AD 99-21-30

This amendment adopts a new airworthiness directive (AD), applicable to all Raytheon Model Mitsubishi MU-300 airplanes, that requires revising the Airplane Flight Manual (AFM) to provide pilots with certain operating procedures during icing conditions, and to limit the maximum flaps position for flight in icing conditions or landing after an icing encounter. The amendment also requires installing an ice detector, and accomplishing a corresponding AFM revision to address its operation. For certain airplanes, the amendment requires converting the airplane configuration or modifying the warning horn system of the landing gear; and revising the AFM to specify flaps 10 degrees as a normal landing flap configuration. The actions specified by this AD are intended to prevent uncommanded nose-down pitch at certain flap settings during icing conditions.

Final rule

99-21-30 RAYTHEON AIRCRAFT COMPANY (Formerly Beech): Amendment 39-11376. Docket 96-NM-210-AD. Issued October 15, 1999.
Applicability: All Model Mitsubishi MU-300 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 otherwise 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 prevent uncommanded nose-down pitch at certain flap settings during icing conditions, accomplish the following:

(a) For all airplanes: Within 20 days after December 28, 1994 (the effective date of AD 94-25-10, amendment 39-9094), revise the Limitations Section and Normal Procedures Section of the FAA-approved Airplane Flight Manual (AFM) to include the following statement. This may be accomplished by inserting a copy of this AD in the AFM.

"ICING CONDITIONS

If icing conditions are encountered during flight, no greater than 10 degrees flaps may be utilized for landing unless the following conditions are met:

1. The icing conditions were encountered for less than 10 minutes, and the Ram Air Temperature (RAT) during such encounter was warmer than -8 degrees C.
Or

2. A RAT of +5 degrees C or warmer is observed during approach and landing. If either of the above two conditions are met, 30 degrees flaps may be utilized for landing.

Otherwise:

Flaps (landing flaps setting).....................................10 degrees
Land Select (LAND SEL) Switch ...........................Flaps 10 degrees
Use landing data for 10 degrees flaps from Appendix 1 of this AD."

(b) For Diamond I airplanes, as identified in Mitsubishi MU-300 Service Bulletin No. 30-007, dated January 12, 1996: Within 2 years after the effective date of this AD, accomplish the requirements of paragraphs (b)(1) through (b)(4) of this AD:

(1) Install an ice detector in accordance with Mitsubishi MU-300 Service Bulletin No. 30-007, dated January 12, 1996.

(2) Revise the Introduction, Operating Limitations, Emergency Procedures, Abnormal Procedures, Normal Procedures, Performance, and Weight and Balance Sections of the FAA-approved AFM to address the operation of the ice detector system. This may be accomplished by inserting a copy of Airplane Flight Manual Supplement M300-1003, dated December6, 1995, in the AFM.

(3) Accomplish either paragraph (b)(3)(i) or (b)(3)(ii) of this AD.

(i) Convert the airplane from the Diamond I configuration to the Diamond IA configuration in accordance with Mitsubishi MU-300 Diamond Service Recommendation SR 71-001, Revision 2, dated June 1, 1984; and accomplish the AFM revision required by paragraph (c)(3) of this AD. Or

(ii) Modify the warning horn system of the landing gear in accordance with Attachment 1 of Mitsubishi MU-300 Service Bulletin No. 30-007, dated January 12, 1996.

(4) Revise the Operating Limitations, Emergency Procedures, Abnormal Procedures, Normal Procedures, Performance, and Weight and Balance Sections of the AFM to limit the maximum flap position to flaps 10 degrees for flight in icing conditions or landing after an icing encounter, to allow landing flaps of 30 degrees if the icing encounter meets certain criteria, and to specify flaps 10 degrees as a normal landing flap configuration. This maybe accomplished by inserting a copy of Diamond I Flight Manual, Revision 9, dated January 5, 1996, in the AFM.

(c) For Diamond IA airplanes: Within 2 years after the effective date of this AD, accomplish the requirements of paragraphs (c)(1), (c)(2), and (c)(3) of this AD.

(1) Install an ice detector in accordance with Mitsubishi MU-300 Service Bulletin No. 30-007, dated January 12, 1996.

(2) Revise the Introduction, Operating Limitations, Emergency Procedures, Abnormal Procedures, Normal Procedures, Performance, and Weight and Balance Sections of the FAA-approved AFM to address the operation of the ice detector system. This may be accomplished by inserting a copy of Airplane Flight Manual Supplement M300-1003, dated December 6, 1995, in the AFM.

(3) Revise the Operating Limitations, Emergency Procedures, Abnormal Procedures, Normal Procedures, and Performance Sections of the AFM to limit the maximum flap position to flaps 10 degrees for flight in icing conditions or landing after an icing encounter, and to allow landing flaps of 30 degrees if the icing encounter meets certain criteria. This may be accomplished by inserting a copy of Mitsubishi MU-300 Diamond IA Airplane Flight Manual, Revision 9, dated January 5, 1996, in the AFM.

(d) Accomplishment of the requirements of paragraph (b) or (c) of this AD, as applicable, constitutes terminating action for the requirements of AD 94-25-10, amendment 39-9094 [and paragraph (a) of this AD.] Following accomplishment of paragraph (b) or (c) of this AD, as applicable, the AFM revision required by paragraph (a) of this AD may be removed from the AFM.

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 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.

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 airplane to a location where the requirements of this AD can be accomplished.

Incorporation by Reference
(g) Except as provided by paragraphs (a), (b)(2), (b)(4), (c)(2), and (c)(3) of this AD, the actions shall be done in accordance with Mitsubishi MU-300 Service Bulletin No. 30-007, dated January 12, 1996; and Mitsubishi MU-300 Diamond Service Recommendation SR 71-001, Revision 2, dated June 1, 1984. Mitsubishi MU-300 Diamond Service Recommendation SR 71-001, Revision 2, dated June 1, 1984, contains the following list of effective pages:Page Number
Revision Level
Shown on Page
Date
Shown on Page
List of Effective Pages
2
June 1, 1984
Pages 1, 2

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, Manager Service Engineering, Hawker Customer Support 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 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.

(h) This amendment becomes effective on November 30, 1999.

FOR FURTHER INFORMATION CONTACT:
Tina Miller, Aerospace Engineer, Flight Test Branch, ACE-117W, FAA, Small Airplane Directorate, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209; telephone (316) 946-4168; fax (316) 946-4407.

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 all Mitsubishi MU-300 series airplanes was published in the Federal Register on February 26, 1997 (62 FR 8648). That action proposed to require revising the Airplane Flight Manual (AFM) to provide pilots with certain operating procedures during icing conditions, and to limit the maximum flaps position for flight in icing conditions or landing after an icing encounter. (That AFM revision was previously required in AD 94-25-10.)

That action also proposed to require installing an ice detector, and accomplishing a corresponding AFM revision to address its operation. For certain airplanes, that action proposed to require converting the airplane configuration or modifying the warning horn system of the landing gear; and revising the AFM to specify flaps 10 degrees as a normal landing flap configuration.

FAAResponse to Comments
Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

Request to Withdraw the Proposal
One commenter states that the requirements of the proposal would require the addition of expensive and unnecessary equipment that does not provide any benefit to safety. The commenter also states that any competent pilot would already have the anti-ice systems engaged before the annunciator light of the proposed ice detector would illuminate. Additionally, the commenter asserts that during past experience in operating several different Raytheon BE-400 series airplanes, the annunciator of the ice detector, which is identical to the proposed ice detector, did not illuminate during icing conditions. Therefore, the commenter concludes that the proposed installation of the ice detector would not provide any additional warning or benefit to the pilot. Based on those comments, the FAA infers that the commenter is requesting that the proposal be withdrawn.

The FAA does not concur that the proposal should be withdrawn. The FAA considers that installation of the ice detector and the corresponding Airplane Flight Manual revision, as proposed, will alert pilots to turn on the airplane anti-ice systems in advance of the time that ice may be visually detected (especially during night operations). Extensive FAA flight testing on a similar airplane model (Beechcraft Model 400A series airplanes) indicated that the ice detector consistently and reliably illuminated during icing encounters. Since the advance notice provided by the ice detector will permit the pilot to engage the anti-ice system in a timely manner, accumulation of ice on the horizontal tail will be reduced. Therefore, the FAA has determined that the requirements of this AD are appropriate and necessary.

Request to Require the Manufacturer Cover Costs
This same commenter requests that, if the FAA insists on issuing the proposed rule, the FAA hold the manufacturer responsible for covering costs associated with the installation of the ice detector. The commenter states that if the kit is to be required, this would indicate a flaw in the design of the airplane. The commenter advises that the manufacturer has agreed to cover the cost of the ice detector for the Raytheon BE-400 series airplanes.

The FAA does not concur with the commenter's request that the FAA require the manufacturer to cover the cost of installing the ice detector. The FAA recognizes that the general obligation of the operator to maintain aircraft in an airworthy condition is vital, but sometimes expensive. The FAA considers that, in the interest of maintaining safe aircraft, prudent operators would accomplish the required actions even if they were not required to do so by the AD. However, the manufacturer, not the FAA, determines if the manufacturer will cover the cost of implementing aparticular action. Therefore, no change in this regard is necessary to the final rule.

Conclusion
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.

Cost Impact
The FAA estimates that 89 Model MU-300 airplanes of U.S. registry will be affected by this proposed AD.

The AFM revision that is currently required by AD 94-25-10, amendment 39-9094 (59 FR 64112, December 13, 1994), for Model MU-300 airplanes takes approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact on U.S. operators of the currently required AFM revision will be $5,340, or $60 per airplane.

The ice detector installation that is required in this AD action for all airplanes will take approximately 80 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts will cost approximately $7,000 per airplane. Based on these figures, the cost impact on U.S. operators of the installation required by this AD is estimated to be $1,050,200, or $11,800 per airplane.

The new AFM revisions that are required by this AD action for all airplanes will take approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these estimated figures, the cost impact on U.S. operators of the new AFM revisions will be $5,340, or $60 per airplane.

The cost impact figures discussed above are 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 conversion of the configuration of the airplane that is specified in this AD action as an option for Diamond I airplanes, if accomplished, will require actions related to the airframe and the engine. The airframe portion of the conversion will take approximately 160 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts will cost approximately $50,000 per airplane. The engine portion of the conversion should be accomplished during a regular engine overhaul; therefore, it will require no additional work hours. Required parts for this action will cost approximately $260,000 per airplane. Based on these figures, the cost impact of the conversion on U.S. operators, who elect to accomplish it, is estimated to be $319,600 per airplane.

If accomplished, the option for modification of the warning horn system that is specified in this AD action for Diamond I airplanes will take approximately 6 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts will cost approximately $600 per airplane. Based on these figures, the cost impact of the proposed modification on U.S. operators will be $960 perairplane.

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 final evaluation has been prepared for this action and it is contained in the Rules Docket. A copyof 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 adding the following new airworthiness directive: