Comments

We provided the public the opportunity to participate in developing this AD. The following presents the comments received on the proposal and FAA's response to each comment:
Comment Issue No. 1: Approve Installing Univair Part Numbers (P/N) UA A815 and UA854 as a Terminating Action for the Repetitive Inspection Requirement for All Affected Taylorcraft Airplanes

Univair Aircraft Corporation (Univair) requests that we expand the airplane model applicability for installation of P/Ns UAA815 and UA 854 as a terminating action for the repetitive inspection requirement from Taylorcraft Models BC12D/D1 and BCS12D/D1 airplanes (as currently approved in an alternative method of compliance (AMOC) to AD 20071614) to include all affected Taylorcraft airplanes.

On January 2, 2008, Univair received parts manufacturer approval (PMA) under PMA Supplement Numbers 198 and 199 expanding the eligibility to install P/Ns UAA815 and UA854 on all Taylorcraft airplane models affected by the proposed AD. Installation of these sealed struts provides an acceptable level of safety for terminating action to the AD for all affected Taylorcraft airplane models.

We agree with the commenter. We will change the final rule AD action to incorporate this change.
Comment Issue No. 2: Extend or Eliminate Repetitive Inspection Intervals

Richard W. Gross and seven other commenters request that the repetitive inspection interval be either extended from 4 years to 10 years or terminated altogether if no corrosion is found during the initial inspection.

Some of the commenters base their request on service history of some struts having been in service for 60 years without any signs of corrosion.

We do not agree with the commenters. We have not received any data to support extending the repetitive inspection interval. We have received reports of several corroded vented wing
[[Page 9656]]
lift struts from different Taylorcraft series airplanes. Repetitive inspections are necessary to detect and correct corrosion that can develop after the initial inspection. Based on the inspection methods used and the application of corrosion inhibitor at each inspection, 48 months is the appropriate repetitive inspection interval.

We are not changing the final rule AD action based on these comments.
Comment Issue No. 3: Remove FModel Airplanes From the Applicability Section

Shawn Coleman and three other commenters request that the newer F Model Taylorcraft airplanes be removed from the Applicability section. This request is based on these models being the most recent airplanes produced and the expectation that they should not have a corrosion problem.

We do not agree with the commenters. We do not have any data to support excluding these airplane models from the AD. These models use the same strut design and material as the earlier produced Taylorcraft model airplanes. We have received reports of one Model F21 airplane and three Model F22 airplanes having one or more struts that failed inspection due to corrosion.

We are not changing the final rule AD action based on these comments.

Conclusion

We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed except for the changes previously discussed and minor editorial corrections. We have determined that these minor corrections:

Costs of Compliance

We estimate that this AD will affect 3,119 airplanes in the U.S. registry.

We estimate the following costs to do the visual inspection: Total cost per Total cost on Labor cost Parts cost airplane U.S. operators 1 workhour x $80 per hour = $80............. Not applicable................. $80 $249,520

We estimate the following costs to do the repetitive ultrasound or radiograph inspection:
Total cost per Labor cost Parts cost airplane 4 workhours x $80 per hour = Not applicable...... $320 $320.

We estimate the following costs to do any necessary replacements that will be required based on the results of the inspections. We have no way of determining the number of airplanes that may need this replacement:
Total cost per airplane to replace Labor cost Parts cost all 4 wing lift struts 4 workhours to replace all 4 struts x Sealed front lift strut: $835 $1,670 + $1,276 + $80 per hour = $320. per strut. Two per airplane = $320 = $3,266. $1,670.
Sealed aft lift strut: $638 per strut. Two per airplane = $1,276..

Original design vented lift struts are no longer manufactured. We have no way of determining the cost associated with obtaining a useable vented strut.

The estimated total cost on U.S. operators includes the cumulative costs associated with AD 20071614 and any actions being added in this AD.

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 AD. 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 the 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 summary of the costs to comply with this AD (and other information as included in the Regulatory Evaluation) and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include ``Docket No. FAA20070286; Directorate Identifier 2007CE086AD'' in your request.
[[Page 9657]]

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:
PART 39AIRWORTHINESS DIRECTIVES
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]
2. The FAA amends Sec. 39.13 by removing Airworthiness Directive (AD) 20071614, Amendment 3915153 (72 FR 45153, August 13, 2007), and adding the following new AD:
20080409 Taylorcraft: Amendment 3915381; Docket No. FAA2007 0286; Directorate Identifier 2007CE086AD.
Effective Date
(a) This AD becomes effective on March 28, 2008.
Affected ADs
(b) This AD supersedes AD 20071614, Amendment 3915153.
Applicability
(c) This AD applies to all serial numbers of Taylorcraft Models A, BC, BCS,

BC65, BCS65, BC1265 (Army L2H), BCS1265, BC12D, BCS12D, BC12D1, BCS12D1, BC12D85, BCS12D85, BC12D485, BCS12D485,
(Army L2G) BF, BFS, BF60, BFS60, BF65, (Army L2K) BF 1265, BFS65, BL, BLS, (Army L2F) BL65, BLS65, (Army L2J) BL1265, BLS1265, 19, F19, F21, F21A, F21B, F22, F22A, F22B, and F22C airplanes that:
(1) Are certificated in any category; and
(2) Do not incorporate sealed wing front lift struts, part number (P/N) MAA815, Univair P/N UAA815, or FAAapproved
equivalent P/N, and sealed aft lift struts, P/N MAA854, Univair P/N UA854, or FAAapproved equivalent P/N, for all struts.

Note 1: This AD applies to all Taylorcraft models listed above, including those models not listed in Taylorcraft Aviation, LLC Service Bulletin No. 2007001, Revision B, dated October 15, 2007. If there are any other differences between this AD and the above service bulletin, this AD takes precedence.

Note 2: For the purposes of this AD, a used strut that has been inspected using the ultrasound or radiograph inspection method, meets the Acceptance/Rejection Criteria specified in Taylorcraft Aviation, LLC Service Bulletin No. 2007001, Revision B, dated October 15, 2007, and is treated with internal corrosion protection, is considered a new strut.
Unsafe Condition
(d) This AD results from our determination that the radiograph inspection method should be used in place of the eddy current inspection method currently required in AD 20071614. We are issuing this AD to detect and correct corrosion or cracks in the left and right wing front and aft lift struts, which could result in failure of the lift strut and lead to inflight separation of the wing with consequent loss of control.
Compliance
(e) To address this problem, you must do the following, unless already done:
Actions Compliance Procedures (1) Visually inspect the left and Within the next 5 hours TIS after Follow Part 1 of the Instructions in right wing front and aft lift August 20, 2007 (the effective date Taylorcraft Aviation, LLC Service struts, (P/N AA815 and P/N AA854, of AD 20071614), unless one of Bulletin No. 2007001, Revision A, or FAAapproved equivalent P/Ns), the following conditions is met: dated August 1, 2007; or along the entire bottom 12 inches (i) The struts have been replaced Taylorcraft Aviation, LLC Service of each strut for cracks and with parts specified in paragraph Bulletin No. 2007001, Revision B, corrosion. (e)(2)(i) of this AD. No further dated October 15, 2007. action is required on those struts. (ii) The struts have been replaced with parts specified in paragraph (e)(2)(ii) of this AD and have been installed for less than 48 months. No visual inspection is required. These parts are now subject to the repetitive inspection requirement specified in paragraph (e)(4) of this AD. (2) If any cracks are found during Before further flight after the Following the Instructions in the visual inspection required in visual inspection required in Taylorcraft Aviation, LLC Service paragraph (e)(1) of this AD, paragraph (e)(1) of this AD. Bulletin No. 2007001, Revision B, replace the cracked strut with the dated October 15, 2007. following applicable strut:
(i) A sealed front lift strut, P/N
MAA815, Univair P/N UAA815, or
FAAapproved equivalent P/N, a
sealed aft lift strut, P/N MAA854,
Univair P/N UA854, or FAAapproved
equivalent P/N. Installing these
lift struts terminates the
repetitive inspections required by
this AD for that strut and no
further action is required.
(ii) A new vented front lift
strut, P/N AA815, a new vented
aft lift strut, P/N AA854, or
FAAapproved equivalent P/Ns,
that is treated with internal
corrosion protection specified
in Taylorcraft Aviation, LLC
Service Bulletin No. 2007001,
Revision B, dated October 15,
2007. Installing one of these
lift struts is subject to the
repetitive inspections required
in paragraph (e)(4) of this AD.
[[Page 9658]]
(3) If corrosion is found during the Before further flight after the Follow Part 2 of the Instructions in inspection required in paragraph visual inspection required in Taylorcraft Aviation, LLC Service (e)(1) of this AD, do an ultrasound paragraph (e)(1) of this AD. Bulletin No. 2007001, Revision B, or radiograph inspection to dated October 15, 2007. All determine if the corrosion exceeds ultrasound or radiograph the Acceptance/Rejection Criteria inspections required by this AD specified in Taylorcraft Aviation, must be done by one of the LLC Service Bulletin No. 2007001, following: Revision B, dated October 15, 2007. (i) A Level II or III inspector certified in the applicable ultrasound or radiograph inspection method using the guidelines established by the American Society of Nondestructive Testing or NAS 410 (formerly MILSTD410); .................................... (ii) An inspector certified to specific FAA or other acceptable government or industry standards, such as Air Transport Association (ATA) Specifications 105Guidelines for Training and Qualifying Personnel in Nondestructive Testing Methods; or .................................... (iii) An FAA Repair Station or a Testing/ Inspection Laboratory qualified to do ultrasound or radiograph inspections. (4) If no corrosion or cracks are (i) Initially inspect within the Follow Part 2 of the Instructions in found during the visual inspection next 3 months after August 20, 2007 Taylorcraft Aviation, LLC Service required in paragraph (e)(1) of (the effective date of AD 200716 Bulletin No. 2007001, Revision B, this AD, or if the inspection 14) or within 48 months after dated October 15, 2007, using the required in paragraph (e)(3) installing a lift strut specified ultrasound or radiograph inspection reveals that the corrosion does not in paragraph (e)(2)(ii) of this AD, method. exceed the Acceptance/Rejection whichever occurs later. Criteria specified in Taylorcraft (ii) Repetitively inspect thereafter Aviation, LLC Service Bulletin No. at intervals not to exceed 48 2007001, Revision B, dated October months, except as required by 15, 2007, repetitively inspect paragraph (e)(4)(iii) of this AD. thereafter using the ultrasound or (iii) If the initial inspection was radiograph inspection method and done using the eddy current method treat with internal corrosion as specified in AD 20071614, the protection until all struts are first ultrasound or radiograph replaced with the sealed struts repetitive inspection must be done specified in paragraph (e)(2)(i) of within the next 24 months after this AD. If any cracks are found or doing the eddy current inspection. corrosion is found that exceeds the Repetitively inspect thereafter at Acceptance/Rejection Criteria intervals not to exceed 48 months specified in Taylorcraft Aviation, using the ultrasound or radiograph LLC Service Bulletin No. 2007001, inspection method.
Revision B, dated October 15, 2007,
during any of the repetitive
inspections required by this AD,
take the necessary corrective
actions as applicable in paragraph
(e)(5) of this AD.
(5) If, during any inspection Before further flight after the Following the Instructions in required in paragraphs (e)(3) or inspection required in paragraph Taylorcraft Aviation, LLC Service (e)(4) of this AD, any cracks are (e)(3) or (e)(4) of this AD. Bulletin No. 2007001, Revision B, found or it is determined that the dated October 15, 2007. corrosion exceeds the Acceptance/
Rejection Criteria specified in
Taylorcraft Aviation, LLC Service
Bulletin No. 2007001, Revision B,
dated October 15, 2007, replace the
lift strut with the applicable lift
strut specified in paragraph
(e)(2)(i) or (e)(2)(ii) of this AD.
(6) Do not install P/N AA815, P/N A As of 5 hours TIS after March 28, Not applicable. A854, or FAAapproved equivalent P/ 2008 the effective date of this AD. N, unless:
(i) Within the last 48 months it has
been inspected using the ultrasound
or radiograph method;
(ii) It meets the Acceptance/
Rejection Criteria; and
(iii) It is treated with
internal corrosion protection
as specified in Taylorcraft
Aviation, LLC Service Bulletin
No. 2007001, Revision B, dated
October 15, 2007.
(7) As a terminating action for the At any time after March 28, 2008 the Not applicable. repetitive inspections required by effective date of this AD. this AD, all vented lift struts (P/
Ns AA815, AA854, and FAAapproved
equivalent P/Ns) may be replaced
with sealed lift struts (P/Ns MA
A815, UAA815, MAA854, UA854, or
FAAapproved equivalent P/Ns).
[[Page 9659]]
Alternative Methods of Compliance (AMOCs)
(f) The Manager, Fort Worth Airplane Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Andrew McAnaul, Aerospace Engineer, ASW150 (c/o MIDO43), 10100 Reunion Place, Suite 650, San Antonio, Texas 78216; telephone: (210) 3083365; fax: (210) 3083370. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.
(g) AMOCs approved for AD 20071614 are approved for this AD. Material Incorporated by Reference
(h) You must use Taylorcraft Aviation, LLC Service Bulletin No. 2007001, Revision A, dated August 1, 2007; and Taylorcraft Aviation, LLC Service Bulletin No. 2007001, Revision B, dated October 15, 2007, to do the actions required by this AD, unless the AD specifies otherwise.
(1) The Director of the Federal Register approved the
incorporation by reference of Taylorcraft Aviation, LLC Service Bulletin No. 2007001, Revision B, dated October 15, 2007, under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) On August 20, 2007 (72 FR 45153, August 13, 2007), the Director of the Federal Register approved the incorporation by reference of Taylorcraft Aviation, LLC Service Bulletin No. 2007 001, Revision A, dated August 1, 2007.
(3) For service information identified in this AD, contact Taylorcraft Aviation, LLC, 2124 North Central Avenue, Brownsville, Texas 78521; telephone: 9569860700.
(4) You may review copies at the FAA, Central Region, Office of the Regional Counsel, 901 Locust, Kansas City, Missouri 64106; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202 7416030, or go to: http://www.archives.gov/federal_register/code_ of_federal_regulations/ibr_locations.html.

Issued in Kansas City, Missouri, on February 13, 2008. David R. Showers,
Acting Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. E83074 Filed 22108; 8:45 am]
BILLING CODE 491013P

FOR FURTHER INFORMATION CONTACT

Andrew McAnaul, Aerospace Engineer, ASW150 (c/o MIDO43), 10100 Reunion Place, Suite 650, San Antonio, Texas 78216; telephone: (210) 3083365; fax: (210) 3083370.