[Federal Register Volume 64, Number 79 (Monday, April 26, 1999)]
[Rules and Regulations]
[Pages 20150-20152]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-10180]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-NM-214-AD; Amendment 39-11145; AD 99-09-12]
RIN 2120-AA64


Airworthiness Directives; British Aerospace (Jetstream) Model 
4101 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to all British Aerospace (Jetstream) Model 4101 series 
airplanes, that requires repetitive inspections to detect damage of the 
structure associated with the engine nacelle fairing attached to the 
wing flaps, and repair of any damage found; drilling a new drain hole 
in each engine nacelle fairing; and applying a sealant to the gap 
between the wing flap and engine nacelle fairing. This amendment also 
requires correction of discrepancies, and modification of the wing flap 
structure, which terminates the repetitive inspections. This amendment 
is prompted by reports of fatigue cracks found in the structure that 
attaches the engine nacelle fairing to the wing flaps. The actions 
specified by this AD are intended to prevent such fatigue cracking, 
which could result in the partial or complete separation of the fairing 
from the wing flap, and consequent additional structural damage to the 
airframe and/or reduced controllability of the airplane.

DATES: Effective June 1, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 1, 1999.

ADDRESSES: The service information referenced in this AD may be 
obtained from AI(R) American Support, Inc., 13850 Mclearen Road, 
Herndon, Virginia 20171. This information may be examined at the 
Federal Aviation Administration (FAA), Transport Airplane Directorate, 
Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2110; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to all British Aerospace (Jetstream) 
Model 4101 series airplanes was published as a supplemental notice of 
proposed rulemaking (NPRM) in the Federal Register on February 17, 1999 
(64 FR 7830). That action proposed to require repetitive inspections to 
detect damage of the structure associated with the engine nacelle 
fairing attached to the wing flaps, and repair of any damage found; 
drilling a new drain hole in each engine nacelle fairing; and applying 
a sealant to the gap between the wing flap and engine nacelle fairing. 
That action also proposed to limit the applicability of the AD. The 
action also proposed to require corrective actions for discrepancies, 
and modification of the wing flap structure, which would terminate the 
repetitive inspections.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were submitted in response 
to the proposal or the FAA's determination of the cost to the public.

Conclusion

    The FAA has determined that air safety and the public interest 
require the adoption of the rule as proposed.

Cost Impact

    The FAA estimates that 51 airplanes of U.S. registry will be 
affected by this AD.
    It will take approximately 2 work hours per airplane to perform the 
detailed visual inspection, at an average labor rate of $60 per work 
hour. Based on these figures, the cost impact of the inspection 
required by this AD on U.S.

[[Page 20151]]

operators is estimated to be $6,120, or $120 per airplane, per 
inspection cycle.
    It will take approximately 1 work hour per airplane to drill a 
drain hole and apply primer and sealant, at an average labor rate of 
$60 per work hour. Based on these figures, the cost impact of these 
actions required by this AD on U.S. operators is estimated to be 
$3,060, or $60 per airplane.
    It will take approximately 90 work hours per airplane to accomplish 
the required terminating modification, at an average labor rate of $60 
per work hour. Required parts will cost approximately $2,658 per 
airplane. Based on these figures, the cost impact of the modification 
required by this AD on U.S. operators is estimated to be $410,958, or 
$8,058 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the requirements of this 
AD action, and that no operator would accomplish those actions in the 
future if this AD were not adopted.

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 final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from 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 adding the following new 
airworthiness directive:

99-09-12  British Aerospace Regional Aircraft [Formerly Jetstream 
Aircraft Limited; British Aerospace (Commercial Aircraft) Limited]: 
Amendment 39-11145. Docket 96-NM-214-AD.

    Applicability: Jetstream Model 4101 airplanes, excluding those 
on which Jetstream Modifications JM41575B and JM41575C have been 
accomplished, certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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 (c) 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, unless accomplished 
previously.
    To prevent fatigue cracking in the structure that attaches the 
flap nacelle fairing to the wing flaps, which could result in the 
partial or complete separation of the fairing from the wing flap, 
and consequent additional structural damage to the airframe and/or 
reduced controllability of the airplane, accomplish the following:
    (a) Prior to the accumulation of 1,500 total hours time-in-
service, or within 60 days after the effective date of this AD, 
whichever occurs later, accomplish the requirements of paragraphs 
(a)(1), (a)(2), and (a)(3) of this AD.
    (1) Perform a detailed visual inspection to detect discrepancies 
[cracks, loose rivets and Jo-Bolts, chafing damage at the flap 
trailing edge, and installation of nonstandard parts (as defined in 
Figure 1. of Jetstream Alert Service Bulletin J41-A57-015, Revision 
1, dated August 23, 1996, or Revision 2, dated June 30, 1997)] and 
previous repairs of the flap structure that attaches the flap 
nacelle fairing to each wing flap; in accordance with Jetstream 
Alert Service Bulletin J41-A57-015, Revision 1, dated August 23, 
1996, or Revision 2, dated June 30, 1997. Repeat the inspection 
thereafter at intervals not to exceed 1,500 hours time-in-service 
until the requirements of paragraph (b) of this AD have been 
accomplished.
    (i) Except as provided by paragraph (a)(1)(ii) of this AD, if 
any discrepancy is found, prior to further flight, perform 
corrective action in accordance with Revision 1 or Revision 2 of the 
alert service bulletin.
    (ii) If any discrepancy is found for which Revision 1 or 
Revision 2 of the alert service bulletin specifies to contact the 
manufacturer to obtain a repair scheme: Prior to further flight, 
repair in accordance with a method approved by either the Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate; 
or the Civil Aviation Authority (or its delegated agent).
    (2) Drill a drain hole in the flap nacelle fairing on each wing 
flap, in accordance with Jetstream Alert Service Bulletin J41-A57-
015, dated May 27, 1996, Revision 1, dated August 23, 1996, or 
Revision 2, dated June 30, 1997.
    (3) Apply new primer and sealant to the gap between the wing 
flap and flap nacelle fairing, in accordance with Jetstream Alert 
Service Bulletin J41-A57-015, Revision 1, dated August 23, 1996, or 
Revision 2, dated June 30, 1997.
    (b) Within 3,000 hours time-in-service after the effective date 
of this AD: Modify the wing flap structure in accordance with 
Jetstream Service Bulletin J41-57-017, dated May 9, 1997. 
Accomplishment of this modification constitutes terminating action 
for the repetitive inspection requirements of this AD.

Alternative Methods of Compliance

    (c) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, International Branch, ANM-116. 
Operators shall submit their requests through an appropriate FAA 
Principal Maintenance Inspector, who may add comments and then send 
it to the Manager, International Branch, ANM-116.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

Special Flight Permits

    (d) 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.

Incorporation by Reference

    (e) Except as provided by paragraph (a)(1)(ii) of this AD, the 
actions shall be done in accordance with Jetstream Service Bulletin 
J41-57-017, dated May 9, 1997; Jetstream Alert Service Bulletin J41-
A57-015, Revision 1, dated August 23, 1996; and Jetstream Alert 
Service Bulletin J41-A57-015, Revision 2, dated June 30, 1997, which 
contains the following list of effective pages:

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                                    Revision
                                      level
             Page No.               shown on      Date shown on page
                                      page
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1-3...............................         2  June 30, 1997.
2, 4-9............................         1  Aug. 23, 1996.
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    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 AI(R) American Support, Inc., 
13850 Mclearen Road, Herndon, Virginia 20171. Copies may be 
inspected at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

    Note 3: The subject of this AD is addressed in British 
airworthiness directive 006-05-96.

    (f) This amendment becomes effective on June 1, 1999.

    Issued in Renton, Washington, on April 19, 1999.
D. L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-10180 Filed 4-23-99; 8:45 am]
BILLING CODE 4910-13-P