[Federal Register Volume 62, Number 34 (Thursday, February 20, 1997)]
[Proposed Rules]
[Pages 7731-7733]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-4197]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 96-NM-190-AD]
RIN 2120-AA64


Airworthiness Directives; Raytheon Model DH 125-1A, -3A, and -
400A 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 all Raytheon Model DH 125-1A, -3A, 
and -400A series airplanes. This proposal would require a one-time 
inspection to detect scoring of the upper fuselage skin around the 
periphery of the cockpit canopy blister interface, and repair, if 
necessary. This proposal is prompted by reports indicating that scoring 
of the upper fuselage skin had been detected in that area. The actions 
specified by the proposed AD are intended to detect and correct scoring 
of the upper fuselage skin around the periphery of the cockpit canopy 
blister interface, which could result in reduced structural integrity 
of the fuselage, and consequent cabin depressurization.

DATES: Comments must be received by March 31, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 96-NM-190-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 Aircraft Company, Commercial Service Department, 
P.O. Box 85, Wichita, Kansas 67201-0085. This information may be 
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, 
SW., Renton, Washington; or at the FAA, Small Airplane Directorate, 
Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, 
Mid-Continent Airport, Wichita, Kansas.


[[Page 7732]]


FOR FURTHER INFORMATION CONTACT: Larry Engler, Aerospace Engineer, 
Airframe Branch, ACE-120W, FAA, Small Airplane Directorate, Wichita 
Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-
Continent Airport, Wichita, Kansas 67209; telephone (316) 946-4122; fax 
(316) 946-4407.

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 96-NM-190-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. 96-NM-190-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports indicating that scoring of the upper 
fuselage skin around the periphery of the cockpit canopy blister 
interface has occurred on Raytheon Model DH 125-1A, -3A, and -400A 
series airplanes. Investigation revealed that the scoring was due to 
the use of sharp instruments to remove excess sealant during the four-
year inspection cycle of the fuselage skin under the canopy blister. 
Use of sharp instruments to remove excess sealant is contrary to the 
instructions contained in Chapter 20 of the Airplane Maintenance Manual 
(AMM). Scoring of the upper fuselage skin around the periphery of the 
cockpit canopy blister interface, if not corrected, could result in 
reduced structural integrity of the fuselage skin, and consequent cabin 
depressurization.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Raytheon Service Bulletin SB.53-
93, dated May 16, 1996, which describes procedures for a one-time 
detailed visual inspection to detect scoring of the upper fuselage skin 
around the periphery of the cockpit canopy blister interface. The 
service bulletin also describes repair procedures for scoring that is 
within the specified limits.

Explanation of Requirements of Proposed Rule

    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 a one-time detailed visual inspection to 
detect scoring of the upper fuselage skin around the periphery of the 
cockpit canopy blister interface, and repair, if necessary. The visual 
inspection and repair of scoring that is within certain limits would be 
required to be accomplished in accordance with the service bulletin 
described previously. Repair of scoring that is outside certain limits 
would be required to be accomplished in accordance with a method 
approved by the FAA.

Cost Impact

    There are approximately 200 Model DH 125-1A, -3A, and -400A series 
airplanes of the affected design in the worldwide fleet. The FAA 
estimates that 115 airplanes of U.S. registry would be affected by this 
proposed AD, that it would take approximately 4 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 cost impact of the 
proposed AD on U.S. operators is estimated to be $27,600, or $240 per 
airplane.
    The 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.

Regulatory Impact

    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), 40113, 44701.


Sec. 39.13  [Amended]

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

Raytheon Aircraft Company (Formerly Beech, Raytheon Corporate Jets, 
British Aerospace, Hawker Siddeley, et al.): Docket 96-NM-190-AD.

    Applicability: All Model DH 125-1A, -3A, and -400 series 
airplanes, 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 (d) of 
this AD. The request should include an assessment of

[[Page 7733]]

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.
    Note 2: Raytheon Model DH 125-1B, -3B, and -400B series 
airplanes are similar in design to the airplanes that are subject to 
the requirements of this AD and, therefore, also may be subject to 
the unsafe condition addressed by this AD. However, as of the 
effective date of this AD, those models are not type certificated 
for operation in the United States. Airworthiness authorities of 
countries in which the Model DH 125-1B, -3B, and -400B series 
airplanes are approved for operation should consider adopting 
corrective action, applicable to those models, that is similar to 
the corrective action required by this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To detect and correct scoring of the upper fuselage skin around 
the periphery of the cockpit canopy blister interface, which could 
result in reduced structural integrity of the fuselage skin, and 
consequent cabin depressurization; accomplish the following:
    (a) Within 90 days after the effective date of this AD, perform 
a one-time detailed visual inspection to detect scoring of the upper 
fuselage skin around the periphery of the cockpit canopy blister 
interface, in accordance with Raytheon Service Bulletin SB.53-93, 
dated May 16, 1996.
    (b) If no scoring is detected during the inspection required by 
paragraph (a) of this AD, no further action is required by this AD.
    (c) If any scoring is detected during the inspection required by 
paragraph (a) of this AD, prior to further flight, determine the 
maximum location and details of each score, including the edge 
distance and material thickness, in accordance with Service Bulletin 
SB.53-93, dated May 16, 1996.
    (1) If any scoring is found that is within the limits specified 
in the service bulletin, prior to further flight, repair in 
accordance with the service bulletin.
    (2) If any scoring is found that is outside the limits specified 
in the service bulletin, prior to further flight, repair in 
accordance with a method approved by the Manager, Wichita Aircraft 
Certification Office (ACO), FAA, Small Airplane Directorate.
    (d) 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, Wichita ACO. Operators shall submit 
their requests through an appropriate FAA Principal Maintenance 
Inspector, who may add comments and then send it to the Manager, 
Wichita ACO.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Wichita ACO.

    (e) 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 February 13, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-4197 Filed 2-19-97; 8:45 am]
BILLING CODE 4910-13-U