[Federal Register Volume 63, Number 118 (Friday, June 19, 1998)]
[Rules and Regulations]
[Pages 33532-33536]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-15884]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-CE-53-AD; Amendment 39-10591; AD 98-13-03]
RIN 2120-AA64


Airworthiness Directives; British Aerospace Model H.P. 137 Mk1, 
Jetstream Series 200, and Jetstream Model 3101 Airplanes.

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This amendment supersedes Airworthiness Directive (AD) 82-20-
04 R1, which currently requires repetitively inspecting the main 
landing gear (MLG) hinge fitting, support angles, and attachment bolts 
on British Aerospace H.P. 137 Mk1 and Jetstream series 200 airplanes, 
and repairing or replacing any part that is cracked beyond certain 
limits. This AD requires installing improved design MLG fittings, as 
terminating action for the repetitive inspections that are currently 
required by AD 82-20-04 R1, and will incorporate the Jetstream Model 
3101 airplanes into the Applicability of the AD. The Federal Aviation 
Administration's policy on aging commuter-class aircraft is to 
eliminate or, in certain instances, reduce the number of certain 
repetitive short-interval inspections when improved parts or 
modifications are available. The actions specified by this AD are 
intended to prevent structural failure of the MLG caused by fatigue 
cracking, which could result in loss of control of the airplane during 
landing operations.

DATES: Effective August 3, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of August 3, 1998.

ADDRESSES: Service information that applies to this AD may be obtained 
from British Aerospace Regional Aircraft, Prestwick International 
Airport, Ayrshire, KA9 2RW, Scotland; telephone: (01292) 479888; 
facsimile: (01292) 671715. This information may also be examined at the 
Federal Aviation Administration (FAA), Central Region, Office of the 
Regional Counsel, Attention: Rules Docket No. 95-CE-53-AD, Room 1558, 
601 E. 12th Street, Kansas City, Missouri 64106; or at the Office of 
the Federal Register, 800 North

[[Page 33533]]

Capitol Street, NW, suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Mr. S.M. Nagarajan, Aerospace 
Engineer, Small Airplane Directorate, Aircraft Certification Service, 
FAA, 1201 Walnut, suite 900, Kansas City, Missouri 64106; telephone: 
(816) 426-6934; facsimile: (816) 426-2169.

SUPPLEMENTARY INFORMATION:

Events Leading to the Issuance of This AD

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to include an AD that would apply to British Aerospace 
(Operations) Limited H.P. 137 Mk1, Jetstream series 200, and Jetstream 
Model 3101 airplanes was published in the Federal Register as a 
supplemental notice of proposed rulemaking (NPRM) on March 4, 1998 (63 
FR 10579). The supplemental NPRM proposed to supersede AD 82-20-04 R1 
with a new AD that would: (1) initially retain the requirements 
contained in AD 82-20-04 R1 of repetitively inspecting the MLG hinge 
fitting, support angles, and attachment bolts, and repairing or 
replacing any part that is cracked; (2) incorporate the Jetstream Model 
3101 airplanes into the Applicability of the AD; and (3) eventually 
require the installation of improved design MLG fittings, part number 
(P/N) 1379133B1 and 1379133B2 (Modification 5218), as terminating 
action for the repetitive inspections. Accomplishment of this action 
would be 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 H.P. 
137 MK1 and Jetstream series 200 airplanes. This MSB incorporates the 
following effective pages:

------------------------------------------------------------------------
             Pages               Revision level            Date         
------------------------------------------------------------------------
2 and 4.......................  Original Issue..  March 31, 1982.       
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 H.P. 137 MK1 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 Model 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 fittings, part number (P/N) 
1379133B1 and 1379133B2 (Modification 5218), on H.P. 137 Mk1, Jetstream 
series 200, and certain Jetstream Model 3101 airplanes. This SB 
incorporates the following effective pages:

------------------------------------------------------------------------
             Pages               Revision level            Date         
------------------------------------------------------------------------
3, 5, 6, 7, 8, 9, 11, 12, 17,   Revision 1......  September 29, 1987.   
 18, 19, 21, 22, 23, 24, 27,                                            
 28, 29, 30, and 31.                                                    
25 and 26.....................  Revision 2......  August 24, 1988.      
10 and 20.....................  Revision 3......  January 29, 1990.     
1, 2, 4, 13, 14, 15, and 16...  Revision 4......  October 31, 1990.     
------------------------------------------------------------------------

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were received on the 
proposed rule or the FAA's determination of the cost to the public.

The FAA's Determination

    After careful review of all available information related to the 
subject presented above, the FAA has determined that air safety and the 
public interest require the adoption of the rule as proposed except for 
minor editorial corrections. The FAA has determined that these minor 
corrections will not change the meaning of the AD and will not add any 
additional burden upon the public than was already proposed.

Differences Between This AD, the British AD, and AD 82-20-04 R1

    AD 82-20-04 R1 allows continued flight if cracks are found in the 
MLG hinge fitting support angles that propagate no further than the 
tooling holes. The applicable service bulletin specifies replacement of 
the support angles only if cracks are found exceeding this limit, as 
does British AD 015-05-85. This AD will not allow continued flight if 
any crack is found. FAA policy is to disallow airplane operation when 
known cracks exist in primary structure, unless the ability to sustain 
ultimate load with these cracks is proven, and then this is only 
considered a temporary solution until a design correction is developed 
and incorporated. The main landing gear is considered primary 
structure, and the FAA has not received any analysis to prove that 
ultimate load can be sustained with cracks in this area.

The FAA's Aging Commuter Aircraft Policy

    The actions required by this AD are consistent with the FAA's 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 the FAA's 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. In determining what inspections are 
critical, the FAA considers (1) the safety consequences of the airplane 
if the known problem is not detected by the inspection; (2) the 
reliability of the inspection such as the probability of not detecting 
the known problem; (3) whether the inspection area is difficult to 
access; and (4) the possibility of damage to an adjacent structure as a 
result of the problem.
    The alternative to installing improved design MLG fitting would be 
to repetitively inspect this area for the life of the airplane.

Cost Impact

    The FAA estimates that 71 airplanes in the U.S. registry will be 
affected by this AD, that it will take approximately 271 workhours 
(inspections: 61 workhours; installation: 210 workhours) per airplane 
to accomplish these actions, and that the average labor rate is 
approximately $60 an hour. Parts to accomplish this AD are provided by 
the

[[Page 33534]]

manufacturer at no cost to the owners/operators of the affected 
airplanes. Based on these figures, the total cost impact of this AD on 
U.S. operators is estimated to be $1,154,460, or $16,260 per airplane. 
This figure only takes into account the cost of the initial inspections 
and inspection-terminating modification and does not take into account 
the cost of repetitive inspections. The FAA has no way of determining 
the number of repetitive inspections each H.P. 137 Mk1, Jetstream 
series 200, and Jetstream Model 3101 airplane owner/operator will 
incur.
    This figure is also based on the presumption that no affected 
airplane operator has accomplished this installation. This action will 
eliminate the repetitive inspections required by AD 82-20-04 R1. The 
FAA has no way of determining the operation levels of each individual 
owner/operator of the affected airplanes, and cannot determine the 
repetitive inspection costs that will be eliminated by this action. The 
FAA estimates these costs to be substantial over the long term.
    In addition, British Aerospace has informed the FAA that parts have 
been distributed to owners/operators that will equip approximately 39 
of the affected airplanes. Presuming that each set of parts has been 
installed on an affected airplane, the cost impact of this modification 
upon the public will be reduced $634,140 from $1,154,460, to $520,320.

Regulatory Flexibility Determination and Analysis

    The Regulatory Flexibility Act of 1980 (RFA) was enacted by 
Congress to ensure that small entities are not unnecessarily or 
disproportionally burdened by government regulations. The RFA requires 
government agencies to determine whether rules would have a 
``significant economic impact on a substantial number of small 
entities,'' and, in cases where they would, conduct a Regulatory 
Flexibility Analysis in which alternatives to the rule are considered. 
FAA Order 2100.14A, Regulatory Flexibility Criteria and Guidance, 
outlines FAA procedures and criteria for complying with the RFA. Small 
entities are defined as small businesses and small not-for-profit 
organizations that are independently owned and operated or airports 
operated by small governmental jurisdictions. A ``substantial number'' 
is defined as a number that is not less than 11 and that is more than 
one-third of the small entities subject to a proposed rule, or any 
number of small entities judged to be substantial by the rulemaking 
official. A ``significant economic impact'' is defined by an annualized 
net compliance cost, adjusted for inflation, which is greater than a 
threshold cost level for defined entity types.
    FAA Order 2100.14A, Regulatory Flexibility Criteria and Guidance, 
defines a small entity as ``a small business or small not-for-profit 
organization which is independently-owned and operated and has no more 
than a specified number of employees or aircraft.'' For operators of 
aircraft for hire (those entities that are affected by parts 121, 127, 
and 135 of the Federal Aviation Regulations (14 CFR parts 121, 127, and 
135)), the size threshold specified in FAA Order 2100.14A is nine 
aircraft.
    There are only nine different operators of British Aerospace H.P. 
137 MK1, Jetstream series 200, and Jetstream Model 3101 airplanes. Of 
these nine, only four operate less than nine airplanes. Because 4 is a 
number that is less than 11 and the rulemaking official has not 
determined this number to be substantial, this AD would not 
significantly affect a number of small entities.
    A copy of the full Cost Analysis and Regulatory Flexibility 
Determination for this action may be examined at the FAA, Central 
Region, Office of the Regional Counsel, Attention: Rules Docket No. 95-
CE-53-AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri.

Regulatory Impact

    The regulations adopted herein will not have substantial direct 
effects 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, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    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, pursuant to 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. Section 39.13 is amended by removing Airworthiness Directive 
(AD) 82-20-04 R1, Amendment No. 39-4468, and by adding a new AD to read 
as follows:

98-13-03  British Aerospace (Type Certificate No. A21EU formerly 
held by Jetstream Aircraft Limited): Amendment 39-10591; Docket No. 
95-CE-53-AD; Supersedes AD 82-20-04 R1, Amendment 39-4468.

    Applicability: The following model and serial number airplanes, 
certificated in any category, that do not have improved design main 
landing gear (MLG) fittings, part number (P/N) 1379133B1 and 
1379133B2 (Modification 5218), installed in accordance with 
Jetstream Service Bulletin (SB) 57-JM 5218:

------------------------------------------------------------------------
                Model                             Serial Nos.           
------------------------------------------------------------------------
H.P. 137 MK1.........................  All serial numbers.              
Jetstream Series 200.................  All serial numbers.              
Jetstream Model 3101.................  601 through 695.                 
------------------------------------------------------------------------

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, 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 (f) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated after the effective date of 
this AD, unless already accomplished.
    To prevent structural failure of the MLG caused by fatigue 
cracking, which could

[[Page 33535]]

result in loss of control of the airplane during landing operations, 
accomplish the following:

    Note 2: The compliance times of this AD are presented in 
landings. If the total number of airplane landings is not kept or is 
unknown, hours time-in-service (TIS) may be used by multiplying the 
total number of airplane hours TIS by 0.75.

    (a) For the H.P. 137 MK1 and Jetstream series 200 airplanes, 
within the next 50 landings after the effective date of this AD or 
within 200 landings after the last inspection required by AD 82-20-
04 R1 (superseded by this AD), whichever occurs first, and 
thereafter at intervals not to exceed 200 landings, accomplish the 
following in accordance with British Aerospace Mandatory Service 
Bulletin (MSB) No. 7/5, which incorporates the following pages:

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

    (1) Inspect the MLG hinge attachment nuts to auxiliary and aft 
spars on both the left and right MLG for signs of fuel leakage or signs 
of relative movement between the nuts and hinge fitting.
    (2) If any signs of fuel leakage or relative movement between the 
nuts and hinge fitting are found, prior to further flight, resecure the 
MLG hinge fitting to auxiliary spar in accordance with actions 3.8 
through 3.16 of British Aerospace MSB No. 7/5.
    (b) Upon accumulating 4,000 landings on the left and right MLG 
fittings or within the next 50 landings after the effective date of 
this AD, whichever occurs later, and thereafter at intervals not to 
exceed 400 landings, inspect the MLG hinge support angles for cracks in 
accordance with the following, as applicable:
    (1) For the H.P. 137 MK1 and Jetstream series 200 airplanes: 
British Aerospace MSB 7/8, which 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.         
------------------------------------------------------------------------

    (2) For the Jetstream Model 3101 airplanes:
    Jetstream Alert Service Bulletin (ASB) 32-A-JA 850127, which 
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.    
------------------------------------------------------------------------

    (c) Install improved design MLG fittings, part number (P/N) 
1379133B1 and 1379133B2 (Modification 5218), as applicable. Perform 
these installations at the applicable compliance time presented below 
(paragraphs (c)(1) and (c)(2) of this AD). Accomplish this installation 
in accordance with Jetstream Service Bulletin (SB) 57-JM 5218, which 
incorporates the following effective pages:

------------------------------------------------------------------------
             Pages               Revision level            Date         
------------------------------------------------------------------------
3, 5, 6, 7, 8, 9, 11, 12, 17,   Revision 1......  September 29, 1987.   
 18, 19, 21, 22, 23, 24, 27,                                            
 28, 29, 30, and 31.                                                    
25 and 26.....................  Revision 2......  August 24, 1988.      
10 and 20.....................  Revision 3......  January 29, 1990.     
1, 2, 4, 13, 14, 15, and 16...  Revision 4......  October 31, 1990.     
------------------------------------------------------------------------

    (1) Prior to further flight on any fitting found cracked during an 
inspection required by paragraph (b) of this AD; and
    (2) Upon accumulating 20,000 landings on the left MLG fitting or 
within the next 50 landings after the effective date of this AD 
(whichever occurs later), unless already accomplished as required by 
paragraph (c)(1) of this AD; and
    (3) Upon accumulating 20,000 landings on the right MLG fitting or 
within the next 50 landings after the effective date of this AD 
(whichever occurs later), unless already accomplished as required by 
paragraph (c)(1) of this AD.
    (d) Incorporating both P/N 1379133B1 and P/N 1379133B2 MLG fittings 
(Modification 5218) as required by paragraph (c), including all 
subparagraphs, of this AD terminates the repetitive inspection 
requirement of paragraph (a) of this AD. The repetitive inspections of 
the MLG support angles required by paragraph (b) of this AD are still 
required.
    (e) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
21.197 and 21.199) to operate the airplane to a location where the 
requirements of this AD can be accomplished.
    (f) An alternative method of compliance or adjustment of the 
initial or repetitive compliance times that provides an equivalent 
level of safety may be approved by the Manager, Small Airplane 
Directorate, 1201 Walnut, suite 900, Kansas City, Missouri 64106.
    (1) The request shall be forwarded through an appropriate FAA 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Small Airplane Directorate.
    (2) Alternative methods of compliance approved in accordance with 
AD 82-20-04 R1 (superseded by this action) are not considered approved 
as alternative methods of compliance with this AD.

    4Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Small Airplane Directorate.

    (g) Questions or technical information related to the service 
information referenced in this AD should be directed to British 
Aerospace Regional Aircraft, Prestwick International Airport, Ayrshire, 
KA9 2RW, Scotland; telephone: (01292) 479888; facsimile: (01292) 
671715. This service information may be examined at the FAA, Central 
Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.
    (h) The inspections, modifications, and installations required by 
this AD shall be done in accordance with the following:

--British Aerospace Jetstream Mandatory Service Bulletin No. 7/5, which 
incorporates the following pages:

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

--British Aerospace Mandatory Service Bulletin No. 7/8, which 
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 32-A-JA 850127, which incorporates 
the following effective pages:

------------------------------------------------------------------------
             Pages               Revision level            Date         
------------------------------------------------------------------------
5 through 14..................  Original Issue..  April 17, 1985.       

[[Page 33536]]

                                                                        
1 through 4...................  Revision 2......  November 11, 1994.    
------------------------------------------------------------------------

--Jetstream Service Bulletin 57-JM 5218, which incorporates the 
following effective pages:

------------------------------------------------------------------------
             Pages               Revision level            Date         
------------------------------------------------------------------------
3, 5, 6, 7, 8, 9, 11, 12, 17,   Revision 1......  September 29, 1987.   
 18, 19, 21, 22, 23, 24, 27,                                            
 28, 29, 30, and 31.                                                    
25 and 26.....................  Revision 2......  August 24, 1988.      
10 and 20.....................  Revision 3......  January 29, 1990.     
1, 2, 4, 13, 14, 15, and 16...  Revision 4......  October 31, 1990.     
------------------------------------------------------------------------

    This incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. 
Copies may be obtained from British Aerospace Regional Aircraft, 
Prestwick International Airport, Ayrshire, KA9 2RW, Scotland. Copies 
may be inspected at the FAA, Central Region, Office of the Regional 
Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at 
the Office of the Federal Register, 800 North Capitol Street, NW, suite 
700, Washington, DC.
    (i) This amendment supersedes AD 82-20-04 R1, mendment 39-4468.
    (j) This amendment becomes effective on August 3, 998.

    Issued in Kansas City, Missouri, on June 8, 1998.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 98-15884 Filed 6-18-98; 8:45 am]
BILLING CODE 4910-13-U