AD 90-12-07

90-12-07 BEECH: Amendment 39-6612. Docket No. 90-CE-05-AD.

Applicability: Beech 99 Series (all serial numbers) airplanes certificated in any category.

Compliance: Required within the next 12 calendar months after the effective date of this AD, unless already accomplished.

To preclude the loss of wing attachment integrity due to undetected wing-attach bolt stress corrosion accomplish the following:

(a) Replace any existing steel wing-attach bolts and nuts with Inconel wing-attach bolts and nuts in accordance with the instructions in Beech Structural Inspection and Repair Manual, P/N 98-39006, dated December 20, 1984, or revisions thereto through Revision A4, dated May 1, 1987.

(b) Immediately after installation of any new Inconel nut in the lower, forward wing attachment per paragraph (a) of this AD, except those specially marked with Part No. 81790- 1414, visually inspect the nut for cracks in accordance with the instructions in Beech Mandatory Service Bulletin 2248, dated February 1988. Prior to further flight, replace any nut found cracked with a specially marked Part No. 81790-1414 nut per Figure 2 of the above referenced Service Bulletin.

(c) Airplanes may be flown in accordance with FAR 21.197 to a location where this AD can be accomplished.

(d) An alternate method of compliance or adjustment of the compliance time, which provides an equivalent level of safety, may be approved by the Manager, Wichita Aircraft Certification Office, FAA, 1801 Airport Road, Room 100, Wichita, Kansas 67209; Telephone (316) 946-4400.

NOTE: The request should be forwarded through an FAA Maintenance Inspector, who may add comments and then send it to the Manager, Wichita Aircraft Certification Office.

All persons affected by this directive may obtain copies of the documents referred to herein upon request to the Beech Aircraft Corporation, Commercial Service, Department 52, Wichita, Kansas 67201-0085; or may examine these documentsat the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

This amendment (39-6612, AD 90-12-07) becomes effective on July 2, 1990.