[Federal Register Volume 63, Number 42 (Wednesday, March 4, 1998)]
[Proposed Rules]
[Pages 10579-10582]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-5518]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-CE-53-AD]
RIN 2120-AA64


Airworthiness Directives; British Aerospace (Operations) Limited 
HP.137 Mk1, Jetstream Series 200, and Jetstream Model 3101 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Supplemental notice of proposed rulemaking (NPRM); Reopening of 
the comment period.

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

SUMMARY: This document proposes to revise an earlier proposed 
airworthiness directive (AD) that would have superseded Airworthiness 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 (Operations) Limited HP.137 
Mk1 and Jetstream series 200 airplanes, and repairing or replacing any 
part that is cracked beyond certain limits. The proposed AD would have 
required installing improved design MLG fittings, as terminating action 
for the repetitive inspections that are currently required by AD 82-20-
04 R1, and would have incorporated the Jetstream Model 3101 airplanes 
into the Applicability of the AD. The actions specified in the proposed 
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. The Federal Aviation Administration (FAA) 
inadvertently proposed eliminating repetitive inspections of both the 
MLG fitting and MLG support angles in the proposal. Only the 
inspections of the MLG fitting should be eliminated; the inspections of 
the MLG support angle are still valid. Since adding these inspections 
goes beyond the scope of what was originally proposed, the FAA has 
determined that the comment period for the proposal should be reopened 
and the public should have additional time to comment.

DATES: Comments must be received on or before May 8, 1998.

ADDRESSES: Submit comments in triplicate to 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 64106. 
Comments may be inspected at this location between 8 a.m. and 4 p.m., 
Monday through Friday, holidays excepted.
    Service information that applies to this proposed AD may be 
obtained from British Aerospace (Operations) Limited, Prestwick 
International Airport, Ayrshire, KA9 2RW, Scotland; telephone: (44-292) 
79888; facsimile: (44-292) 79703; or AI(R) Ltd., 13850 McLearen Road, 
Herndon, Virginia 22071; telephone: (703) 736-4325; facsimile: (703) 
736-4399. This information also may be examined at the Rules Docket at 
the address above.

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) 426-6932; facsimile: (816) 426-2169.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications should identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this supplemental notice may 
be changed in light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report that summarizes each FAA-public contact concerned 
with the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this supplemental notice must submit a self-
addressed, stamped postcard on which the following statement is made: 
``Comments to Docket No. 95-CE-53-AD.'' The postcard will be date 
stamped and returned to the commenter.

Availability of Supplemental NPRM's

    Any person may obtain a copy of this supplemental NPRM by 
submitting a request to 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 64106.

Events Leading to This Supplemental NPRM

    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 HP.137 Mk1, Jetstream series 200, and Jetstream 
Model 3101 airplanes was published in the Federal Register as a notice 
of proposed rulemaking (NPRM) on March 18, 1997 (62 FR 12771). The NPRM 
proposed to supersede AD 82-20-04 R1 with a new AD that would (1) 
initially retain the requirement 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 the proposed 
action would 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 relevant movement between the nuts and hinge fitting on HP.137 
MK1 and Jetstream series 200 airplanes. This MSB incorporates the 
following effective pages:

[[Page 10580]]



----------------------------------------------------------------------------------------------------------------
                 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 HP.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 HP.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, 18, 19,    Revision 1.......................  September 29, 1987.                 
 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 inadvertently proposed eliminating repetitive inspections 
of both the MLG fitting and MLG support angles in the NPRM. Only the 
inspections of the MLG fitting should be eliminated; the inspections of 
the MLG support angles are still valid.

The Supplemental NPRM

    Because the inspections of the MLG support angles go beyond the 
scope of what was originally proposed in the NPRM, the FAA has 
determined that the comment period for the NPRM should be reopened and 
the public should have additional time to comment.

Differences Between the Proposed AD, the British AD, and Existing 
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. The proposed AD, if adopted, would 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. 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.

Cost Impact

    The FAA estimates that 71 airplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 271 
workhours (inspections: 61 workhours; installation: 210 workhours) per 
airplane to accomplish the proposed actions, and that the average labor 
rate is approximately $60 an hour. Parts to accomplish the proposed AD 
are provided by the manufacturer at no cost to the owners/operators of 
the affected airplanes. Based on these figures, the total cost impact 
of the proposed 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 
HP.137 Mk1, Jetstream series 200, and Jetstream Model 3101 airplane 
owner/operator would incur.
    This figure is also based on the presumption that no affected 
airplane operator has accomplished the proposed installation. This 
action would 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 would be eliminated by 
the proposed action. The FAA estimates these costs to be substantial 
over the long term.
    In addition, British Aerospace (Operations) Limited has informed 
the FAA that parts have been distributed to owners/operators that would 
equip approximately 39 of the affected

[[Page 10581]]

airplanes. Presuming that each set of parts has been installed on an 
affected airplane, the cost impact of the proposed modification upon 
the public would 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 
(Operations) Limited HP.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, 
the proposed AD would not significantly affect a number of small 
entities.
    A copy of the full Cost Analysis and Regulatory Flexibility 
Determination for the proposed 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 proposed herein would 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 
proposal would 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) if promulgated, 
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 draft regulatory evaluation 
prepared for this action has been placed 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, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 14 
CFR part 39 of the Federal Aviation Regulations 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 39-4468, and adding a new AD to read as 
follows:

British Aerospace (Operations) Limited (Type Certificate No. A21EU 
formerly held by Jetstream Aircraft Limited): Docket No. 95-CE-53-
AD. Supersedes 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.        
------------------------------------------------------------------------
HP.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 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 HP.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 3.15 of British Aerospace MSB No. 7/5.

[[Page 10582]]

    (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 HP.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). Perform this 
installation 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,     
 18, 19, 21, 22, 23, 24, 27, 28,                       1987.            
 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 after finding any crack during an 
inspection required by paragraph (b) of this AD; or
    (2) Upon accumulating 20,000 landings on the left and right MLG 
fittings or within the next 50 landings after the effective date of 
this AD (whichever occurs later).
    (d) Incorporating Modification 5218 as required by paragraph (c) 
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.

    Note 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 (Operations) Limited, Prestwick International Airport, 
Ayrshire, KA9 2RW, Scotland; telephone: (44-292) 79888; facsimile: 
(44-292) 79703; or AI(R) Ltd., 13850 McLearen Road, Herndon, 
Virginia 22071; telephone: (703) 736-4325; facsimile: (703) 736-
4399. This service information may be examined at the FAA, Central 
Region, Office of the Regional Counsel, Room 1558, 601 E. 12th 
Street, Kansas.
    (h) This amendment supersedes AD 82-20-04 R1, Amendment 39-4468.

    Issued in Kansas City, Missouri, on February 26, 1998.
Marvin R. Nuss,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-5518 Filed 3-3-98; 8:45 am]
BILLING CODE 4910-13-U