AD 2000-21-11

This amendment supersedes an existing airworthiness directive (AD), applicable to all Raytheon Model DH.125-1A, -3A, and -400A series airplanes, that currently requires 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 amendment expands the applicability of the existing AD to include additional airplanes, and requires that the actions be accomplished in accordance with revised service information for the newly added airplanes. This amendment is prompted by additional reports indicating that scoring has been detected on the upper fuselage skin around the periphery of the cockpit canopy blister interface. The actions specified by this 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.

The incorporation by reference of Raytheon Aircraft Service Bulletin SB 53-93, dated May 16, 1996, as listed in the regulations, was approved previously by the Director of the Federal Register as of June 6, 1997 (62 FR 24013, May 2, 1997).

Final rule

2000-21-11 RAYTHEON AIRCRAFT COMPANY: Amendment 39-11943. Docket 99-NM-345-AD. Supersedes AD 97-09-12, Amendment 39-10008.

Applicability: Model DH.125, BH.125, and HS.125 series airplanes, as listed in Raytheon Aircraft Service Bulletin SB 53-93, Revision 2, dated April 2000; 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 (e) 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 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:

RESTATEMENT OF THE REQUIREMENTS OF AD 97-09-12:
(a) For Model DH.125-1A, -3A, and -400A series airplanes, as identified in Raytheon Aircraft Service Bulletin SB 53-93, dated May 16, 1996: Within 90 days after June 6, 1997 (the effective date of AD 97-09-12, amendment 39-10008), 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 the service bulletin.

(b) If no scoring is detected during the inspection required by paragraph (a) of this AD, no further action is requiredby 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 Raytheon Aircraft 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.

NEW REQUIREMENTS OF THIS AD:
(d) For airplanes identified in Raytheon Aircraft Service Bulletin SB 53-93, Revision 2, dated April 2000, and not previously identified in paragraph (a) of this AD: 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 Aircraft Service Bulletin SB 53-93, Revision 2, dated April 2000.

(1) If no scoring is detected during the inspection required by paragraph (d) of this AD, no further action is required by this AD.

(2) If any scoring is detected during the inspection required by paragraph (d) of this AD, prior to further flight, determine the location and details of each score, including the edge distance and material thickness, in accordance with the service bulletin.

(i) 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.

(ii) 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 ACO.

NOTE 2: Any inspections and repairs accomplished prior to the effective date in accordance with Raytheon Service Bulletin SB 53-93, Revision 1, dated April 1999, are considered acceptable for compliance for the applicable actions required by this AD.

Alternative Methods of Compliance
(e) 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.

Special Flight Permits
(f) 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 airplaneto a location where the requirements of this AD can be accomplished.

Incorporation by Reference
(g) Except as provided by paragraphs (c)(2) and (d)(2)(ii) of this AD, the actions shall be done in accordance with Raytheon Aircraft Service Bulletin SB 53-93, dated May 16, 1996; and Raytheon Aircraft Service Bulletin SB 53-93, Revision 2, dated April 2000; as applicable.

(1) The incorporation by reference of Raytheon Aircraft Service Bulletin SB 53-93, Revision 2, dated April 2000, is approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.

(2) The incorporation by reference of Raytheon Aircraft Service Bulletin SB 53-93, dated May 16, 1996, was approved previously by the Director of the Federal Register as of June 6, 1997 (62 FR 24013, May 2, 1997).

(3) Copies may be obtained from Raytheon Aircraft Company, Commercial Service Department, P.O. Box 85, Wichita, Kansas 67201-0085. Copies may be inspected at the FAA,Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Effective Date
(h) This amendment becomes effective on November 29, 2000.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 97-09-12, amendment 39-10008 (62 FR 24013, May 2, 1997), which is applicable to all Raytheon Model DH.125-1A, -3A, and -400A series airplanes, was published in the Federal Register on June 16, 2000 (65 FR 37723). The action proposed to continue to 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. The action also proposed to expand the applicability of the existing AD to include additional airplanes and to require that the actions be accomplished in accordance with revised service information for the newly added airplanes.

Comments
Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were submitted in response to the proposal or the FAA's determination of the cost to the public.Conclusion
The FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

Cost Impact
There are approximately 290 airplanes of the affected design in the worldwide fleet. The FAA estimates that 200 airplanes of U.S. registry will be affected by this AD.

The actions that are currently required by AD 97-09-12 and retained in this AD take approximately 4 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the currently required actions on U.S. operators is estimated to be $48,000, or $240 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

Regulatory Impact
The regulations adopted herein will not have a substantial direct effect 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, it is determined that this final rule does not have federalism implications under Executive Order 13132.

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 final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it 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.

39.13 [Amended]
2. Section 39.13 is amended by removing amendment 39-10008 (62 FR 24013, May 2, 1997), and by adding a new airworthiness directive (AD), amendment 39-11943, to read as follows: