[Federal Register Volume 71, Number 192 (Wednesday, October 4, 2006)]
[Rules and Regulations]
[Pages 58493-58495]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-16199]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-24256; Directorate Identifier 2006-NM-010-AD; 
Amendment 39-14782; AD 2006-20-12]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model 717-200 
Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain McDonnell Douglas Model 717-200 airplanes. This AD requires 
replacing the lightning critical clamp bases of the fuel tank vent 
system with improved clamp bases; and checking the electrical bond of 
the modified self-bonding mounting clamps and corrective action if 
necessary. This AD results from an investigation that revealed the 
aluminum foil strip on the nylon base of the ground clamps can fracture 
or separate from the base. We are issuing this AD to ensure that the 
fuel pipes are properly bonded to the airplane structure. Improper 
bonding could prevent electrical energy from a lightning strike from 
dissipating to the airplane structure, which could result in a fuel 
tank explosion.

DATES: This AD becomes effective November 8, 2006.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of November 8, 
2006.

ADDRESSES: You may examine the AD docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility, U.S. 
Department of Transportation, 400 Seventh Street SW., Nassif Building, 
Room PL-401, Washington, DC.
    Contact Boeing Commercial Airplanes, Long Beach Division, 3855 
Lakewood Boulevard, Long Beach, California 90846, Attention: Data and 
Service Management, Dept. C1-L5A (D800-0024), for service information 
identified in this AD.

FOR FURTHER INFORMATION CONTACT: Serj Harutunian, Aerospace Engineer, 
Propulsion Branch, ANM-140L, FAA, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; 
telephone (562) 627-5254; fax (562) 627-5210.

SUPPLEMENTARY INFORMATION:

Examining the Docket

    You may examine the airworthiness directive (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 street address stated in the ADDRESSES section.

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to include an AD that would apply to certain McDonnell 
Douglas Model 717-200 airplanes. That NPRM was published in the Federal 
Register on March 28, 2006 (71 FR 15351). That NPRM proposed to require 
replacing the lightning critical clamp bases of the fuel tank vent 
system with improved clamp bases; and checking the electrical bond of 
the modified self-bonding mounting clamps.

Actions Since NPRM Was Issued

    Since we issued the NPRM, Boeing has released Service Bulletin 717-
28-0004, Revision 3, dated June 21, 2006. In the NPRM, we referenced 
Revision 2 of the service bulletin, dated March 11, 2005, as the 
appropriate source of service information. The procedures in Revision 3 
are essentially the same as those in Revision 2. Revision 3 also 
provides detailed instructions for checking the electrical bond of the 
modified self-bonding mounting clamps and accomplishing corrective 
actions if necessary. If the electrical conductivity of the surface is 
greater than 2.5 milliohms, the corrective actions include surface 
prepping and applying a chemical conversion coat to the surface of the 
structural bracket and vent pipe. (The NPRM proposed to repair the 
electrical bond of the mounting clamp according to a method approved by 
the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, if 
any electrical bond fails the check. The NPRM specified that Chapter 
28-00-00 of the Boeing 717 Aircraft Maintenance Manual and Chapter 20-
50-01 of the Boeing 717 Standard Wiring Practices Manual (SWPM) are one 
approved method.)
    We have revised paragraph (f) of this AD to reference Revision 3 as 
the appropriate source of service information for replacing the 
lightning critical clamp bases of the fuel tank vent system with 
improved clamp bases; and checking the electrical bond of the modified 
self-bonding mounting clamps. We have also revised paragraph (f) to 
allow operators to either repair any electrical bond in accordance with 
Revision 3 of the service bulletin, or according to a method approved 
by the Manager, Los Angeles ACO. In addition, we have added a new 
paragraph (g) to this AD, giving credit for actions done before the 
effective date of this AD in accordance with Revision 2. We have also 
revised the applicability of paragraph (c) of this AD to reference 
Revision 3. Revision 2 and Revision 3 both apply to Model 717-200 
airplanes having fuselage numbers 5002 through 5121 inclusive; 
therefore, the applicability of this AD has not changed.

[[Page 58494]]

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comment received.

Support for the NPRM

    Boeing and AirTran Airways support the NPRM.

Request for Clarification

    AirTran Airways states that Boeing Service Bulletin 717-28-0004 
refers to Chapter 20-50-01 of the Boeing DC, MD, and 717 SWPM, Class 
``L,'' for instructions on accomplishing a check of the electrical 
bonds. AirTran Airways points out that Class ``L'' is not identified in 
Chapter 20-50-01 of the SWPM; instead, that chapter provides the 
maximum direct current (DC) resistance and path for lightning 
protection. Therefore, AirTran requests clarification of Class ``L.''
    As stated previously, since the NPRM was issued, Boeing has issued 
Revision 3 of the service bulletin and that revision is cited in this 
final rule. Revision 3 deletes the reference to Class ``L.''

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

    There are about 120 airplanes of the affected design in the 
worldwide fleet. This AD affects about 92 airplanes of U.S. registry. 
The required actions take about 16 work hours per airplane, at an 
average labor rate of $80 per work hour. Required parts cost about $239 
per airplane. Based on these figures, the estimated cost of the AD for 
U.S. operators is $139,748, or $1,519 per airplane.

Authority for This Rulemaking

    Title 49 of the United States Code 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.
    We 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 an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We 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.
    For the reasons discussed above, I certify that this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866;
    (2) Is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and
    (3) 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.
    We 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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec.  39.13  [Amended]

0
2. The Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

2006-20-12 McDonnell Douglas: Amendment 39-14782. Docket No. FAA-
2006-24256; Directorate Identifier 2006-NM-010-AD.

Effective Date

    (a) This AD becomes effective November 8, 2006.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to McDonnell Douglas Model 717-200 
airplanes, certificated in any category; as identified in Boeing 
Service Bulletin 717-28-0004, Revision 3, dated June 21, 2006.

Unsafe Condition

    (d) This AD results from an investigation that revealed the 
aluminum foil strip on the nylon base of the ground clamps can 
fracture or separate from the base. We are issuing this AD to ensure 
that the fuel pipes are properly bonded to the airplane structure. 
Improper bonding could prevent electrical energy from a lightning 
strike from dissipating to the airplane structure, which could 
result in a fuel tank explosion.

Compliance

    (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.

Replace the Grounded Clamp Bases

    (f) Within 78 months after the effective date of this AD, 
replace the lightning critical clamp bases of the fuel tank vent 
system with improved clamp bases, in accordance with Table 1 of 
Figure 1 of the Accomplishment Instructions of Boeing Service 
Bulletin 717-28-0004, Revision 3, dated June 21, 2006. Before 
further flight after the replacement, check the electrical bond of 
the modified self-bonding mounting clamps in accordance with the 
Accomplishment Instructions of the service bulletin. If any 
electrical bond fails the check, before further flight, repair the 
electrical bond of the mounting clamp in accordance with the service 
bulletin; or according to a method approved by the Manager, Los 
Angeles Aircraft Certification Office (ACO), FAA. Chapter 28-00-00 
of the Boeing 717 Aircraft Maintenance Manual and Chapter 20-50-01 
of the Boeing DC, MD, and 717 Standard Wiring Practices Manual are 
one approved method.

Credit for Previous Service Bulletin

    (g) Actions done before the effective date of this AD in 
accordance with Boeing Service Bulletin 717-28-0004, Revision 2, 
dated March 11, 2005, are acceptable for compliance with the 
requirements of paragraph (f) of this AD.

Alternative Methods of Compliance (AMOCs)

    (h)(1) The Manager, Los Angeles ACO, FAA, has the authority to 
approve AMOCs for this AD, if requested in accordance with the 
procedures found in 14 CFR 39.19.
    (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.

Material Incorporated by Reference

    (i) You must use Boeing Service Bulletin 717-28-0004, Revision 
3, dated June 21, 2006, to perform the actions that are required

[[Page 58495]]

by this AD, unless the AD specifies otherwise. The Director of the 
Federal Register approved the incorporation by reference of this 
document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. 
Contact Boeing Commercial Airplanes, Long Beach Division, 3855 
Lakewood Boulevard, Long Beach, California 90846, Attention: Data 
and Service Management, Dept. C1-L5A (D800-0024), 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.

    Issued in Renton, Washington, on September 25, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E6-16199 Filed 10-3-06; 8:45 am]
BILLING CODE 4910-13-P