[Federal Register Volume 61, Number 29 (Monday, February 12, 1996)] [Rules and Regulations] [Pages 5275-5277] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 96-1521] ======================================================================= ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. 94-NM-162-AD; Amendment 39-9504; AD 96-03-07] Airworthiness Directives; Beech Model 400, 400A, and MU-300-10 Airplanes AGENCY: Federal Aviation Administration, DOT. ACTION: Final rule. ----------------------------------------------------------------------- SUMMARY: This amendment adopts a new airworthiness directive (AD), applicable to certain Beech Model 400, 400A, and MU-300-10 airplanes, that requires installation of an improved adjustment mechanism on the flightcrew seats and replacement of the existing aluminum seat reinforcement assemblies with steel assemblies. This amendment is prompted by reports of incomplete latching of the existing adjustment mechanism and cracked reinforcement assemblies, which could result in sudden shifting of a flightcrew seat. The actions specified by this AD are intended to prevent such shifting of a flightcrew seat, which could impair the flightcrew's ability to control the airplane. DATES: Effective March 13, 1996. The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of March 13, 1996. ADDRESSES: The service information referenced in this AD may be obtained from Raytheon Aircraft Company, P.O. Box 85, Wichita, Kansas 67201-0085. This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 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; or at the Office of the Federal Register, 800 North Capitol Street NW., suite 700, Washington, DC. FOR FURTHER INFORMATION CONTACT: Larry Engler, Aerospace Engineer, Airframe Branch, ACE-118W, 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: A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain Beech Model 400, 400A, and MU-300-10 airplanes was published in the Federal Register on May 25, 1995 (60 FR 27705). That action proposed to require installing an improved adjustment mechanism on the flightcrew seats, and replacing the existing aluminum seat reinforcement assemblies with steel assemblies. Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the single comment received. The commenter suggests that the corrective action for this proposed AD is much simpler than that specified in the proposal. The commenter perceives the problem to be that some pilots may not carefully check the security and locking of their seats after making an adjustment. Therefore, the seat can slide during taxi, climb out, or turning. The commenter believes the corrective action involves flightcrew awareness; the flightcrew should be responsible in determining if the seat is locked into position by attempting to make the seat slide out of position by rocking the seat fore and aft. The commenter suggests that, if this method were employed, the costs associated with the accomplishment of the actions specified in this proposed AD would not be necessary. The commenter agrees that if the seat locking pins are worn or the mechanism bent, those parts should be repaired. The FAA does not concur with the commenter's suggestion that attempting to make the seat slide out of position by rocking the seat fore and aft sufficiently addresses the unsafe condition. In this case, the FAA has received several reports of incomplete latching of the existing adjustment mechanism, and cracking of the aluminum seat reinforcement assemblies. Cracking of the aluminum seat reinforcement assemblies is an indicator of a [[Page 5276]] structurally weak design, and this is the unsafe condition the FAA is addressing in this AD action. The FAA has the authority to issue an AD when it is found that an unsafe condition is likely to exist or develop on other products of the same type design. The FAA finds that installing an improved seat tracking adjustment mechanism and replacing the aluminum seat reinforcement assemblies with steel assemblies adequately, and appropriately, addresses this unsafe condition. This same commenter also questions the FAA's original certification basis of the subject airplane relative to the seat mechanism. The commenter asks whether the FAA ``made a mistake'' by certifying the airplane with these seat mechanisms installed. In response to this, the FAA points out that an airplane's type design is approved only after the FAA makes a determination that it complies with all applicable airworthiness requirements. In adopting and maintaining those requirements, the FAA has made the determination that they establish an appropriate level of safety. However, actual in- service experience (as well as other factors, such as manufacturers' fatigue testing, etc.) may reveal problems in an airplane or its components that were not envisioned or predictable at the time of its type certification. When these problems create an unsafe condition, this means that the original level of safety is no longer being achieved. When actions or procedures are identified that will positively correct the unsafe condition and restore the airplane to its original level of safety, an AD is the appropriate vehicle for mandating that such actions be accomplished. After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed. There are approximately 169 Beech Model 400, 400A, and MU-300-10 airplanes of the affected design in the worldwide fleet. The FAA estimates that 121 airplanes of U.S. registry will be affected by this AD, that it will take approximately 24 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will cost approximately $700 per airplane. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $258,940, or $2,140 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 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 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 USC 106(g), 40113, 44701. Sec. 39.13 [Amended] 2. Section 39.13 is amended by adding the following new airworthiness directive: 96-03-07 Beech Aircraft Corporation: Amendment 39-9504. Docket 94- NM-162-AD. Applicability: Model 400 airplanes, serial numbers RJ-1 through RJ-65 inclusive; Model 400A airplanes, serial numbers RK-1 through RK-93 inclusive; and Model MU-300-10 airplanes, serial numbers A1001SA through A1011SA inclusive; 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 (b) 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 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 controllability of the airplane due to a shifting of the flightcrew seat during flight, accomplish the following: (a) Within 200 hours time-in-service after the effective date of this AD, install an improved adjustment mechanism on the flightcrew seat, and replace the existing aluminum seat reinforcement assemblies with steel assemblies, in accordance with Beechcraft Service Bulletin No. 2536, Revision 1, dated April 1995. (b) 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 Aircraft Certification Office (ACO), FAA, Small 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, 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. (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 airplane to a location where the requirements of this AD can be accomplished. (d) The installation and replacement shall be done in accordance with Beechcraft Service Bulletin No. 2536, Revision 1, dated April 1995. (NOTE: The issue date of Service Bulletin No. 2536 is indicated only on page 1; no other page of the document is dated.) 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 Raytheon Aircraft Company, 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, Small Airplane Directorate, 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. (e) This amendment becomes effective on March 13, 1996. [[Page 5277]] Issued in Renton, Washington, on January 23, 1996. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 96-1521 Filed 2-9-96; 8:45am] BILLING CODE 4910-13-U