AD 2002-03-02

[Federal Register Volume 67, Number 31 (Thursday, February 14, 2002)]
[Rules and Regulations]
[Pages 6846-6850]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 02-3163]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-CE-58-AD; Amendment 39-12643; AD 2002-03-02]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes Airworthiness Directive (AD) 98-13-
03, which currently requires repetitive inspections of the main landing 
gear (MLG) hinge fittings, support angles, and attachment bolts on 
British Aerospace Model HP.137 Jetstream Mk.1, Jetstream Series 200, 
and Jetstream Series 3101 airplanes. AD 98-13-03 also requires eventual 
installation of improved design MLG hinge fittings as terminating 
action for the repetitive inspections of the hinge fittings and 
attachment bolts. AD 98-13-03 specifies repetitive inspections of the 
support angles for those airplanes with the improved design MLG hinge 
fittings installed and exempts from the applicability those airplanes 
with the improved design MLG hinge fittings installed. This AD retains 
the requirements of AD 98-13-03 and removes the applicability exemption 
of those Model HP.137 Jetstream Mk.1 and Jetstream Series 200 airplanes 
with the improved design MLG hinge fittings installed. The actions 
specified by this AD are intended to detect, correct, and prevent 
future fatigue cracking of the MLG, which could result in structural 
failure of the MLG and consequent loss of airplane control during 
takeoff, landing, or taxi operations.

DATES: This AD becomes effective on April 2, 2002.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in the regulations as of April 
2, 2002.

ADDRESSES: You may get the service information referenced in this AD 
from British Aerospace Regional Aircraft, Prestwick International 
Airport, Ayrshire, KA9 2RW, Scotland; telephone: (01292) 479888; 
facsimile: (01292) 479703. You may view this information at the Federal 
Aviation Administration (FAA), Central Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 2000-CE-58-AD, 901 Locust, Room 
506, Kansas City, Missouri 64106; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aerospace Engineer, FAA, 
Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 
64106; telephone: (816) 329-4059; facsimile: (816) 329-4090.

SUPPLEMENTARY INFORMATION:

Discussion

Has FAA Taken any Action on the Main Landing Gear (MLG) Hinge Fittings, 
Support Angles, and Attachment Bolts on British Aerospace Model HP.137 
Jetstream Mk.1, Jetstream Series 200, and Jetstream Series 3101 
Airplanes to This Point?

    On June 8, 1998, FAA issued AD 98-13-03, Amendment 39-10591 (63 FR 
33532, June 19, 1998). This AD currently requires the following on the 
above-referenced airplanes:

--Repetitive inspections of the MLG hinge fitting, support angles, and 
attachment bolts, and repairing or replacing any part that is cracked; 
and
--Eventual installation of improved design MLG hinge fittings, part 
number (P/N) 1379133B1 and 1379133B2 (Modification 5218), as 
terminating action for the repetitive inspections of the hinge fittings 
and attachment bolts. This AD specifies repetitive inspections of the 
support angles for those airplanes with the improved design MLG hinge 
fittings installed. However, the applicability of AD 98-13-03 exempts 
those airplanes with the improved design MLG hinge fittings installed 
from the actions of the AD.

    Accomplishment of these actions is required in accordance with the 
following service information:

--British Aerospace Jetstream Mandatory Service Bulletin (MSB) No. 7/5, 
which includes procedures for inspecting the left and right main 
landing gear hinge attachment nuts to the auxiliary and aft spars for 
signs of relative movement between the nuts and hinge fitting on Model 
HP.137 Jetstream Mk.1 and Jetstream Series 200 airplanes. This MSB 
incorporates the following effective pages:

----------------------------------------------------------------------------------------------------------------
                 Pages                            Revision Level                           Date
----------------------------------------------------------------------------------------------------------------
2 and 4................................  Original Issue.................  March 31, 1982.

[[Page 6847]]

 
1 and 3................................  Revision 1.....................  May 23, 1988.
----------------------------------------------------------------------------------------------------------------

--British Aerospace MSB No. 7/8, which includes procedures for 
inspecting the MLG hinge fitting for cracks, and repairing cracked 
hinge fittings on Model HP.137 Jetstream Mk.1 and Jetstream Series 200 
airplanes. This MSB incorporates the following effective pages:

----------------------------------------------------------------------------------------------------------------
                 Pages                            Revision level                           Date
----------------------------------------------------------------------------------------------------------------
2, 5, 6, 7, and 8......................  Revision 2.....................  January 6, 1983.
1, 3, and 4............................  Revision 3.....................  May 23, 1988.
----------------------------------------------------------------------------------------------------------------

--Jetstream Alert Service Bulletin (ASB) 32-A-JA 850127, which includes 
procedures for inspecting the MLG hinge fitting and support angle for 
cracks on Jetstream Series 3101 airplanes. This ASB incorporates the 
following effective pages:

----------------------------------------------------------------------------------------------------------------
                 Pages                            Revision level                           Date
----------------------------------------------------------------------------------------------------------------
5 through 14...........................  Original Issue.................  April 17, 1985.
1 through 4............................  Revision 2.....................  November 11, 1994.
----------------------------------------------------------------------------------------------------------------

--Jetstream Service Bulletin (SB) 57-JM 5218, which includes procedures 
for installing improved design MLG hinge fittings, P/N 1379133B1 and 
1379133B2 (Modification 5218), on Model HP.137 Jetstream Mk.1, 
Jetstream Series 200, and certain Jetstream Series 3101 airplanes. This 
SB incorporates the following effective pages:

----------------------------------------------------------------------------------------------------------------
                 Pages                            Revision level                           Date
----------------------------------------------------------------------------------------------------------------
11, 12, 17, 18, 19, 21, 22, 23, 24, 27,  Revision 1.....................  September 29, 1987.
 28, 29, 30, and 31.
20.....................................  Revision 3.....................  January 29, 1990.
13 and 14..............................  Revision 4.....................  October 31, 1990.
1 through 10, 15, 16, 25, and 26.......  Revision 5.....................  July 28, 1997.
----------------------------------------------------------------------------------------------------------------

    The actions of AD 98-13-03 are consistent with our aging commuter 
aircraft policy, which briefly states that, when a modification exists 
that could eliminate or reduce the number of required critical 
inspections, the modification should be incorporated. This policy is 
based on our determination that reliance on critical repetitive 
inspections on airplanes utilized in commuter service carries an 
unnecessary safety risk when a design change exists that could 
eliminate or, in certain instances, reduce the number of those critical 
inspections.
    The alternative to installing improved design MLG hinge fittings 
would be to repetitively inspect this area for the life of the 
airplane.

What Has Happened Since AD 98-13-03 To Initiate This Action?

    Since AD 98-13-03 became effective, FAA received comments regarding 
the applicability. The applicability of AD 98-13-03 exempts those 
airplanes with the improved design MLG hinge fittings installed as of 
the effective date of the AD. However, those airplanes that have the 
improved design MLG hinge fittings incorporated after the effective 
date of the AD are subject to repetitive inspections of the MLG support 
angles. Our intent was to require the inspections of the MLG support 
angles regardless of when the improved design MLG hinge fittings are 
incorporated.
    Therefore, we then determined that the exemption of those airplanes 
with the improved design MLG hinge fittings installed should be 
removed, and that all affected airplanes should have the MLG support 
angles repetitively inspected.
    Consequently, 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 certain British Aerospace Models HP.137 Jetstream Mk.1, Jetstream 
Series 200, and Jetstream Series 3101 airplanes. This proposal was 
published in the Federal Register as a notice of proposed rulemaking 
(NPRM) on July 18, 2001 (66 FR 37435). The NPRM proposed to supersede 
AD 98-13-03. The NPRM also proposed to:

--Retain the requirement of repetitively inspecting the main landing 
gear (MLG) hinge fittings, support angles, and attachment bolts and the 
requirement of repairing any cracked part;
--Require eventual installation of improved design MLG hinge fittings 
as terminating action for the repetitive inspections of the hinge 
fittings and attachment bolts; and
--Require repetitive inspections of the MLG support angles on all 
affected airplanes, even those with the improved design MLG hinge 
fittings installed.

    Based on comments received on this NPRM, we made minor changes to 
the proposed action. Another comment indicated that the manufacturer 
was not providing parts to accomplish the proposed action free of 
charge as previously referenced. Because this shifts the cost burden of 
these improved design MLG hinge fittings from the manufacturer to the 
owner/operator, we reopened the comment period for this proposed AD and 
issued a supplemental NPRM.
    This supplemental NPRM was published in the Federal Register on 
November 19, 2001 (66 FR 57890). We received no comments on this 
supplemental NPRM.

[[Page 6848]]

FAA's Determination

What Is FAA's Final Determination on This Issue?

    We carefully reviewed all available information related to the 
subject presented above and determined that air safety and the public 
interest require the adoption of the rule as proposed except for minor 
editorial changes. We have determined that these changes:

--Provide 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.

Cost Impact

How Many Airplanes Does This AD Impact?

    We estimate that this AD affects 71 airplanes in the U.S. registry.

What Is the Cost Impact of This AD on Owners/Operators of the Affected 
Airplanes?

    The FAA estimates that this AD will affect 71 airplanes in the U.S. 
registry. We estimate the following costs to accomplish the actions:

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                                               Labor cost                  Parts cost           Per airplane cost                 Fleet cost
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Initial inspection..................  61 workhours  x  $60 per      Not Applicable.........  $3,660 per airplane...  71 airplanes  x  $3,660 = $259,860.
                                       hour = $3,660.
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Hinge fitting installation..........  210 workhours  x  $60 per     $14,000 per airplane...  $26,600 per airplane..  71 airplanes  x  $26,600 =
                                       hour = $12,600.                                                                $1,888,600.
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Repetitive Support angle inspections  10 workhours  x  $60 per      Not Applicable.........  $600 per airplane per   71 airplanes  x  $600 = $42,600 per
                                       hour = $600 per inspection.                            inspection.             inspection.
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Regulatory Impact

Does This AD Impact Various Entities?

    The regulations adopted herein 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. Therefore, it 
is determined that this final rule does not have federalism 
implications under Executive Order 13132.

Does This AD Involve a Significant Rule or Regulatory Action?

    For the reasons discussed above, I certify that this action (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. A copy of the final evaluation prepared for this 
action is contained in the Rules Docket. A copy of it may be obtained 
by contacting the Rules Docket at the location provided under the 
caption ADDRESSES.

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 39--AIRWORTHINESS 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. FAA amends Sec. 39.13 by removing Airworthiness Directive (AD) 
98-13-03, Amendment 39-10591 (63 FR 33532, June 19, 1998), and by 
adding a new AD to read as follows:

2002-03-02  British Aerospace: Amendment 39-12643; Docket No. 2000-
CE-58-AD; Supersedes AD 98-13-03, Amendment 39-10591.

    (a) What airplanes are affected by this AD? This AD affects the 
following airplane models and serial numbers that are certificated 
in any category:

------------------------------------------------------------------------
                   Model                             Serial No.
------------------------------------------------------------------------
HP.137 Jetstream Mk.1.....................  All serial numbers.
Jetstream Series 200......................  All serial numbers.
Jetstream Series 3101.....................  601 through 695 that do not
                                             have Jetstream Service
                                             Bulletin 57-JM 5218
                                             incorporated (using the
                                             applicable Revision 4 or
                                             Revision 5 pages).
------------------------------------------------------------------------

    (b) Who must comply with this AD? Anyone who wishes to operate 
any of the airplanes identified in paragraph (a) of this AD must 
comply with this AD.
    (c) What problem does this AD address? The actions specified by 
this AD are intended to detect, correct, and prevent future fatigue 
cracking of the main landing gear (MLG), which could result in 
structural failure of the MLG and consequent loss of airplane 
control during takeoff, landing, or taxi operations.

    Note 1: The compliance times of this AD are presented in 
landings. If you do not keep the total number of landings, then you 
may multiply the total number of airplane hours time-in-service 
(TIS) by 0.75.

    (d) What actions must I accomplish to address this problem? To 
address this problem, you must accomplish the following:

[[Page 6849]]



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                                 Actions                                                Compliance                              Procedures
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(1) For the Models HP.137 Jetstream Mk.1 and Jetstream 200 Series         Inspect within the next 50 landings     Use the service information presented
 airplanes, accomplish the following if part number (P/N) 1379133B1 (or    after June 8, 1998 (the effective       in paragraph (h)(1)(i) of this AD.
 FAA-approved equivalent P/N) and P/N 1379133B2 (or FAA-approved           date of AD 98-13-03) or within 200
 equivalent P/N) MLG hinge fittings are not installed. These               landings TIS after the last
 installations incorporate Modification 5218:                              inspection required by 98-13-03,
(i) Inspect the MLG hinge attachment nuts to auxiliary and aft spars on    whichever occurs later, and
 both the left and right MLG for signs of fuel leakage or signs of         thereafter at intervals not to exceed
 relative movement between the nuts and hinge fitting.                     200 landings. Resecure the MLG hinge
(ii) If any signs of fuel leakage or relative movement between the nuts    fitting prior to further flight after
 and hinge fitting are found during any inspection required by paragraph   the applicable inspection.
 (d)(1)(i) of this AD, resecure the MLG hinge fitting to auxiliary spar.
(iii) You may terminate the above inspections when Modification 5218 is
 incorporated. The repetitive inspection of the MLG hinge support angles
 as required by paragraph(d)(2) of this AD are still required.
--------------------------------------------------------------------------------------------------------------------------------------------------------
(2) For all airplanes regardless of the MLG hinge fitting installed,      Inspect upon accumulating 4,000         Inspect in accordance with the service
 inspect the MLG hinge support angles for cracks. If any crack(s) is/are   landings on each MLG hinge fitting or   information presented in paragraph
 found in the support angles, replace the cracked MLG hinge fitting(s)     within the next 50 hours TIS after      (h)(1)(ii) or (h)(1)(iii) of this AD,
 with a P/N 1379133B1 (or FAA-approved equivalent P/N) or P/N 1379133B2    April 2, 2002 (the effective date of    as applicable. Replace in accordance
 (or FAA-approved equivalent P/N) fitting.                                 this AD), whichever occurs later,       with the service information
(i) For all airplanes: you may terminate the repetitive inspection         unless already accomplished, and        presented in paragraph (h)(1)(iv) of
 requirement of paragraphs (d)(1)(i) and (d)(1)(ii) of this AD after       thereafter at intervals not to exceed   this AD.
 incorporating Modification JM5218 on both sides of the airplane.          400 hours TIS. Accomplish any
(ii) For Jetstream 3101 Series airplanes: the repetitive inspections of    necessary replacement prior to
 the MLG support angles required by paragraph (d)(2) of this AD are no     further flight after the inspection
 longer required after incorporating Modification JM5218 on both sides     where the cracked support angle(s) is/
 of the airplane.                                                          are found.
(iii) If Modification JM5218 is incorporated on both sides of a
 Jetstream 3101 Series airplane in accordance with the provisions of AD
 98-13-03, then the intent of paragraph (d)(3) of this AD is met and
 paragraph (d)(4) of this AD is the only paragraph that applies.
(iv) For the affected Models HP.137 Jetstream Mk.1 and Jetstream Series
 200 airplanes: the repetitive inspections of the MLG support angles
 required by paragraph (d)(2) of this AD are still required after
 incorporating Modification JM5218.
--------------------------------------------------------------------------------------------------------------------------------------------------------
(3) For all airplanes, install improved design MLG hinge fittings, P/N    Upon accumulating 20,000 landings on    Inspect in accordance with the service
 1379133B1 (or FAA-approved equivalent P/N) and P/N 1379133B2 (or FAA-     each MLG hinge fitting or within the    information presented in paragraph
 approved equivalent P/N). These installations incorporate Modification    next 50 landings after June 8, 1998     (h)(1)(iv) of this AD.
 JM5218.                                                                   (the effective date of AD 98-13-03),
(i) For all airplanes: you may terminate the repetitive inspection         whichever occurs later, unless
 requirement of paragraphs (d)(1)(i) and (d)(1)(ii) of this AD after       already accomplished.
 incorporating Modification JM5218 on both sides of the airplane.
(ii) For Jetstream 3101 Series airplanes: the repetitive inspections of
 the MLG support angles required by paragraph (d)(2) of this AD are no
 longer required after incorporating Modification JM5218 on both sides
 of the airplane.
(iii) If Modification JM5218 is incorporated on both sides of a
 Jetstream 3101 Series airplane in accordance with the provisions of AD
 98-13-03, then the intent of paragraph (d)(3) of this AD is met and
 paragraph (d)(4) of this AD is the only paragraph that applies.
(iv) For the affected Models HP.137 Jetstream Mk.1 and Jetstream Series
 200 airplanes: the repetitive inspections of the MLG support angles
 required by paragraph (d)(2) of this AD are still required after
 incorporating Modification JM5218.
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(4) Do not install, on any affected airplane, MLG hinge fittings that     As of April 2, 2002 (the effective      Not Applicable.
 are not P/N 1379133B1 (or FAA-approved equivalent P/N) or P/N 1379133B2   date of this AD).
 (or FAA-approved equivalent P/N).
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    (e) Can I comply with this AD in any other way?
    (1) You may use an alternative method of compliance or adjust the 
compliance time if:
    (i) Your alternative method of compliance provides an equivalent 
level of safety; and
    (ii) The Manager, Standards Office, Small Airplane Directorate, 
approves your alternative. Submit your request through an FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Standards Office, Small Airplane Directorate.
    (2) Alternative methods of compliance approved in accordance with 
AD 98-13-03, which is superseded by this AD, are approved as 
alternative methods of compliance with this AD.

    Note 2: This AD applies to each airplane identified in paragraph 
(a) of this AD, regardless of whether it has been modified, altered, 
or repaired in the area subject to the requirements of this AD. For 
airplanes that have been modified, altered, or repaired so that the 
performance of the requirements of this AD is affected, the owner/
operator must request approval for an alternative method of 
compliance in accordance with paragraph (e) of this AD. The request 
should include an

[[Page 6850]]

assessment of the effect of the modification, alteration, or repair 
on the unsafe condition addressed by this AD; and, if you have not 
eliminated the unsafe condition, specific actions you propose to 
address it.

    (f) Where can I get information about any already-approved 
alternative methods of compliance? Contact Doug Rudolph, Aerospace 
Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas 
City, Missouri 64106; telephone: (816) 329-4059; facsimile: (816) 329-
4090.
    (g) What if I need to fly the airplane to another location to 
comply with this AD? The FAA can issue a special flight permit under 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
21.197 and 21.199) to operate your airplane to a location where you can 
accomplish the requirements of this AD.
    (h) Are any service bulletins incorporated into this AD by 
reference?
    (1) Actions required by this AD must be done in accordance with the 
following:
    (i) British Aerospace Jetstream Mandatory Service Bulletin No. 7/5, 
which applies to the affected Models Model HP.137 Jetstream Mk.1 and 
Jetstream Series 200 airplanes and incorporates the following pages:

----------------------------------------------------------------------------------------------------------------
                 Pages                            Revision level                           Date
----------------------------------------------------------------------------------------------------------------
2 and 4................................  Original Issue.................  March 31, 1982.
1 and 3................................  Revision 1.....................  May 23, 1988.
----------------------------------------------------------------------------------------------------------------

    (ii) British Aerospace Mandatory Service Bulletin No. 7/8, which 
applies to the affected Models HP.137 Jetstream Mk.1 and Jetstream 
Series 200 airplanes and incorporates the following effective pages:

----------------------------------------------------------------------------------------------------------------
                 Pages                            Revision level                           Date
----------------------------------------------------------------------------------------------------------------
2, 5, 6, 7, and 8......................  Revision 2.....................  January 6, 1983.
1, 3, and 4............................  Revision 3.....................  May 23, 1988.
----------------------------------------------------------------------------------------------------------------

    (iii) Jetstream Alert Service Bulletin 32-A-JA 850127, which 
applies to the affected Jetstream Series 3101 airplanes and 
incorporates the following effective pages:

----------------------------------------------------------------------------------------------------------------
                 Pages                            Revision level                           Date
----------------------------------------------------------------------------------------------------------------
5 through 14...........................  Original Issue.................  April 17, 1985.
1 through 4............................  Revision 2.....................  November 11, 1994.
----------------------------------------------------------------------------------------------------------------

    (iv) Jetstream Service Bulletin 57-JM 5218, which applies to all of 
the affected airplanes and incorporates the following effective pages:

----------------------------------------------------------------------------------------------------------------
                 Pages                            Revision level                           Date
----------------------------------------------------------------------------------------------------------------
11, 12, 17, 18, 19, 21, 22, 23, 24, 27,  Revision 1.....................  September 29, 1987.
 28, 29, 30, and 31.
20.....................................  Revision 3.....................  January 29, 1990.
13 and 14..............................  Revision 4.....................  October 31, 1990.
1 through 10, 15, 16, 25, and 26.......  Revision 5.....................  July 28, 1997.
----------------------------------------------------------------------------------------------------------------

    (2) The Director of the Federal Register approved this 
incorporation by reference under 5 U.S.C. 552(a) and 1 CFR part 51.
    (3) You can get copies from British Aerospace Regional Aircraft, 
Prestwick International Airport, Ayrshire, KA9 2RW, Scotland. You can 
look at copies at FAA, Central Region, Office of the Regional Counsel, 
901 Locust, Room 506, Kansas City, Missouri, or at the Office of the 
Federal Register, 800 North Capitol Street, NW, suite 700, Washington, 
DC.
    (i) Does this AD action affect any existing AD actions? This 
amendment supersedes AD 98-13-03, Amendment 39-10591.
    (j) When does this amendment become effective? This amendment 
becomes effective on April 2, 2002.

    Issued in Kansas City, Missouri, on February 5, 2002.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 02-3163 Filed 2-13-02; 8:45 am]
BILLING CODE 4910-13-U