SAIB CE-03-49 —

1 SPECIAL AIRWORTHINESS INFORMATION BULLETIN

Aircraft Certification Service Washington, DC

U.S. Department of Transportation Federal Aviation Administration

No. CE-03-49 August 13, 2003 We post SAIBs on the internet at www.airweb.faa.gov This is information only. Recommendations are not mandatory.

Introduction This Special Airworthiness Information Bulletin (SAIB) alerts you, a registered owner or operator of Mitsubishi Heavy Industries (MHI) manufactured aircraft MU-2B/-10/-15/-20/-25/-26: (S/N 008 through 347, except S/N 313, 321), and MU-2B-30/-35/-36: (S/N 501 through 696 except 652, 661) of the release of MHI Service Bulletins Number 230, dated March 5, 1997 and Number 219A, dated October 24, 1994 and MU-2B-25/-26/-26A/-40: (S/N 313SA, 321SA, 348SA through 459SA) and MU-2B-35/-36/-36A/-60: (S/N 652SA, 661SA, 697SA through 1569SA) of the release of MHI Service Bulletins Number 092/32-015, dated April 28, 1997 and Number 082/32-012, dated August 24, 1993. These Service Bulletins address the Modification of Bearing Box - Landing Gear Actuating Mechanism and the Emergency Gear Down Gearbox Lower Pin Replacement for the Japanese Civil Airworthiness Bureau (JCAB) and The FAA certified aircraft respectively.

Background The (JCAB), which is the airworthiness authority for Japan, notified the FAA of two separate unsafe conditions that may exist on certain Mitsubishi MU-2B series airplanes.

The JCAB reports that a bearing in the landing gear power train separated from the housing that resulted in a landing with partially extended landing gear. A separate condition was found during maintenance in which the lower pin of an emergency geardown gearbox had fallen out of the bracket housing and was found on the lower skin in the fuselage. Loss of this pin may cause interference with emergency gear down operations.

The above service bulletins, 230 and 092/32-015, provide you with instructions for installing bearing retention brackets on each bearing box in the landing gear power train, to inspect the spline for cracks, to inspect the bearing box to determine if the bearing has shifted, and to replace any cracked spline or any bearing box where the bearing has shifted.

The service bulletins 082/32-012 and 219A provide instructions for replacement of the emergency gear down gearbox lower pin with a bolt assembly. These services bulletins require, for the affected airplanes that are equipped with a certain emergency geardown gearbox, an inspection of the lower pin hole and surrounding boss area for cracks, and replacement of the emergency geardown gear box if any crack(s) is found.

The JCAB has issued an Airworthiness Directive (AD) for the implementation of the service bulletins for Japan.

2 The above Service Bulletins are intended to prevent the inability to completely extend the landing gear caused by the separation of a bearing in the landing gear power train from the housing and to prevent interference with emergency gear down operations caused by the lower pin of the emergency down gear box falling out. If not prevented, either of these conditions could result in reduced or loss of control of the airplane during landing operations.

Recommendation The service bulletins identified in this document are not considered appropriate for AD action at this time. However, we strongly recommend all owners and operators of the Mitsubishi MU-2B series aircraft listed above review their compliance with the following applicable service bulletins and if not complied with to implement compliance at your earliest convenience.

Mitsubishi Airplane Series Service Bulletin Number/Date Model/Serial Number Title 219A dated Oct. 24, 1994 MU-2B/-10/-15/-20/-25/-26: S/N 008 thru 347 (except S/N 313, 321) MU-2B-30/-35/-36: S/N 501 thru 696 (except 652, 661) “Emergency Gear Down Gearbox Lower Pin Replacement.” 230 dated March 5, 1997 MU-2B/-10/-15/-20/-25/-26: S/N 008 thru 347 (except S/N 313, 321) MU-2B-30/-35/-36: S/N 501 thru 696 (except 652, 661) “Modification of Bearing Box – Landing Gear Actuating Mechanism” 082/32-012, dated August 24, 1993 MU-2B-25/-26/-26A/-40: S/N 313SA, 321SA, 348SA thru 459SA MU-2B-35/-36/-36A/-60: S/N 652SA, 661SA, 697SA thru 1569SA “Emergency Gear Down Gearbox Lower Pin Replacement” 092/32-015 dated April 28, 1997 MU-2B-25/-26/-26A/-40: S/N 313SA, 321SA, 348SA thru 459SA MU-2B-35/-36/-36A/-60: S/N 652SA, 661SA, 697SA thru 1569SA “Modification of Bearing Box – Landing Gear Actuating Mechanism”

This Service Bulletin Can Be Obtained From Mitsubishi Heavy Industries America, Inc., Aircraft Product Support Division, 4951 Airport Parkway, Ste. 800, Addison, Texas 75001; phone (972) 934-5480; fax: (972) 934-5488.

For Further Information, Contact For airplanes covered under Service Bulletin 230 or 219A: Mr. Carl Fountain, Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, 3960 Paramount Boulevard, Lakewood, California, 90712; phone: (562) 627-5222; fax: (562) 627-5210; email: [email protected]

For airplanes covered under Service Bulletin 082/32-012 or 092/32-015 : Mr. Werner Koch, Aerospace Engineer, FAA, Airplane Certification Office, ASW-150, 2601 Meacham Blvd., Fort Worth, Texas 76193-0150; phone: (817) 222-5133; fax: (817) 222-5960; email: [email protected]