Airworthiness Directives; Great Lakes Aircraft Company, LLC, Models 2T-1A-1 and 2T-1A-2 Airplanes

[Federal Register Volume 69, Number 241 (Thursday, December 16, 2004)]
[Rules and Regulations]
[Pages 75236-75243]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-27521]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-18744; Directorate Identifier 2004-CE-24-AD; 
Amendment 39-13910; AD 2004-25-22]
RIN 2120-AA64


Airworthiness Directives; Great Lakes Aircraft Company, LLC, 
Models 2T-1A-1 and 2T-1A-2 Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA supersedes Airworthiness Directive (AD) 79-20-08, 
which applies to all Great Lakes Aircraft Company, LLC, (Great Lakes) 
Models 2T-1A-1 and 2T-1A-2 airplanes with a Lycoming IO-360-B1F6 or 
AIO-360-B1G6 engine installed. AD 79-20-08 currently requires you to 
inspect the engine induction system and the alternate air door for any 
signs of damage and repairing or replacing any damaged components. AD 
79-20-08 also requires you to inspect the induction system for the 
presence of a drain fitting. If the drain fitting is blocked, 
restricted, or does not exist, AD 79-20-08 requires you to clear the 
fitting or drill a hole in the elbow at the fitting location. This AD 
is the result of the FAA inadvertently omitting Lycoming engine AEIO-
360-B1G6 from the applicability section of AD 79-20-08. Consequently, 
this AD retains the actions required in AD 79-20-08 and adds Lycoming 
engine AEIO-360-B1G6 to the applicability section. We are issuing this 
AD to prevent the aircraft induction system from becoming blocked or 
restricted, which could result

[[Page 75237]]

in engine failure. This failure could lead to loss of control of the 
airplane.

DATES: This AD becomes effective on January 28, 2005.

ADDRESSES: To view the AD docket, go to the Docket Management Facility; 
U.S. Department of Transportation, 400 Seventh Street, SW., Nassif 
Building, Room PL-401, Washington, DC 20590-001 or on the Internet at 
http://dms.dot.gov. The docket number is FAA-2004-18744.

FOR FURTHER INFORMATION CONTACT: Roger Caldwell, Aerospace Engineer, 
Denver Aircraft Certification Office (ACO), Federal Aviation 
Administration (FAA), 26805 E. 68th Ave., Rm 214 Denver, CO 80249-6361; 
telephone: (303) 342-1086; facsimile: (303) 342-1088.

SUPPLEMENTARY INFORMATION:

Discussion

    What events have caused this AD? The alternate air source door on 
the original aircraft configuration of Great Lakes Models 2T-1A-1 and 
2T-1A-2 airplanes was operated by push-pull cable in the cockpit and 
had an induction system drain provision. Later modifications changed 
the configuration of the alternate air source door to automatic 
operation.
    All fuel-injected engines are required to have an alternate air 
source. If the primary induction air source becomes blocked or 
restricted, the lower pressure differential in the induction system 
would overcome a spring tension on the alternate air door and provide a 
secondary airflow path for the engine.
    Inspections of Lycoming engines IO-360-B1F6 and AIO-360-B1G6 
revealed instances of heat distortion, damage, and cracks in the 
alternate air door. Extensive damage to the alternate air door could 
cause pieces to break off and get sucked into the induction system 
blocking the airflow to the engine.
    Additional inspections revealed that some of the affected engines 
did not have an induction system drain to remove fluid and/or moisture 
away from the engine.
    These conditions caused us to issue AD 79-20-08. AD 79-20-08 
currently requires the following on all Great Lakes Models 2T-1A-1 and 
2T-1A-2 airplanes that have a Lycoming engine IO-360-B1F6 or AIO-360-
B1G6 installed:

--Visually inspecting the aircraft induction system drain fitting 
located in the induction elbow below the fuel injector for blockage or 
restriction;
--Clearing the blocked drain hole or drilling a hole in the elbow at 
the fitting location if the drain hole is restricted in the weld area 
or not drilled through the elbow;
--Visually inspecting the alternate air door for damage and repairing 
or replacing any damaged alternate air door; and
--Visually inspecting the aircraft induction system (including the 
filter) for cleanliness, security, and damage and repairing or 
replacing any dirty or damaged components.

    What has happened since AD 79-20-08 to initiate this action? During 
a recent inspection, it was discovered that the Lycoming engine AEIO-
360-B1G6 has the same configuration as Lycoming engines IO-360-B1F6 and 
AIO-360-B1G6.
    What is the potential impact if FAA took no action? If not detected 
and corrected, blockage or restriction of the aircraft induction system 
could cause engine failure. This failure could result in loss of 
control of the airplane.
    Has FAA taken any action to this point? We issued a proposal to 
amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to 
include an AD that would apply to all Great Lakes Models 2T-1A-1 and 
2T-1A-2 airplanes with a Lycoming IO-360-B1F6, AIO-360-B1G6, or AEIO-
360-B1G6 engine installed. This proposal was published in the Federal 
Register as a notice of proposed rulemaking (NPRM) on September 20, 
2004 (69 FR 56175). The NPRM proposed to supersede AD 79-20-08 with a 
new AD that would retain the actions required in AD 79-20-08 and would 
add Lycoming engine AEIO-360-B1G6 to the applicability section.

Comments

    Was the public invited to comment? We provided the public the 
opportunity to participate in developing this AD. We received no 
comments on the proposal or on the determination of the cost to the 
public.

Conclusion

    What is FAA's final determination on this issue? We have carefully 
reviewed the available data and determined that air safety and the 
public interest require adopting the AD as proposed except for minor 
editorial corrections. We have determined that these minor corrections:

--Are consistent with the intent that was proposed in the NPRM for 
correcting the unsafe condition; and
--Do not add any additional burden upon the public than was already 
proposed in the NPRM.

Changes to 14 CFR Part 39--Effect on the AD

    How does the revision to 14 CFR part 39 affect this AD? On July 10, 
2002, the FAA published a new version of 14 CFR part 39 (67 FR 47997, 
July 22, 2002), which governs the FAA's AD system. This regulation now 
includes material that relates to altered products, special flight 
permits, and alternative methods of compliance. This material 
previously was included in each individual AD. Since this material is 
included in 14 CFR part 39, we will not include it in future AD 
actions.

Costs of Compliance

    How many airplanes does this AD impact? We estimate that this AD 
affects 130 airplanes in the U.S. registry.
    What is the cost impact of this AD on owners/operators of the 
affected airplanes? We estimate the following costs to accomplish the 
inspections of the aircraft induction system, the induction system 
drain fitting, and the alternate air door:

----------------------------------------------------------------------------------------------------------------
                                                                   Total cost
            Labor cost                       Parts cost               per        Total cost  on U.S.  operators
                                                                    airplane
----------------------------------------------------------------------------------------------------------------
3 workhours x $65 = $195..........  Not applicable..............         $195  $195 x 130 = $25,350
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to accomplish any necessary repairs 
and/or 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 these repairs and/or replacements:

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               Labor cost                           Parts cost                   Total cost  per component
----------------------------------------------------------------------------------------------------------------
3 workhours per component x $65 = $195.  Approximately $113 per           $195 + 113 = $308
                                          component.
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    What is the difference between the cost impact of this AD and the 
cost impact of AD 79-20-08? The only difference between this AD and AD 
79-20-08 is the correction to the applicability. No additional actions 
are being required. The FAA has determined that this AD action does not 
increase the cost impact over that already required by AD 79-20-08.

Authority for This Rulemaking

    What authority does FAA have for issuing this rulemaking action? 
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

    Will this AD impact various entities? 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.
    Will this AD involve a significant rule or regulatory action? 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 
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. FAA-2004-18744; Directorate Identifier 2004-CE-24-AD'' in 
your request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

0
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 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 FAA amends Sec.  39.13 by removing Airworthiness Directive (AD) 
79-20-08, Amendment 39-3580, and by adding a new AD to read as follows:

2004-25-22 Great Lakes Aircraft Company, LLC: Amendment 39-13910; 
Docket No. FAA-2004-18744; Directorate Identifier 2004-CE-24-AD; 
Supersedes AD 79-20-08; Amendment 39-3580.

When Does This AD Become Effective?

    (a) This AD becomes effective on January 28, 2005.

What Other ADs Are Affected by This Action?

    (b) This AD supersedes AD 79-20-08, Amendment 39-3580.

What Airplanes Are Affected by This AD?

    (c) This AD affects all Model 2T-1A-1 and 2T-1A-2 airplanes that 
have a Lycoming IO-360-B1F6, AIO-360-B1G6, or AEIO-360-B1G6 engine 
installed and are certificated in any category.

What Is the Unsafe Condition Presented in This AD?

    (d) This AD is the result of heat distortion, damage, and cracks 
found in the aircraft induction system on Lycoming IO-360-B1F6, AIO-
360-B1G6, and AEIO-360-B1G6 engines. The actions specified in this 
AD are intended to prevent the aircraft induction system from 
becoming blocked or restricted, which could result in engine 
failure. This failure could lead to loss of control of the airplane.

What Must I Do To Address This Problem?

    (e) To address this problem, you must do the following:

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                Actions                                 Compliance                          Procedures
----------------------------------------------------------------------------------------------------------------
(1) Perform the following:               For all affected airplanes: Inspect      Not applicable.
(i) Visually inspect the aircraft         within the next 25 hours time-in-
 induction system drain fitting located   service (TIS) after January 28, 2005
 in the induction elbow below the fuel    (the effective date of this AD).
 injector for blockage or restriction..   Before further flight, modify the
(ii) If the hole is blocked or            blocked or restricted aircraft
 restricted in the weld area or not       induction system drain fitting.
 drilled through the elbow, open up the
 restricted hole or drill a hole in the
 elbow at the fitting location using a
 No. 10 (.193) drill..

[[Page 75239]]

 
(2) Visually inspect the alternate air   For airplanes previously affected by AD  Not applicable.
 door for distortion, heat damage, and    79-20-08: Initially inspect at the
 cracks. If any damage is found, repair   next scheduled inspection required by
 or fabricate a new door following        AD 79-20-08 or within the next 25
 Figure 1, Figure 2, and Figure 3 in      hours TIS after January 28, 2005 (the
 this AD.                                 effective date of this AD), whichever
                                          occurs later. Repetitively inspect
                                          thereafter at intervals not to exceed
                                          100 hours TIS. For airplanes not
                                          previously affected by AD 79-20-08:
                                          Inspect within the next 25 hours TIS
                                          after January 28, 2005 (the effective
                                          date of this AD). Repetitively inspect
                                          thereafter at intervals not to exceed
                                          100 hours TIS. For all affected
                                          airplanes: After each inspection, if
                                          damage is found during any inspection,
                                          before further flight, repair, replace
                                          the damaged alternate air door.
(3) Visually inspect the aircraft        For airplanes previously affected by AD  Not applicabale.
 induction system for cleanliness of      79-20-08: Initially inspect at the
 the air filter, distortion, security,    next scheduled inspection required by
 and damage from backfire or induction    AD 79-20-08 or within the next 25
 system fire. If the air filter is        hours TIS after January 28, 2005 (the
 dirty, if any distortion, damage, or     effective date of this AD), whichever
 lack of security is found, repair,       occurs later. Repetitively inspect
 replace or modify all affected           thereafter at intervals not to exceed
 components.                              100 hours TIS. For airplanes not
                                          previously affected by AD 79-20-08:
                                          Inspect within the next 25 hours TIS
                                          after January 28, 2005 (the effective
                                          date of this AD). Repetitively inspect
                                          thereafter at intervals not to exceed
                                          100 hours TIS. For all affected
                                          airplanes: After each inspection, if
                                          damage is found during any inspection,
                                          before further flight, repair, replace
                                          or modify any damaged components.
----------------------------------------------------------------------------------------------------------------

May I Request an Alternative Method of Compliance?

    (f) You may request a different method of compliance or a 
different compliance time for this AD by following the procedures in 
14 CFR 39.19. Unless FAA authorizes otherwise, send your request to 
your principal inspector. The principal inspector may add comments 
and will send your request to the Manager, Denver Aircraft 
Certification Office, FAA. For information on any already approved 
alternative methods of compliance, contact Roger Caldwell, Aerospace 
Engineer, Denver ACO, FAA, 26805 E. 68th Ave., Rm 214 Denver, CO 
80249-6361; telephone: (303) 342-1086; facsimile: (303) 342-1088.

May I Get Copies of the Documents Referenced in This AD?

    (g) You may view the AD docket at the Docket Management 
Facility; U.S. Department of Transportation, 400 Seventh Street, 
SW., Nassif Building, Room PL-401, Washington, DC 20590-001 or on 
the Internet at http://dms.dot.gov. The docket number is FAA-2004-
18744.

BILLING CODE 4910-13-P

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    Issued in Kansas City, Missouri, on December 7, 2004.
Sandra J. Campbell,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-27521 Filed 12-15-04; 8:45 am]
BILLING CODE 4910-13-C

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