[Federal Register Volume 60, Number 160 (Friday, August 18, 1995)]
[Proposed Rules]
[Pages 43089-43091]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-20505]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 95-NM-56-AD]
Airworthiness Directives; Cessna Model 441, 500, 550, and 560
Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the adoption of a new airworthiness
directive (AD) that is applicable to certain Cessna Model 441, 500,
550, and 560 series airplanes. This proposal would require replacement
of outflow/safety valves with serviceable valves. This proposal is
prompted by a report of cracking and subsequent failure of outflow
safety valves in the pressurization system. The actions specified by
the proposed AD are intended to prevent such cracking and subsequent
failure of the outflow/safety valves, which could result in rapid
decompression of the airplane.
DATES: Comments must be received by October 16, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 95-NM-56-AD, 1601 Lind Avenue, SW., Renton,
Washington 98055-4056. Comments may be inspected at this location
between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal
holidays.
-The service information referenced in the proposed rule may be
obtained from Allied Signal, Inc., Controls and Accessories, 1110 North
Oracle Road, Tucson, Arizona 85737-9588. This information may be
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue,
SW., Renton, Washington; or at the FAA, Transport Airplane Directorate,
Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard,
Lakewood, California.
FOR FURTHER INFORMATION CONTACT: Walter Eierman, Aerospace Engineer,
Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft
Certification Office, 3960 Paramount Boulevard, Lakewood, California
90712; telephone (310) 627-5336; fax (310) 627-5210.
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 shall 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 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 summarizing each FAA-public contact concerned with
the substance of this
[[Page 43090]]
proposal will be filed in the Rules Docket. -
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this notice must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 95-NM-56-AD.'' The postcard will be date stamped and
returned to the commenter.
Availability of NPRMs -
Any person may obtain a copy of this NPRM by submitting a request
to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules
Docket No. 95-NM-56-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The FAA has received a report of the failure of a safety valve in
the pressurization system on a Learjet Model 31A airplane. Failure of
the valve resulted in depressurization of the cabin. Investigation
revealed that the poppets of certain outflow/safety valves were
cracked. These discrepant valves, including the safety valve installed
on the incident airplane, had been manufactured since January 1, 1989.
Certain valves manufactured since that date have been found to be
susceptible to cracking due to an improper molding process. Cracking in
the poppets of the outflow/safety valves in the pressurization system
can result in an open valve with an effective flow area of 4.4 square
inches; additionally, the valve may close and remain closed. This
condition, if not corrected, could result in cracking and subsequent
failure of the airflow/safety valves, which could lead to rapid
decompression of the airplane. -
On March 9, 1995, the FAA issued a proposed rule (Docket 94-NM-211-
AD, 60 FR 14231, March 16, 1995), applicable to certain Learjet Model
24, 25, 31, 35, 36, and 55 series airplanes and Learjet Model 28 and 29
airplanes, to address the unsafe condition described previously. The
outflow/safety valves installed on these airplanes are similar to the
valves installed on Cessna Model 441, 500, 550, and 560 series
airplanes. Therefore, the FAA has determined that the latter airplane
models also are subject to the unsafe condition described previously. -
The FAA has reviewed and approved the following Allied Signal
Aerospace Service Bulletins: -
1. Service Bulletin 103576-21-4054, dated January 30, 1995 (for
Cessna Model 441 series airplanes); -
2. Service Bulletin 103576-21-4056, dated January 30, 1995 (for
Cessna Model 500 and 550 series airplanes); and
3. Service Bulletin 103648-21-4055, dated January 30, 1995 (for
Cessna Model 560 series airplanes).
These service bulletins describe procedures for replacement of
certain discrepant outflow/safety valves with serviceable valves.
Since an unsafe condition has been identified that is likely to
exist or develop on other products of this same type design, the
proposed AD would require replacement of certain discrepant outflow/
safety valves with serviceable valves. The actions would be required to
be accomplished in accordance with the service bulletins described
previously.
As a result of recent communications with the Air Transport
Association (ATA) of America, the FAA has learned that, in general,
some operators may misunderstand the legal effect of AD's on airplanes
that are identified in the applicability provision of the AD, but that
have been altered or repaired in the area addressed by the AD. The FAA
points out that all airplanes identified in the applicability provision
of an AD are legally subject to the AD. If an airplane has been altered
or repaired in the affected area in such a way as to affect compliance
with the AD, the owner or operator is required to obtain FAA approval
for an alternative method of compliance with the AD, in accordance with
the paragraph of each AD that provides for such approvals. A note has
been included in this notice to clarify this long-standing requirement.
There are approximately 150 Cessna Model 441, 500, 550, and 560
series airplanes of the affected design in the worldwide fleet. The FAA
estimates that 120 airplanes of U.S. registry would be affected by this
proposed AD, that it would take approximately 12 work hours per
airplane to accomplish the proposed actions, and that the average labor
rate is $60 per work hour. Based on these figures, the total cost
impact of the inspection requirement of this proposal on U.S. operators
is estimated to be $86,400, or $720 per airplane. However, the
manufacturer has advised that it will provide replacement parts at no
cost to the operator and will reimburse operators for the labor costs
of the required removal and replacement.
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 proposed
regulation (1) is not a ``significant regulatory action'' under
Executive Order 12866; (2) is not a ``significant rule'' under the 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 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, Safety.
The Proposed Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration proposes to amend
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), 40101, 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
Cessna Aircraft Company: Docket 95-NM-56-AD.
Applicability: Model 441, 500, 550, and 560 series airplanes;
equipped with Allied Signal outflow/safety valves; as identified in
Allied Signal Aerospace Service Bulletins 103576-21-4054, 103576-21-
4056, and 103648-21-4055, all dated January 30, 1995; 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 use the authority
provided in paragraph (c) of this AD to request approval from the
FAA. This approval may address either no action, if the current
configuration eliminates the unsafe condition; or different actions
necessary to address the unsafe condition described in
[[Page 43091]]
this AD. Such a request should include an assessment of the effect of
the changed configuration on the unsafe condition addressed by this
AD. In no case does the presence of any modification, alteration, or
repair remove any airplane from the applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent cracking and subsequent failure of the outflow/safety
valves, which would result in rapid decompression of the airplane,
accomplish the following:
(a) Within 18 months after the effective date of this AD,
replace the outflow/safety valve in accordance with Allied Signal
Aerospace Service Bulletin 103576-21-4054 (for Model 441 series
airplanes), 103576-21-4056 (for Model 500 and 550 series airplanes),
or 103648-21-4055 (for Model 560 series airplanes), all dated
January 30, 1995, as applicable.
(b) As of the effective date of this AD, no person shall install
an outflow/safety valve, having a part number and serial number
identified in Allied Signal Aerospace Service Bulletin 103576-21-
4054 (for Model 441 series airplanes), 103576-21-4056 (for Model 500
and 550 series airplanes), or 103648-21-4055 (for Model 560 series
airplanes), all dated January 30, 1995, on any airplane unless that
valve is considered to be serviceable in accordance with the
applicable service bulletin.
(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, Los Angeles Aircraft Certification
Office (ACO), FAA, Transport Airplane Directorate. Operators shall
submit their requests through an appropriate FAA Principal
Maintenance Inspector, who may add comments and then send it to the
Manager, Los Angeles ACO.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Los Angeles 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.
Issued in Renton, Washington, on August 14, 1995.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-20505 Filed 8-17-95; 8:45 am]
BILLING CODE 4910-13-U
