[Federal Register Volume 62, Number 137 (Thursday, July 17, 1997)]
[Rules and Regulations]
[Pages 38206-38208]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-18934]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-NM-136-AD; Amendment 39-10082; AD 97-14-11]
RIN 2120-AA64
Airworthiness Directives; Bombardier Model CL-600-2B19 (Regional
Jet Series 100 and 200) Series Airplanes
agency: Federal Aviation Administration, DOT.
action: Final rule; request for comments.
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summary: This document publishes in the Federal Register an amendment
adopting airworthiness directive (AD) 97-14-11 that was sent previously
to all known U.S. owners and operators of certain Bombardier Model CL-
600-2B19 (Regional Jet Series 100 and 200) series airplanes by
individual notices. This AD requires repetitive inspections to detect
cracks of a certain bulkhead web of the fuselage at certain locations,
and repair, if necessary. This action is prompted by a report of a
pressurization problem during flight, which was caused by fatigue
cracking in the underfloor pressure bulkhead of the fuselage. The
actions specified by this AD are intended to detect and correct such
fatigue cracking, which could result in uncontrolled depressurization
of the airplane and/or reduced structural integrity of the fuselage.
dated: Effective July 22, 1997. To all persons except those persons to
whom it was made immediately effective by emergency AD 97-14-11, issued
on June 27, 1997, which contained the requirements of this amendment.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of Federal Register as of
July 22, 1997.
Comments for inclusion in the Rules Document must be received on or
before September 15, 1997.
addresses: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 97-NM-136-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056.
The applicable service information may be obtained from Bombardier,
Inc., Canadair Aerospace Group, P.O. Box 6087, Station Centre-ville,
Quebec H3C 3G9, Canada. This information may be examined at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington; or at the FAA, Engine and Propeller Directorate, New York
Aircraft Certification Office (ACO), 10 Fifth Street, Third Floor,
Valley Stream, New York; or at the Office of the Federal Register, 800
North Capital Street, NW., suite 700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: George Duckett, Aerospace Engineer, or
Franco Peiri, Aerospace Engineer, Airframe and Propulsion Branch ANE-
171, FAA, Engine and Propeller Directorate, New York Aircraft
Certification Office, 10 Fifth Street, Third Floor, Valley Stream, New
York; telephone (516) 256-7525 or -7526; fax (516) 568-2716.
supplementary information: On June 27, 1997, the FAA issued emergency
AD 97-14-11, which is applicable to certain Bombardier Model CL-600-
2B19 (Regional Jet Series 100 and 200) series airplanes. That action
was prompted by a report of a pressurization problem during flight on a
Model CL-600-2B19 series airplane. Investigation revealed a crack
approximately 14 inches long in the center pressure bulkhead. In
addition, such cracking was found on seven other Model CL-600-2B19
series airplanes. The cause of this cracking has been attributed to
structural fatigue. Fatigue cracking in the underfloor pressure
bulkhead of the fuselage, if not detected and corrected in a timely
manner, could result in uncontrolled depressurization of the airplane
and/or reduced structural integrity of the fuselage.
Explanation of Relevant Service Information
The manufacturer has issued Canadair Regional Jet Alert Service
Bulletin A601R-53-045, dated June 25, 1997, which describes procedures
for repetitive detailed visual inspections to detect cracks at FS
409+128 of a certain bulkhead web of the fuselage at certain locations,
and repair, if necessary. Transport Canada Aviation classified this
alert service bulletin as mandatory and issued Canadian airworthiness
directive CF-97-11, dated June 25, 1997, in order to assure the
continued airworthiness of these airplanes in Canada.
FAA's Conclusions
This airplane model is manufactured in Canada and is type
certificated for operation in the United States under the provisions of
section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and
the applicable bilateral airworthiness agreement. Pursuant to this
bilateral airworthiness agreement, Transport Canada Aviation has kept
the FAA informed of the situation described above. The FAA has examined
the findings of Transport Canada Aviation, reviewed all available
information, and determined that AD action is necessary for products of
this type design that are certificated for operation in the United
States.
Explanation of the Requirements of the Rule
Since the unsafe condition described is likely to exist or develop
on other airplanes of the same type design registered in the United
States, the FAA issued emergency AD 97-14-11 to require repetitive
detailed visual inspections to detect cracks at FS 409+128 of a certain
bulkhead web of the fuselage at certain locations, and repair, if
necessary. This AD also requires that operators report the results of
the detailed visual inspection to the FAA. The inspections are required
to be accomplished in accordance with the alert service bulletin
previously described. The repair is required to be accomplished in
accordance with a method approved by the FAA.
[[Page 38207]]
Operators should note that, while it is not the FAA's normal policy
to allow flight with known cracks, this AD does permit further flight
with cracking within certain limits. The results of a review, conducted
by the manufacturer, revealed that cracking in the underfloor pressure
bulkhead of the fuselage will not result in rapid decompression of the
airplane. Therefore, according to the review, if the crack size limits
are strictly observed and if repetitive inspections are performed at
the required intervals, cracks that grow beyond the limits will be
detected, and corrective action taken, before they can grow to a size
that would create an unacceptable risk of structural failure. Transport
Canada Aviation concurs with the findings of this review. In
consideration of these findings and based on the FAA's criteria for
flight with known cracking, the FAA has determined that further flight
with cracking within certain limits in the center pressure bulkhead is
permissible for an interim period.
This is considered to be interim action. The manufacturer has
advised that it currently is developing a modification that will
positively address the unsafe condition addressed by this AD. Once this
modification is developed, approved, and available, the FAA may
consider additional rulemaking.
Since it was found that immediate corrective action was required,
notice and opportunity for prior public comment thereon were
impracticable and contrary to the public interest, and good cause
existed to make the AD effective immediately by individual notices
issued on June 27, 1997, to all known U.S. owners and operators of
certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 and 200)
series airplanes. These conditions still exist, and the AD is hereby
published in the Federal Register as an amendment to section 39.13 of
the Federal Aviation Regulations (14 CFR 39.13) to make it effective as
to all persons.
Comments Invited
Although this action is in the form of a final rule that involves
requirements affecting flight safety and, thus, was not preceded by
notice and an opportunity for public comment, comments are invited on
this rule. Interested persons are invited to comment on this rule by
submitting such written data, views, or arguments as they may desire.
Communications shall identify the Rules Docket number and be submitted
in triplicate to the address specified under the caption ADDRESSES. All
communications received on or before the closing date for comments will
be considered, and this rule may be amended in light of the comments
received. Factual information that supports the commenter's ideas and
suggestions is extremely helpful in evaluating the effectiveness of the
AD action and determining whether additional rulemaking action would be
needed.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify the 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
AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this rule must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 97-NM-136-AD.'' The postcard will be date stamped and
returned to the commenter.
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.
The FAA has determined that this regulation is an emergency
regulation that must be issued immediately to correct an unsafe
condition in aircraft, and that it is not a ``significant regulatory
action'' under Executive Order 12866. It has been determined further
that this action involves an emergency regulation under DOT Regulatory
Policies and Procedures (44 FR 11034, February 26, 1979). If it is
determined that this emergency regulation otherwise would be
significant under DOT Regulatory Policies and Procedures, a final
regulatory evaluation will be prepared and placed in the Rules Docket.
A copy of it, if filed, 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:
97-14-11 Bombardier, Inc. (Formerly Canadair): Amendment 39-10082.
Docket 97-NM-136-AD.
Applicability: Model CL-600-2B19 (Regional Jet Series 100 and
200) series airplanes, serial numbers 7003 and subsequent;
certificated in any category.
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 (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 detect and correct fatigue cracking in the underfloor
pressure bulkhead of the fuselage, which could result in
uncontrolled depressurization of the airplane and/or reduced
structural integrity of the fuselage, accomplish the following:
(a) Within 20 flight hours after the effective date of this AD,
perform a detailed visual inspection to detect cracks at frame
station (FS) 409+128 of the bulkhead web [part number (P/N)
601R32208-123] of the fuselage, in accordance with Canadair Regional
Jet Alert Service Bulletin A601R-53-045, dated June 25, 1997.
(1) If no crack is detected or if all three of the conditions
specified in paragraphs (a)(1)(i), (a)(1)(ii), and (a)(1)(iii) of
this AD are met, continued flight is allowed. Repeat the detailed
visual inspection thereafter at intervals not to exceed 100 flight
hours.
(i) No more than one crack exists at each corner; and
[[Page 38208]]
(ii) No crack extends under the angles having P/N 601R32208-79
and P/N 601R32208-81 on the aft side of the bulkhead web; and
(iii) No crack exists in angles having P/N 601R32208-79 and P/N
601R32208-81 on the aft side of the bulkhead web.
(2) If any cracking other than that identified in paragraphs
(a)(1)(i), (a)(1)(ii), and (a)(1)(iii) of this AD is detected, prior
to further flight, repair it in accordance with the method approved
by the Manager, New York Aircraft Certification Office (ACO), FAA,
Engine and Propeller Directorate.
(b) Within 10 days after accomplishing the initial and
repetitive detailed visual inspections required by paragraph (a) of
this AD, submit a report of any finding(s) of cracking to the
Manager, New York ACO, telephone (516) 256-7525; fax (516) 568-2716.
Information collection requirements contained in this regulation
have been approved by the Office of Management and Budget (OMB)
under the provisions of the Paperwork Reduction Act of 1980 (44
U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-
0056.
(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, New York ACO. Operators shall
submit their requests through an appropriate FAA Principal
Maintenance Inspector, who may add comments and then send it to the
Manager, New York ACO.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the New York ACO.
(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.
(e) The inspections shall be done in accordance with Canadair
Regional Jet Alert Service Bulletin A601R-53-045, dated June 25,
1997. 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 Transport Canada Aviation.
Copies may be inspected at the FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington; or at the New York
Aircraft Certification Office (ACO), FAA, Engine and Propeller
Directorate; or at the Office of the Federal Register, 800 North
Capitol Street, NW., suite 700, Washington, DC.
(f) This amendment becomes effective on July 22, 1997. All
persons except those persons to whom it was made immediately
effective by emergency AD 97-14-11, issued on June 27, 1997, which
contained the requirements of this amendment.
Issued in Renton, Washington, on July 11, 1997.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 97-18934 Filed 7-16-97; 8:45 am]
BILLING CODE 4910-13-P-M
