SAIB CE-12-34

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FAA Aviation Safety SPECIAL AIRWORTHINESS INFORMATION BULLETIN SAIB: CE-12-34 SUBJ: Main Landing Gear: Cracking “A” Frame Assemblies Date: June 12, 2012 This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin (SAIB) is intended to inform you, owners, operators and maintenance personnel, of cracking of part number (P/N) 105-810023-75 and P/N 105-810023- 76 main landing gear (MLG) “A” frame assemblies on Hawker Beechcraft Model Series 76 (also referred to as Beechcraft Duchess) airplanes.

At this time, this airworthiness concern has not been determined to be an unsafe condition that would warrant airworthiness directive (AD) action under Title 14 of the Code of Federal Regulations (14 CFR) part 39.

Background

Airworthiness Directive (AD) 91-14-14 was issued to address the development of cracking and subsequent failures in MLG “A” frame assemblies, which could result in the loss of control of an airplane during landing operations. AD 91-14-14 was then superseded by AD 97-06-10 to provide an exemption for airplanes that have “improved” MLG “A” frame assemblies installed. These improved “A” frame assemblies are identified by P/Ns 105-810023-75 and 105-810023-76. AD 97-06-10 also allows the installation of these improved “A” frame assemblies to eliminate the repetitive inspection requirement.

Since the issuance of AD 97-06-10, there have been several reports of cracking (or even complete failure during landing and taxi operations) of P/Ns 105-810023-75 and 105-810023-76. Hawker Beechcraft Corporation and the FAA have been unable to determine whether the cracking is due to fatigue, static overload, or poor maintenance. The data obtained from service difficulty reports has also not been sufficient to determine the exact cause of cracking. It is known that many of these airplanes are used in training operations and can see a high number of landing cycles as compared to those airplanes used in normal operation.

Recommendations

The FAA recommends continuing inspection of the “A” frame assemblies with P/Ns 105-810023-75 and 105-810023-76 even though AD 97-06-10 does not mandate such an inspection. Performing a 100- hour repetitive inspection, at a minimum, is still recommended.

The FAA also recommends submitting reports of cracking or failures of P/Ns 105-810023-75 and 105-810023-76 in order to support the continued operational safety of the Beechcraft Model 76 fleet It is also recommended to provide additional data and any other information pertinent to this issue.

2 A sample reporting form can be found in Attachment 1. Please submit completed report forms to the Wichita Aircraft Certification Office (ACO) at the following address:

or email: [email protected], include the information from the attachment in the email. Please identify MLG: HBC 76, in the subject line if submitted through email.

Under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has approved the information collection contained in this SAIB, and assigned OMB Control Number 2120-0731.

For Further Information Contact

Adam Neubauer, Aviation Safety Engineer, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Wichita, Kansas 67209; phone: (316) 946-4156; fax: (316) 946-4107; e-mail: [email protected].

Wichita ACO 1801 Airport Road, Room 100 Mid-Continent Airport Wichita, KS 67209

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Attachment 1

Beechcraft Model 76 “A” Frame (P/Ns 105-810023-75/-76) Status Report Airplane S/N Airplane hours Part hours (or cycles) Part status (e.g. no cracks, cracked, failed) Date part installed