[Federal Register Volume 60, Number 73 (Monday, April 17, 1995)]
[Proposed Rules]
[Pages 19183-19185]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-9349]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 93-NM-105-AD]


Airworthiness Directives; Raytheon Corporate Jets Model BAe 125-
800A and -1000A Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Supplemental notice of proposed rulemaking; reopening of 
comment period.

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SUMMARY: This document revises an earlier proposed airworthiness 
directive (AD), applicable to certain Raytheon Corporate Jets Model BAe 
125-800A and -1000A airplanes, that would have required inspections of 
the wing leading edge skins, including the wing anti-ice fluid 
distribution panel (TKS panel) rebate and radius; repair, if necessary; 
and subsequent corrosion protection treatment. That proposal was 
prompted by reports of corrosion of the wing leading edge skin at the 
interface with the TKS panels. This action revises the proposed rule by 
adding inspections and treatments of the landing/taxiing lamp window 
recess and the stall vane spoiler rebate/radius. The actions specified 
by this proposed AD are intended to prevent reduced structural 
integrity of the wing leading edge section at the interface with the 
TKS panels and stall vane spoilers, which could adversely affect the 
flight characteristics of the airplane.

DATES: Comments must be received by May 26, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 93-NM-105-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 Raytheon Corporate Jets, Inc., 3 Bishops Square Street, 
Albans Road West, Hatfield, Hertfordshire, AL109NE, United Kingdom. 
This information may be examined at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: William Schroeder, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-2148; fax (206) 227-1320.

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 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 93-NM-105-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. 93-NM-105-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to add an airworthiness directive (AD), applicable to 
certain Raytheon Corporate Jets Model BAe 125-800A and -1000A 
airplanes, was published as a notice of proposed rulemaking (NPRM) in 
the Federal Register on August 25, 1993 (58 FR [[Page 19184]] 44795). 
That NPRM would have required inspections of the wing leading edge 
skins, including the wing anti-ice fluid distribution panel (TKS panel) 
rebate and radius; repair, if necessary; and subsequent corrosion 
protection treatment. That NPRM was prompted by reports of exfoliation 
corrosion found on the wing leading edge skin at the interface with the 
TKS panel. This condition, if not corrected, could result in reduced 
structural integrity of the wing leading edge skin and TKS panel 
interface joint, which could adversely affect the flight 
characteristics of the airplane. Exfoliation corrosion also could cause 
in-flight separation of airplane components.
    Since issuance of that NPRM, the manufacturer has reported that 
feedback received from operators who had already accomplished the 
proposed inspections indicates that corrosion has been found in the 
area of the landing/taxiing lamp window assembly recess and stall vane 
spoiler rebate. Such corrosion is due to the ingression of moisture 
through gaps in the sealant that have developed during service. 
Corrosion in this area, if not detected and corrected in a timely 
manner, could result in reduced structural integrity of the wing 
leading edge skin in the vicinity of the landing/taxiing lamp window 
assembly recess and stall vane spoiler rebate, which could adversely 
affect the flight characteristics of the airplane.
    Raytheon Corporate Jets has issued Service Bulletin S.B. 57-77, 
Revision 1, dated October 28, 1993, which describes procedures for 
conducting a one-time detailed visual inspection to detect corrosion of 
the wing leading edge skins, and removal of corrosion, if found. This 
service bulletin also describes procedures for a detailed visual 
inspection, a one-time dye penetrant inspection, removal of exfoliation 
corrosion, and application of an enhanced protective treatment of the 
TKS panel rebate and radius, the landing/taxiing lamp window assembly 
recess, and the stall vane spoiler rebate and radius. The Civil 
Aviation Authority (CAA), which is the airworthiness authority for the 
United Kingdom, classified this revised service bulletin as mandatory.
    The FAA has determined that, in order to adequately address the 
unsafe condition presented by the problems associated with exfoliation 
corrosion in the subject areas, the proposed rule must be revised to 
include inspections of not only the wing leading edge skins and TKS 
panel rebate and radius, but the landing/taxiing lamp window assembly 
recess, and the stall vane spoiler rebate and radius, as well. These 
additional actions would be required to be accomplished in accordance 
with the revised service bulletin described previously.
    The FAA has revised the supplemental NPRM to reflect the corporate 
name change of Corporate Jets to Raytheon Corporate Jets, Inc., and the 
address change of Corporate Jets, Inc., 22070 Broderick Drive, 
Sterling, Virginia 20166 to Raytheon Corporate Jets, Inc., 3 Bishops 
Square Street, Albans Road West, Hatfield, Hertfordshire, AL109NE, 
United Kingdom.
    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.
    Since these changes expand the scope of the originally proposed 
rule, the FAA has determined that it is necessary to reopen the comment 
period to provide additional opportunity for public comment.
    The FAA estimates that 154 Model BAe 125-800A and -1000A airplanes 
of U.S. registry would be affected by this proposed AD. It would take 
approximately 130 work hours per airplane to accomplish the proposed 
inspections, and treatment of the wing leading edge skins (including 
the TKS rebate and radius), and that the average labor rate is $60 per 
work hour. Based on these figures, the total cost impact of the 
proposed AD on U.S. operators is estimated to be $1,201,200, or $7,800 
per airplane.
    The total cost impact figure discussed above is based on 
assumptions that no operator has yet accomplished any of the proposed 
requirements of this AD action, and that no operator would accomplish 
those actions in the future if this AD were not adopted.
    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. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

Raytheon Corporate Jets, Inc. (Formerly DeHavilland, Inc.; Hawker 
Siddeley; British Aerospace, PLC): Docket 93-NM-105-AD.

    Applicability: Model BAe 125-800A and -1000A airplanes, as 
listed in Raytheon Corporate Jets Service Bulletin S.B. 57-77, 
Revision 1, dated October 28, 1993, 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) to request approval [[Page 19185]] 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 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 reduced structural integrity of the wing leading edge 
skin and wing anti-ice fluid distribution panel (TKS panel) 
interface joint, which could adversely affect the flight 
characteristics of the airplane, accomplish the following:
    (a) Accomplish the actions specified in paragraphs (a)(1), 
(a)(2), (a)(3), and (a)(4) of this AD within the time schedule 
indicated in each paragraph, and in accordance with Corporate Jets 
Limited Service Bulletin S.B. 57-77, dated May 20, 1993, or Raytheon 
Corporate Jets Service Bulletin S.B. 57-77, Revision 1, dated 
October 28, 1993:
    (1) Within 24 months since airplane manufacture, or within 12 
months after the effective date of this AD, whichever occurs later, 
perform a detailed visual inspection to detect corrosion of the 
polished surface of the top and bottom leading edge skins on each 
wing, in accordance with either service bulletin.
    (i) If any corrosion is detected and the corrosion is within the 
limits specified in either service bulletin, prior to further 
flight, remove the corrosion in accordance with either service 
bulletin.
    (ii) If any corrosion is detected and that corrosion exceeds the 
limits specified in either service bulletin, prior to further 
flight, repair the wing leading edge skins in accordance with a 
method approved by the Manager, Standardization Branch, ANM-113, 
FAA, Transport Airplane Directorate.
    (2) Prior to further flight after accomplishing the actions 
required by paragraph (a)(1) of this AD, conduct a detailed visual 
inspection to detect corrosion of the wing anti-ice fluid 
distribution panel (TKS panel) rebate and radius, on the top and 
bottom leading edge skin section on each wing, in accordance with 
either service bulletin.
    (i) If any corrosion is detected and the corrosion is within the 
limits specified in either service bulletin, prior to further 
flight, remove the corrosion in accordance with either service 
bulletin.
    (ii) If any corrosion is detected and that corrosion exceeds the 
limits specified in either service bulletin, prior to further 
flight, repair in accordance with a method approved by the Manager, 
Standardization Branch, ANM-113, FAA, Transport Airplane 
Directorate.
    (3) Prior to further flight after accomplishing the actions 
required by paragraph (a)(2) of this AD, conduct a dye penetrant 
inspection to detect corrosion of the TKS panel rebate and radius, 
on the top and bottom leading edge skin section on each wing, in 
accordance with either service bulletin.
    (i) If any corrosion is detected and the corrosion is within the 
limits specified in either service bulletin, prior to further 
flight, remove the corrosion in accordance with either service 
bulletin.
    (ii) If any corrosion is detected and that corrosion exceeds the 
limits specified in the service bulletin, prior to further flight, 
repair in accordance with a method approved by the Manager, 
Standardization Branch, ANM-113, FAA, Transport Airplane 
Directorate.
    (4) Prior to further flight after accomplishing the actions 
required by paragraph (a)(3) of this AD, accomplish both of the 
following actions in accordance with either service bulletin:
    (i) Apply enhanced protective treatment to the TKS panel rebate 
and radius, on the top and bottom leading edge skin section on each 
wing; and
    (ii) Conduct a flight check of the airplane stall warning system 
and stall characteristics.
    (b) Accomplish the actions specified in paragraphs (b)(1), 
(b)(2), and (b)(3) of this AD within the time schedule indicated in 
each paragraph, and in accordance with Raytheon Corporate Jets 
Service Bulletin S.B. 57-77, Revision 1, dated October 28, 1993:

    Note 2: Any inspection specified in paragraph (b)(1), (b)(2), 
and (b)(3) of this AD that was conducted prior to the effective date 
of this AD in accordance with Corporate Jets Limited Service 
Bulletin S.B. 57-77, dated May 20, 1993, is considered to be in 
compliance with this paragraph.
    Note 3: The actions required by paragraph (b) of this AD may be 
accomplished in conjunction with the actions required by paragraph 
(a) within the compliance time required by paragraph (a).

    (1) Within 2 years after the effective date of this AD, conduct 
a detailed visual inspection to detect corrosion of the landing/
taxiing lamp window assembly recess and the stall vane spoiler 
rebate and radius, on the top and bottom leading edge skin section 
on each wing, in accordance with the service bulletin.
    (i) If any corrosion is detected and the corrosion is within the 
limits specified in either service bulletin, prior to further 
flight, remove the corrosion in accordance with the service 
bulletin.
    (ii) If any corrosion is detected and that corrosion exceeds the 
limits specified in either service bulletin, prior to further 
flight, repair in accordance with a method approved by the Manager, 
Standardization Branch, ANM-113, FAA, Transport Airplane 
Directorate.
    (2) Prior to further flight after accomplishing the actions 
required by paragraph (b)(1) of this AD, conduct a dye penetrant 
inspection to detect corrosion of the landing/taxiing lamp window 
assembly recess and the stall vane spoiler rebate and radius, on the 
top and bottom leading edge skin section on each wing, in accordance 
with the service bulletin.
    (i) If any corrosion is detected and the corrosion is within the 
limits specified in either service bulletin, prior to further 
flight, remove the corrosion in accordance with the service 
bulletin.
    (ii) If any corrosion is detected and that corrosion exceeds the 
limits specified in either service bulletin, prior to further 
flight, repair in accordance with a method approved by the Manager, 
Standardization Branch, ANM-113, FAA, Transport Airplane 
Directorate.
    (3) Prior to further flight after accomplishing the actions 
required by paragraph (b)(2) of this AD, accomplish both of the 
following actions in accordance with the service bulletin:
    (i) Apply enhanced protective treatment to the landing/taxiing 
lamp window assembly recess and the stall vane spoiler rebate and 
radius, on the top and bottom leading edge skin section on each 
wing; and
    (ii) Conduct a flight check of the airplane stall warning system 
and stall characteristics.
    (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, Standardization Branch, ANM-113, 
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, 
Standardization Branch, ANM-113.

    Note 4: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (d) Special flight permits may be issued in accordance with 
Secs. 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 April 11, 1995.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-9349 Filed 4-14-95; 8:45 am]
BILLING CODE 4910-13-U