AD 79-16-01

79-16-01 BEECH: Amendment 39-3520. Applies to Models 65 (Military Models L-23F or U-8F) (Serial Numbers L-1 through L-6, LC-1 through LC-180 and LF-7 through LF-76), 65- 80 (Serial Numbers LD-1 through LD-33, LD-35 through LD-45 and LD-47 through LD-150), 65-A80 and 65-A80-8800 (Serial Numbers LD-34, LD-46 and LD-151 through LD-244) and 65- 90 (Serial Numbers LJ-1 through LJ-67) airplanes certificated in all categories.

COMPLIANCE: Required as indicated unless already accomplished.

To detect fatigue cracks that may exist in certain critical components of the wing structure, accomplish the following:

A) On or before September 7, 1979, except in no event is this one-time inspection required sooner than 30 days after the last inspection in accordance with AD 70-25-01 or 70-25- 04, whichever is applicable, inspect the right and left lower forward inboard and outboard wing to center section attach fittings (2 on left side and 2 on right side of the airplane) for cracks using dye penetrant procedures in accordance with the wing attachment fittings inspection instructions in Class I Beechcraft Service Instructions No. 0393-018 Revision I (Models 65, L-23F, U-8F, 65- 80, 65-A80 and 65-A80-8800) or No. 0394-018 (Model 65-90), whichever is applicable.

NOTE: While inspecting the fittings with the wing attachment bolt removed, special attention should be directed towards inspection of the entire counterbore area in the recess of each fitting.

B) Accomplish the dye penetrant inspections required by Paragraph "A" of this AD (1) using only those materials specified in Table I of this AD and, (2) in accordance with application and developing instructions provided by the manufacturer of the material except that the penetrant must remain on the surface for a minimum of 30 minutes before excess penetrant is removed and developer is applied.

C) Within 48 hours after completion of the inspection required by Paragraph "A" of this AD, complete the reporting form included with this AD as Figure I and mail it to the address shown thereon. (Reporting approved by the Office of Management and Budget under OMB No. 04-R0174.)

TABLE I

Manufacturer Penetrant Remover Developer Ardox, Ltd. Ardox 906 Ardox 9PR 551 Ardox 9D6

Magnaflux Corp. SKL-HF SKL-SF Formula B Spot Chek SKC-S Spot Chek SKD-S Spot Chek

Met-L-Chek Co. VP-31 E-59 D-70

Sherwin, Inc. Dubl-Chek DP-40 Dubl-Chek DR-60 Dubl-Chek D-100

Testing Systems, Inc. Flaw Finder DD60B Flaw Finder SD80B Flaw Finder AD70B

Tokushu Toryo Co. PT (Visible) RT DT

Turco Products Dy-Chek #2 Dy-Chek #3 Dy-Chek NAD

Uresco, Inc. P-300A K-410E D-495

D) If fatigue cracks are found during the inspection required by Paragraph "A" of this AD, prior to further flight, replace specified wing and center section components with new production parts in accordance with instructions in Beechcraft ServiceInstructions No. 0393-018 Revision I (Models 65, L-23F, U-8F, 65-80, 65-A80 and 65-A80-8800) or 0394-018 (Model 65- 90) whichever is applicable. If stress corrosion cracks are found during the inspection required by Paragraph "A" of this AD, prior to further flight, replace right and left lower forward outboard wing to center section attach fittings (2 right side and 2 left side) with new fittings in accordance with the above noted Beechcraft Service Instructions.

E) Aircraft may be flown in accordance with Federal Aviation Regulation 21.197 to a location where this AD can be accomplished.

F) Any equivalent method of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA Central Region.

This Amendment becomes effective August 6, 1979.

REPORTING FORM Airplane Model Number___________________ ____ Airplane Serial Number _______________________

Date of inspection required by this AD . Resultsof inspection required by this AD .

Airframe total hours time-in-service .

Total hours time-in-service on fittings inspected:

Left outboard . Left inboard . Right outboard . Right inboard .

Airplane usage: (Check those for which airplane has been used, if known) 1. General service . 2. Executive Transport . 3. Air Taxi service . 4. Tours of gusty areas . 5. Calibration or patrolling of items on ground or water . 6. Weather studies .

Show approximate percentages (%) of airframe total hours time-in-service, if known, for the following:

1. % of flight time accumulated above 10,000 feet MSL .

2. % of flight time accumulated below 10,000 feet MSL .

3. Approximate indicated airspeed: Above 10,000 feet MSL . Below 10,000 feet MSL .

4. Approximate number of flight hours per landing .

Name and telephone number of person who can supply more information about usage of the airplane , phone number .

FIGURE 1

Mailing Address:

Federal Aviation Administration Wichita Engineering and Manufacturing District Office Attention: Airframe Unit Room 238, Terminal Building Mid-Continent Airport Wichita, Kansas 67209