

[Federal Register: October 24, 2007 (Volume 72, Number 205)]
[Rules and Regulations]               
[Page 60228-60231]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr24oc07-2]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28115 Directorate Identifier 2007-CE-045-AD; 
Amendment 39-15235; AD 2007-21-17]
RIN 2120-AA64

 
Airworthiness Directives; British Aerospace Regional Aircraft 
Model HP.137 Jetstream Mk.1, Jetstream Series 200, Jetstream Series 
3101, and Jetstream Model 3201 Airplanes

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

ACTION: Final Rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for the 
products listed above. This AD results from mandatory continuing 
airworthiness information (MCAI) issued by an aviation authority of 
another country to identify and correct an unsafe condition on an 
aviation product. The MCAI describes the unsafe condition as:

    There has been a report of landing gear radius rods suffering 
cracks starting in the flashline near the microswitch boss. Such 
cracks can result in loss of the normal hydraulic system and may 
lead to a landing gear collapse. Main landing gear collapse is 
considered as potentially hazardous/

[[Page 60229]]

catastrophic. This AD mandates additional inspections considered 
necessary to address the identified unsafe condition.

    Note: The cause of this cracking is not related to previous 
cracking of the radius rod cylinder addressed by BAE Systems SB 32-
JA040945 (CAA AD G-2005-0010), however, the consequences of a 
failure are the same.

We are issuing this AD to require actions to correct the unsafe 
condition on these products.

DATES: This AD becomes effective November 28, 2007.
    On November 28, 2007, the Director of the Federal Register approved 
the incorporation by reference of certain publications listed in this 
AD.

ADDRESSES: You may examine the AD docket on the Internet at http://www.regulations.gov
 or in person at Document Management Facility, U.S. 

Department of Transportation, Docket Operations, M-30, West Building 
Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 
20590.

FOR FURTHER INFORMATION CONTACT: Taylor Martin, Aerospace Engineer, 
FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, 
Missouri 64106; telephone: (816) 329-4138; fax: (816) 329-4090.

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
That NPRM was published in the Federal Register on July 6, 2007 (72 FR 
36914). That NPRM proposed to correct an unsafe condition for the 
specified products. The MCAI states:

    There has been a report of landing gear radius rods suffering 
cracks starting in the flashline near the microswitch boss. Such 
cracks can result in loss of the normal hydraulic system and may 
lead to a landing gear collapse. Main landing gear collapse is 
considered as potentially hazardous/catastrophic. This AD mandates 
additional inspections considered necessary to address the 
identified unsafe condition.

    Note: The cause of this cracking is not related to previous 
cracking of the radius rod cylinder addressed by BAE Systems SB 32-
JA040945 (CAA AD G-2005-0010), however, the consequences of a 
failure are the same.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We considered the comment received.

Comment Issue: Compliance Time

    APPH, the original equipment manufacturer of the main landing gear 
of the affected airplanes, expresses concern over being able to supply 
the necessary parts for the mandatory replacement. APPH understands the 
FAA's policy on aging commuter class aircraft, but states that all 
airplanes will have accumulated 8,000 total landings. Therefore, the 
proposed AD would require the replacement on all airplanes within 100 
hours time-in-service (TIS) after the effective date of the AD. APPH 
recommends a compliance time of ``at the next scheduled overhaul.''
    The FAA partially concurs. We understand the problem with supplying 
parts for all airplanes within 100 hours TIS. However, the airplanes 
may not have ``scheduled overhauls,'' since the overhaul program is a 
recommended overhaul program and not a mandatory overhaul program. The 
FAA has determined that changing the 100-hour TIS grace period to 12 
months would eliminate the repetitive inspections and provide 
additional time for operators to acquire the needed parts.
    We are changing the mandatory replacement compliance time in the 
final rule AD action to read ``upon reaching 8,000 total landings on 
the main landing gear radius rods or within the next 12 months after 
the effective date of this AD, whichever occurs later.''

Conclusion

    We reviewed the available data, including the comment received, and 
determined that air safety and the public interest require adopting the 
AD with the changes described previously. We determined that these 
changes will not increase the economic burden on any operator or 
increase the scope of the AD.

Differences Between This AD and the MCAI or Service Information

    We have reviewed the MCAI and related service information and, in 
general, agree with their substance. But we might have found it 
necessary to use different words from those in the MCAI to ensure the 
AD is clear for U.S. operators and is enforceable. In making these 
changes, we do not intend to differ substantively from the information 
provided in the MCAI and related service information.
    We might also have required different actions in this AD from those 
in the MCAI in order to follow FAA policies. Any such differences are 
highlighted in a note within the AD.

 Costs of Compliance

    We estimate that this AD will affect 190 products of U.S. registry. 
We also estimate that it will take about 14 work-hours per product to 
comply with basic requirements of this AD. The average labor rate is 
$80 per work-hour. Required parts will cost about $10,000 per product.
    Based on these figures, we estimate the cost of this AD to the U.S. 
operators to be $2,112,800 or $11,120 per product.

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 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 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.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov
; or in person at the Docket Management Facility 

between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains the NPRM, the regulatory evaluation, 
any comments received, and other information. The

[[Page 60230]]

street address for the Docket Office (telephone (800) 647-5527) is in 
the ADDRESSES section. Comments will be available in the AD docket 
shortly after receipt.

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 FAA amends Sec.  39.13 by adding the following new AD:

2007-21-17 British Aerospace Regional Aircraft: Amendment 39-15235; 
Docket No. FAA-2007-28115; Directorate Identifier 2007-CE-045-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective November 
28, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to HP.137 Jetstream Mk.1, Jetstream Series 
200, Jetstream Series 3101, and Jetstream Model 3201 airplanes, all 
serial numbers, certificated in any category.
    (d) Air Transport Association of America (ATA) Code 32: Landing 
Gear.

Reason

    (e) The mandatory continuing airworthiness information (MCAI) 
states:
    There has been a report of landing gear radius rods suffering 
cracks starting in the flashline near the microswitch boss. Such 
cracks can result in loss of the normal hydraulic system and may 
lead to a landing gear collapse. Main landing gear collapse is 
considered as potentially hazardous/catastrophic. This AD mandates 
additional inspections considered necessary to address the 
identified unsafe condition.

    Note: The cause of this cracking is not related to previous 
cracking of the radius rod cylinder addressed by BAE Systems SB 32-
JA040945 (CAA AD G-2005-0010), however, the consequences of a 
failure are the same.

Actions and Compliance

    (f) Unless already done, do the following actions:
    (1) Initially within the next 3 months after November 28, 2007 
(the effective date of this AD) and repetitively thereafter at 
intervals not to exceed 12 months until the replacement required by 
paragraph (f)(2) or (f)(3) of this AD is done, inspect the main 
landing gear radius rod forged cylinder flashline following the 
accomplishment instructions of British Aerospace Jetstream Series 
3100 and 3200 Service Bulletin 32-JA060741, dated November 1, 2006.
    (2) If cracks are found during any inspection required by this 
AD, before further flight, replace the radius rod assembly with a 
serviceable unit.
    (i) If the radius rod assembly includes the parts described in 
paragraphs (f)(3)(i) and (f)(3)(ii) of this AD, then the repetitive 
inspections of this AD are no longer required.
    (ii) If the radius rod assembly does not include the parts 
described in paragraphs (f)(3)(i) and (f)(3)(ii) of this AD, then 
continue to repetitively inspect at intervals not to exceed 12 
months until you comply with paragraph (f)(3) of this AD.
    (3) Upon reaching 8,000 total landings on the main landing gear 
radius rods or within the next 12 months November 28, 2007(the 
effective date of this AD), whichever occurs later, replace the 
radius rod assembly by installing one of the following part numbers 
(P/N). This terminates the repetitive inspection requirement of this 
AD:
    (i) P/N 1847/A to 1847/L with strike-off 12 or 13, or 1847/M or 
later; and
    (ii) P/N 1862/A to 1862/L with strike-off 12 or 13, or 1862/M or 
later.
    (4) For airplanes under 8,000 total landings on the main landing 
gear radius rods: Before further flight after the initial inspection 
required by paragraph (f)(1) of this AD, do not install a radius rod 
assembly that is not one of the parts specified in paragraphs 
(f)(3)(i) and (f)(3)(ii) of this AD on an affected airplane, unless 
it has been inspected in accordance with paragraph (f)(1) of this 
AD.
    (5) For those airplanes with parts listed in paragraph (f)(3) of 
this AD: Before further flight after installing the parts in 
paragraphs (f)(3)(i) and (f)(3)(ii) of this AD, do not install any 
radius rod assembly that does not incorporate the parts in 
paragraphs (f)(3)(i) and (f)(3)(ii) of this AD.

    Note 1: When a compliance time in this AD is presented in 
landings and you do not keep the total landings, you may multiply 
the total number of airplane hours time-in-service by 0.75 to 
calculate the number of landings for the purposes of doing the 
actions required by this AD.


    Note 2: Maintenance procedures for each radius rod overhaul are 
included in APPH Service Bulletin 1847-32-12 or 1862-32-12, both 
dated September 2006, as applicable. You may do such maintenance 
using the above referenced bulletins or through a fluorescent dye 
penetrant inspection of the cylinder counterbore as specified in 
APPH Component Maintenance Manual (CMM) 32-10-16 at Revision 11 or 
higher.

FAA AD Differences

    Note 3: This AD differs from the MCAI and/or service information 
as follows:
    (1) The MCAI and service bulletin allow the radius rod assembly 
to be repetitively inspected for the life of the airplane and the 
repetitive inspection requirement is terminated if improved design 
parts are installed. Many of the affected airplanes are used in 
commuter operations (14 CFR part 135). The FAA's policy on aging 
commuter class aircraft states that when a modification exists that 
could eliminate or reduce the number of required critical 
inspections, the modification should be incorporated. Therefore, the 
FAA is mandating the replacement of the radius rod assembly with 
improved design parts no later than reaching 8,000 total landings on 
the main landing gear radius rods or within the next 12 months after 
the effective date of this AD, whichever occurs later.

    (2) The MCAI includes a reference to APPH service bulletins as 
an option for maintenance overhaul procedures. Because we do not 
require general maintenance in our ADs, we added a note referencing 
these bulletins as an option to use for overhaul procedures.

Other FAA AD Provisions

    (g) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, 
Standards Staff, 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: Taylor Martin, Aerospace Engineer, FAA, Small 
Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 
64106; telephone: (816) 329-4138; fax: (816) 329-4090. 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.
    (2) Airworthy Product: For any requirement in this AD to obtain 
corrective actions from a manufacturer or other source, use these 
actions if they are FAA-approved. Corrective actions are considered 
FAA-approved if they are approved by the State of Design Authority 
(or their delegated agent). You are required to assure the product 
is airworthy before it is returned to service.
    (3) Reporting Requirements: For any reporting requirement in 
this AD, under the provisions of the Paperwork Reduction Act (44 
U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has 
approved the information collection requirements and has assigned 
OMB Control Number 2120-0056.

Related Information

    (h) Refer to European Aviation Safety Agency (EASA) AD No. 2007-
0087, dated March 30, 2007; and BAE SYSTEMS Jetstream Series 3100 
and 3200 Service Bulletin 32-JA060741, dated November 1, 2006; for 
related information.

Material Incorporated by Reference

    (i) You must use BAE SYSTEMS Jetstream Series 3100 and 3200 
Service Bulletin 32-JA060741, dated November 1, 2006 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 this service information under 5 
U.S.C. 552(a) and 1 CFR part 51.

[[Page 60231]]

    (2) For service information identified in this AD, contact 
British Aerospace (Operations) Limited Trading at British Aerospace 
Regional Aircraft, Prestwick International Airport, Ayrshire KA9 
2RW, Scotland.
    (3) You may review copies at the FAA, Central Region, Office of 
the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 
64106; or at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html
.


    Issued in Kansas City, Missouri, on October 10, 2007.
David R. Showers,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-20364 Filed 10-23-07; 8:45 am]

BILLING CODE 4910-13-P
