \n\n\t3. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. \n\n\tWe prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation. \n\nList of Subjects in 14 CFR Part 39 \n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment \n\nAccordingly, under the authority delegated tome by the Administrator, the FAA amends 14 CFR part 39 as follows: \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n1. The authority citation for part 39 continues to read as follows: \n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\nSec. 39.13 (Amended) \n\n2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by adding the following new airworthiness directive (AD):

Use one of the following addresses to submit comments on this AD.\n \n\tDOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically. \n\n\tGovernment-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.\n \n\tMail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 20590. \n\n\tFax: (202) 493-2251. \n\n\tHand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. \n\n\tContact PATS Aircraft, LLC, Product Support, 21652 Nanticoke Avenue, Georgetown, DE 19947, for service information identified in this AD.

Jon Hjelm, Aerospace Engineer, Airframe and Propulsion Branch, ANE-171, FAA, New York Aircraft Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590; telephone (516) 228-7323; fax (516) 794-5531.