Copy · Textron Mandatory Service Letter MTL-57-04 Rev 1 · 8 pages

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Beechcraft SER VICE LETTER MANDA T OR Y MTL - 57 - 04

REVISION

TRANSMITT AL This sheet transmits Revision 1 to MTL - 57 - 04 , which:

A.

Corrected reference in the References Section.

NOTE:

This revision replaces the original issue of MTL - 57 -

04.

REVISION

COMPLIANCE NO EFFECT .

Airplanes previously modified by this service letter are not af fected.

LOG OF

REVISIONS Original Issue February 21 , 2025 Revision 1 March 27 , 2025 Original Issue - February 21 , 2025 MTL - 57 - 04 Revision 1 - March 27 , 2025 Page 1 of 1 T extron A viation Customer Service , P .O.

Box 7706 , Wichita , KS 67277 , U.S.A.

1 - 316 - 517 - 5800

COPYRIGHT © 2025

No text on this page: it may be a figure. Open the PDF to see it.

Beechcraft SER VICE LETTER MANDA T OR Y MTL - 57 - 04 TITLE WINGS - CRACK

INSPECTION - WING A TT ACH

FITTINGS AND

OUTBOARD WING SP AR CAPS FOR HEA

VYWEIGHT MODEL B300 / B300C

EFFECTIVITY NOTE:

Any aircraft identified in the Serial Ef fectivity below that is operating with a Special Inspection Supplement should contact your Field Service Representative or T eam T urboprop for further guidance.

NOTE:

Also af fected are any Model B300 or B300C serials that have the following Field Kits installed.

• Kit 130 - 4402 T op Kit Heavy W eight B300 , Ef fective:

FL - 91 , FL - 387 , FL - 391 , FL - 381 , FL383 , FL - 387 , FL - 391 and On

• Kit 130 - 4030 Kit T op – Heavy W eight B300 / B300C Non - ER , Ef fective for FL - 381 , FL - 383 and On , and FM - 12 and On

• Kit 130 - 4014 Increased Gross W eight B300 W Extended Range Fuel T ank , Ef fective for FL - 1 and On , and FM - 1 and On MODEL SERIAL

NUMBERS B300 FL - 594 , FL - 599 , FL - 623 thru FL - 626 , FL - 628 , FL - 635 , FL - 637 , FL - 639 , FL - 640 thru FL - 642 , FL - 644 , FL - 646 thru FL - 649 , FL - 654 thru FL - 656 , FL - 659 thru FL - 663 , FL - 667 , FL - 674 , FL - 676 , FL - 678 , FL - 679 , FL - 681 , FL - 682 , FL - 684 thru FL - 686 , FL - 695 , FL - 696 , FL - 704 , FL - 708 , FL - 709 , FL - 716 , FL - 717 , FL - 719 , FL - 731 , FL - 734 , FL - 736 thru FL - 739 , FL - 742 , FL - 746 , FL - 751 , FL - 752 , FL - 759 , FL - 765 thru FL - 769 , FL - 770 , FL - 775 thru FL - 777 , FL - 780 , FL - 781 , FL - 791 , FL - 792 , FL - 795 thru FL - 797 , FL - 799 , FL - 800 , FL - 802 , FL - 804 , FL - 832 , FL - 834 , FL - 864 , FL - 870 , FL - 877 , FL - 883 , FL - 855 , FL - 888 , FL - 918 , FL - 922 , FL - 924 , FL - 934 , FL - 942 , FL - 946 , FL - 950 , FL - 951 , FL - 956 thru FL - 958 , FL - 990 , FL - 993 , FL - 994 , FL - 996 , FL - 997 , FL - 1007 , FL - 1009 , FL - 1014 , FL - 1018 , FL - 1030 , FL - 1037 , FL - 1046 , FL - 1058 , FL - 1080 , FL - 1083 , FL - 1 101 , FL - 1 108 , FL - 1 1 12 , FL - 1 1 14 , FL - 1 1 18 , FL - 1 120 , FL - 1 137 , FL - 1 157 , FL - 1 164 , FL - 1 167 , FL - 1 185 , FL - 1 190 thru FL - 1 193 , FL - 1 198 , FL - 1208 , FL - 1213 , FL - 1218 , FL - 1221 , FL - 1225 , FL - 1228 , FL - 1232 , FL - 1233 , FL - 1240 , FL - 1245 , FL - 1249 , FL - 1253 , FL - 1257 , FL - 1258 , FL - 1262 , FL - 1265 , FL - 1274 , FL - 1284 , FL - 1286 , FL - 1291 , FL - 1293 , FL - 1305 , FL - 1310 , FL - 1317 , FL - 1319 , FL - 1322 , FL - 1323 , FL - 1327 , FL - 1329 , FL - 1331 , FL - 1332 , FL - 1341 , FL - 1343 , FL - 1344 Original Issue - February 21 , 2025 MTL - 57 - 04 Revision 1 - March 27 , 2025 Page 1 of 3 T extron A viation Customer Service , P .O.

Box 7706 , Wichita , KS 67277 , U.S.A.

1 - 316 - 517 - 5800 This document contains technical data and is subject to U.S.

export regulations.

This information has been exported from the United States in accordance with export administration regulations.

Diversion contrary to U.S.

law is prohibited.

ECCN:

9E991

COPYRIGHT © 2025

MTL - 57 - 04 Page 2 Revision 1 - March 27 , 2025 Beechcraft SER VICE LETTER MANDA T OR Y MTL - 57 - 04 B300C FM - 21 , FM - 27 , FM - 28 , FM - 30 thru FM - 32 , FM - 34 , FM - 36 thru FM - 41 , FM - 43 , FM - 51 thru FM - 53 , FM - 56 , FM - 57 , FM - 59 , FM - 61 thru FM - 79 , FM - 81 , FM - 82 , FM - 84 thru FM - 86 , FM - 88 , FM - 90 thru FM - 92 , FM - 94 , FM - 96 thru FM - 1 19 REASON The Beechcraft Structural Inspection and Repair Manual (SIRM) has a new revision.

This revision separated the inspection criteria and intervals between the 15 , 000 lb Max T ake Of f W eight (MT OW) airplanes and the 16 , 500 lb MT OW airplanes.

DESCRIPTION This service document provides information about the new and updated inspection criteria within the structural inspection and repair manual , based upon the airplane operating hours.

COMPLIANCE MANDA T OR Y .

This service document must be accomplished by aircraft that either have or are operating at a 16 , 500 lb MT OW as follows:

W ith Flight Hours Of Flight - Hours T o Comply W ith Initial Inspection 0 - 3 , 800 within 100 hours upon reaching 3 , 800 hours 3 , 801 - 7400 within 200 hours or 6 months 7401 and On Contact T eam T urboprop Immediately NOTE:

Kit 101 - 4077 must be installed at 7400 hours.

NOTE:

Aircraft which have had a wing evaluation performed by T extron A viation (T A) Special Missions and issued serial number specific Airworthiness Limitations Manual (ALM) and Structural Inspection and Repair Manual (SIRM) supplements should continue to use those supplements and no action is required.

A service document published by T extron A viation may be recorded as completed in an aircraft log only when the following requirements are satisfied:

1) The mechanic must complete all of the instructions in the service document , including the intent therein.

2) The mechanic must correctly use and install all applicable parts supplied with the service document kit.

Only with written authorization from T extron A viation can substitute parts or rebuilt parts be used to replace new parts.

3) The mechanic or airplane owner must use the technical data in the service document only as approved and published.

4) The mechanic or airplane owner must apply the information in the service document only to aircraft serial numbers identified in the Effectivity section of the document.

5) The mechanic or airplane owner must use maintenance practices that are identified as acceptable standard practices in the aviation industry and governmental regulations.

No individual or corporate organization other than T extron A viation is authorized to make or apply any changes to a T extron A viation - issued service document or flight manual supplement without prior written consent from T extron A viation.

T extron A viation is not responsible for the quality of maintenance performed to comply with this document , unless the maintenance is accomplished at a T extron A viation - owned Service Center .

CONSUMABLE MA TERIAL No specialized consumable materials are required to complete this service document.

Beechcraft SER VICE LETTER MANDA T OR Y MTL - 57 - 04 T OOLING No specialized tooling is required to complete this service document.

REFERENCES Beechcraft Structural Inspection and Repair Manual , Chapter 57 , Crack Inspection - Wing Attach Fittings and Outboard Wing Spar Caps (Model B300 / B300C).

(Revision D6 and later .)

Beechcraft Model B300 / B300C Airworthiness Limitations Manual , Chapter 4 , Airworthiness Limitations , (4 - 00 -

00) , Revision F1 and later .

PUBLICA TIONS

AFFECTED None

ACCOMPLISHMENT

INSTRUCTIONS

1.

Depending upon the aircraft operating hours go to the steps that follows:

• Refer to the Beechcraft King Air Series Structural Repair Manual , Chapter 57 , Crack Inspection - Wing Attach Fittings and Outboard Wing Spar Caps (Model B300 / B300C) , Revision D6 and later .

NOTE:

Aircraft which have had a wing evaluation performed by T A Special Missions and issued serial number specific ALM and SIRM supplements should continue to use those supplements and no action is required.

A.

Airplanes that have or are operating at a 16 , 500 lb MT OW and with 0 to 3 , 800 hours needs to transition to the new SIRM revision for 16 , 500 lb MT OW airplane at 3 , 800 hours.

B.

Airplanes that have or are operating at a 16 , 500 lb MT OW with 3 , 801 hours to 7 , 400 hours needs to transition to the new SIRM revision for 16 , 500 lb MT OW aircraft within 200 hours or 6 months.

C.

Airplanes that have or are operating at a 16 , 500 lb MT OW with 7 , 401 and On hours , contact T eam T urboprop at teamturboprop@txtav .com or 316 - 517 - 9355.

2.

Remove the maintenance warning tags and connect the airplane battery .

3.

Make an entry in the airplane logbook that states compliance and method of compliance with this service document.

NOTE:

T extron A viation recommends that compliance with all service documents is reported to a maintenance tracking system provider .

• Complete a record of compliance.

(Maintenance T ransaction Report , Log Book Entry , or other record of compliance.)

• Put a copy of the completed record of compliance in the airplane logbook.

• Send a copy of the completed record of compliance to the maintenance tracking system provider used.

MA TERIAL

INFORMA TION No parts are required to complete this service document.

MTL - 57 - 04 Revision 1 - March 27 , 2025 Page 3

No text on this page: it may be a figure. Open the PDF to see it.

Beechcraft OWNER

ADVISOR Y MTL - 57 - 04 TITLE WINGS - CRACK

INSPECTION - WING A TT ACH

FITTINGS AND

OUTBOARD WING SP AR CAPS FOR HEA

VYWEIGHT MODEL B300 / B300C T O:

Beechcraft Model B300 and B300C Aircraft Owner REASON The Beechcraft Structural Inspection and Repair Manual (SIRM) has a new revision.

This revision separated the inspection criteria and intervals between the 15 , 000 lb Max T ake Of f W eight (MT OW) airplanes and the 16 , 500 lb MT OW airplanes.

Also af fected are any Model B300 or B300C serials that have the following Field Kits installed.

• Kit 130 - 4402 T op Kit Heavy W eight B300 , Ef fective:

FL - 91 , FL - 387 , FL - 391 , FL - 381 , FL383 , FL - 387 , FL - 391 and On

• Kit 130 - 4030 Kit T op – Heavy W eight B300 / B300C Non - ER , Ef fective for FL - 381 , FL - 383 and On , and FM - 12 and On

• Kit 130 - 4014 Increased Gross W eight B300 W Extended Range Fuel T ank , Ef fective for FL - 1 and On , and FM - 1 and On

COMPLIANCE MANDA T OR Y .

This service document must be accomplished by airplanes that either have or are operating at a 16 , 500 lb MT OW as follows:

W ith Flight Hours Of Flight - Hours T o Comply W ith Initial Inspection 0 - 3 , 800 within 100 hours upon reaching 3 , 800 hours 3 , 801 - 7400 within 200 hours or 6 months 7401 and On Contact T eam T urboprop Immediately NOTE:

Kit 101 - 4077 must be installed at 7400 hours.

NOTE:

Aircraft which have had a wing evaluation performed by T extron A viation Special Missions and issued serial number specific Airworthiness Limitations Manual and Structural Inspection and Repair Manual supplements should continue to use those supplements and no action is required.

LABOR HOURS WORK PHASE LABOR - HOURS Modification As Required T est and Inspection As Required MA TERIAL A V

AILABILITY No parts are required to complete this service document.

W

ARRANTY This service document is mandatory .

Eligible airplanes may qualify for parts and labor coverage to the extent noted in the Labor Hours and Material A vailability sections of this document.

MTL - 57 - 04 February 21 , 2025 Page 1 of 2 T extron A viation Customer Service , P .O.

Box 7706 , Wichita , KS 67277 , U.S.A.

1 - 316 - 517 - 5800 This document contains technical data and is subject to U.S.

export regulations.

This information has been exported from the United States in accordance with export administration regulations.

Diversion contrary to U.S.

law is prohibited.

ECCN:

9E991

COPYRIGHT © 2025

MTL - 57 - 04 Page 2 February 21 , 2025 Beechcraft OWNER

ADVISOR Y MTL - 57 - 04 Eligibility:

Airplanes identified within the serial number ef fectivity of this service document must have active Airframe warranty coverage on the original issue date of this document and the coverage must be active on the day the work is accomplished.

Parts Coverage:

T extron A viation - owned and T extron A viation - authorized Service Facilities , operators , or other maintenance facilities may submit a claim for the parts required to accomplish this service document as defined in the Material A vailability section of this document.

Labor Coverage:

T extron A viation - owned and T extron A viation - authorized Service Facilities rated to perform maintenance on the specific model of Beechcraft Aircraft may submit a claim for the labor necessary to accomplish this service document as defined in the Labor Hours section of this document.

Credit Application:

After this service document has been accomplished , a claim must be submitted to T extron A viation within 30 days of the service document completion.

Claims for compliance of this service document are to be filed as a W4 type claim.

Please submit your claim form online at ww2.txtav .com / Parts or email the completed T extron A viation Claim Form to warranty@txtav .com .

If submitted on - line a Return Authorization will be provided.

If a paper claim is submitted your claim will be entered into the system and a Return Authorization will be sent to you.

The Return Authorization must accompany any required return parts (see Material A vailability ) , to the point of purchase.

Parts to be returned to T extron A viation should be forwarded to:

TEXTRON A VIA TION P AR TS

DISTRIBUTION W

ARRANTY

ADMINISTRA TION BLDG P43 DOCK R5 7123 SW BL VD Expiration:

February 21 , 2027 (after this date the owner / operator assumes the responsibility for compliance costs) T extron A viation reserves the right to void continued airplane warranty coverage for the parts af fected by this service document until the service document is accomplished.

NOTE:

As a convenience , service documents are now available online to all our customers through a simple , free - of - charge registration process.

If you would like to sign up , please visit the Customer Access link at support.txtav .com to register .