[Federal Register Volume 64, Number 73 (Friday, April 16, 1999)]
[Rules and Regulations]
[Pages 18804-18806]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-9251]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-CE-29-AD; Amendment 39-11130; AD 99-08-21]
RIN 2120-AA64


Airworthiness Directives; Puritan-Bennett Aero Systems Company 
C351-2000 Series Passenger Oxygen Masks and Portable Oxygen Masks

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
applies to any aircraft equipped with Puritan-Bennett Aero Systems 
Company (Puritan-Bennett) C351-2000 series passenger oxygen masks and 
portable oxygen masks. This AD requires inspecting the passenger and 
portable oxygen masks for tears around the face cushion adjacent to the 
inner mask housing, and replacing or repairing any torn passenger or 
portable oxygen mask. This AD is the result of reports received from 
three airplane manufacturers of defective oxygen masks. The actions 
specified by this AD are intended to prevent reduced oxygen consumption 
when passengers are required to use defective oxygen masks, which could 
result in passenger injury.

DATES: Effective June 2, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 2, 1999.

ADDRESSES: Service information that applies to this AD may be obtained 
from Puritan-Bennett Aero Systems Company, 10800 Pflumm Road, Lenexa, 
Kansas 66215; telephone: (913) 338-9800; facsimile: (913) 338-7353. 
This information may also be examined at the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 98-CE-29-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106; or at the Office of the Federal Register, 
800 North Capitol Street, NW, suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Michael Imbler, Aerospace Engineer, 
FAA, Wichita Aircraft Certification Office, 1801 Airport Road, Room 
100, Mid-Continent Airport, Wichita, Kansas 67209; telephone: (316) 
946-4147; facsimile: (316) 946-4407.

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 all aircraft equipped 
with any Puritan-Bennett C351-2000 series passenger oxygen mask or 
portable oxygen mask having an elastomer cure date between September 
1993 and March 1997 was published in the Federal Register as a notice 
of proposed rulemaking (NPRM) on September 22, 1998 (63 FR 50540). The 
NPRM proposed to require inspecting the oxygen mask face cushion 
adjacent to the inner mask housing for any tear, and, if a tear is 
found, repairing or replacing the passenger or portable oxygen mask 
with one that has an elastomer cure date later than March 1997.
    Accomplishment of the proposed action as specified in the NPRM 
would be required in accordance with Nellcor Puritan-Bennett Service 
Bulletin No. C351-2000-35-1, Revision 2, date of original issue: July, 
1996; date of first revision: February, 1997; date of current revision: 
February, 1998.
    The NPRM was the result of three airplane manufacturers informing 
the FAA that the affected oxygen masks were defective.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Comment Issue No. 1: List in the AD All Passenger Service Units 
That Could Contain the Affected Oxygen Masks

    Two commenters recommend that the FAA provide, in the proposed AD, 
a listing of the passenger service units (PSU) that could contain the 
affected oxygen masks. The commenters state that it would be difficult 
to detect whether one of the affected oxygen masks was in their fleet 
since passenger or portable oxygen masks are not tracked items. As 
written, the proposed AD would require inspecting all aircraft

[[Page 18805]]

and spares in the fleet to determine if the AD applied. The PSU's are 
equipment that is tracked and including a listing of those would allow 
the affected operators to check their logbook to determine AD 
applicability.
    The FAA concurs that listing the PSU's in the proposed AD would 
allow the operators to check the logbook to determine AD applicability. 
However, the affected passenger and portable oxygen masks can be 
installed in any PSU. Therefore, if an operator does not track 
passenger and portable oxygen masks, the FAA knows of no other way to 
assure that the unsafe condition does not go undetected than to inspect 
each PSU to determine if the affected masks are installed.
    No changes to the final rule are required as a result of these 
comments.

Comment Issue No. 2: Cost Impact of the Proposed AD

    Two commenters feel that the FAA's determination of the cost impact 
on U.S. operators of the airplanes that have the affected passenger or 
portable oxygen masks installed is misleading. In particular, these 
comments are as follows:
     One commenter states that the cost to inspect each of his/
her fleet's aircraft to determine if the affected oxygen masks are 
installed on each PSU is 6 workhours per aircraft; and
     The other commenter states that the FAA intended to use 
the cost calculation of 1 workhour per aircraft for labor time, but 
instead multiplied that by the number of masks affected.
    The FAA concurs that the cost impact of the proposed AD is 
misleading. The FAA has no way of determining the exact number of 
affected portable and passenger oxygen masks that would need to be 
either inspected and, if necessary, repaired or replaced on each 
airplane. For this reason, the FAA is writing the Cost Impact section 
in the final rule to account for the cost per mask and not per 
airplane.

Comment Issue No. 3: Make the Inspection Repetitive

    One commenter recommends that the FAA make the proposed inspections 
repetitive. This commenter makes this recommendation based on the 
belief that the unsafe condition is a result of aging and fatigue 
damage to the affected portable and passenger oxygen masks.
    The FAA does not concur that the inspection should be made 
repetitive. The oxygen masks that are unsafe were torn at the factory 
due to a manufacturing defect. This FAA has determined the time range 
of when these torn oxygen masks were manufactured. The proposed AD 
would require repair or replacement of any oxygen mask manufactured 
during a certain time and revealing a tear, and would prohibit future 
installation of any oxygen mask that has a tear.
    Therefore, no changes to the final rule are required as a result of 
these comments.

Comment Issue No. 4: Extend the Compliance Time

    One commenter recommends that the FAA extend the compliance time of 
the proposed AD. This commenter states that the 90 calendar day 
compliance time would be difficult to meet and the economic impact due 
to unnecessary downtime would be significant. The commenter suggests a 
6 calendar month compliance time to coincide with regularly scheduled 
maintenance.
    The FAA concurs. The FAA initially chose 90 calendar days based 
upon a balance between safety and practicality of implementation. The 
commenter presents a strong case for extending the compliance time 
based upon practicality of implementation and the FAA has determined 
that extending to 6 calendar months will not adversely affect aviation 
safety.
    The compliance time of the final rule has been changed accordingly.

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 
the change in the write-up in the Cost Impact section, the change in 
compliance time, and minor editorial corrections. The FAA has 
determined that these changes and the minor editorial corrections will 
not change the meaning of the AD and will not add any additional burden 
upon the public than was already proposed.

Cost Impact

    The FAA estimates that 10,500 oxygen masks will be affected by this 
AD, that it will take approximately 1 workhour per oxygen mask to 
accomplish the inspection and replacement, and that the average labor 
rate is approximately $60 an hour. Puritan-Bennett will repair or 
replace oxygen mask assemblies found defective at no cost to the owner/
operator of any affected aircraft. Based on these figures, the total 
cost impact of the inspection is estimated to be $630,000, or $60 per 
mask. The cost per aircraft will vary based on the number of oxygen 
masks each aircraft has installed and the number that would require 
replacement.

Compliance Time

    The compliance time of this AD is presented in calendar time 
instead of hours time-in-service (TIS).
    The FAA has determined that calendar time compliance is the most 
desirable method because the use of these oxygen masks is not related 
to hours time-in-service. The unsafe condition exists regardless of 
whether the aircraft is in operation. Therefore, to assure that the 
above-referenced condition is corrected within a reasonable period of 
time, a compliance schedule based upon calendar time instead of hours 
TIS is utilized.

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.

[[Page 18806]]

Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding a new airworthiness directive 
(AD) to read as follows:

99-08-21  Puritan-Bennett Aero Systems Company: Amendment 39-11130; 
Docket No. 98-CE-29-AD.

    Applicability: Puritan-Bennett C351-2000 series passenger oxygen 
masks and portable oxygen masks, part numbers as listed below, that 
(1) have elastomer cure dates between September 1993 and March 1997; 
and (2) are installed in aircraft that are certificated in any 
category:

Passenger Masks

C351-2000-00
C351-2000-02
C351-2000-21
C351-2000-38
C351-2000-52
C351-2000-59
C351-2000-63
114006-01
174006-16
174006-30
174006-31
174290-21
174290-22
174290-24
174290-26
174291-21
174291-23
174291-24
174501-00
174504-01 (C351-2000-205)
174505-01 (C351-2000-201)
174506-00 (C351-2000-223)
174509-00 (C351-2000-302)
174510-01 (C351-2000-224)
174510-08 (C351-2000-231)
174510-09 (C351-2000-232)
174510-10 (C351-2000-233)
174510-11 (C351-2000-234)

Drop-Out Box Assemblies

115055-04
115055-10
175011-01
175015-00
175016-00
175105-00
175109-00
175112-10
175112-11
175112-21
175112-90
175205-00
175210-00
175215-01
175222-11
175222-13
175222-20
175222-21
175222-90
175224-00
175242-00
175242-01
175242-02
175303-00
175308-00

Emergency Oxygen Portable Assemblies

176960-13
176960-14
176980-00
176965-SMB2
176965-SCOB2
176965-SMO2
176965-SCMB2

    Note 1: This AD applies to each aircraft equipped with an oxygen 
mask 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 aircraft 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 (d) 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 in the body of this AD, unless 
already accomplished.
    To prevent reduced oxygen consumption when passengers are required 
to use defective oxygen masks, which could result in passenger injury, 
accomplish the following:
    (a) Within the next 6 calendar months after the effective date 
of this AD, inspect the passenger or portable oxygen masks for any 
tear in the face cushion in accordance with the ACCOMPLISHMENT 
INSTRUCTIONS section in Nellcor Puritan-Bennett Service Bulletin No. 
C351-2000-35-1, Revision 2, date of original issue: July, 1996; date 
of first revision: February, 1997; date of current revision: 
February, 1998. The face cushion is adjacent to the inner mask 
housing. If a tear is found, prior to further flight, replace or 
repair the mask in accordance with the service bulletin.
    (b) As of the effective date of this AD, no person may install, 
in any aircraft, Puritan-Bennett C351-2000 series passenger oxygen 
masks and portable oxygen masks that are specified in the 
Applicability section of this AD, unless they have been inspected 
and found airworthy in accordance with paragraph (a) of this AD.
    (c) 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 aircraft to a location where 
the requirements of this AD can be accomplished.
    (d) An alternative method of compliance or adjustment of the 
compliance times that provides an equivalent level of safety may be 
approved by the Manager, Wichita Aircraft Certification Office 
(ACO), 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, 
Kansas 67209. The request shall be forwarded through an appropriate 
FAA Maintenance Inspector, who may add comments and then send it to 
the Manager, Wichita ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Wichita ACO.

    (e) The inspection and replacement or repair required by this AD 
shall be done in accordance with Nellcor Puritan-Bennett Service 
Bulletin No. C351-2000-35-1, Revision 2, date of original issue: 
July, 1996; date of first revision: February, 1997; date of current 
revision: February, 1998. 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 
Puritan-Bennett Aero Systems Company, 10800 Pflumm Road, Lenexa, 
Kansas 66215. 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.
    (f) This amendment becomes effective on June 2, 1999.

    Issued in Kansas City, Missouri, on April 7, 1999.
Carolanne L. Cabrini,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-9251 Filed 4-15-99; 8:45 am]
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