August 2026 Technically

August 2026 Technically

FAA Airworthiness Directive 2026-15-05: Wing Structure

Effective date: Aug. 10, 2026

Applicability: This AD applies to Textron Aviation Inc. Model B300 and B300C airplanes, certificated in any category, identified in Textron Mandatory Service Letter MTL-57-04, Revision 1, dated March 27, 2025, including airplanes identified below, except for any airplane that has had a wing evaluation performed by Textron Aviation Special Missions and been issued a serial number specific aircraft limitations manual and structural inspection and repair manual supplements.

(1) Model B300 airplanes (heavy weight) having Kit 130-4402 installed: S/Ns FL-91, FL-381, FL-383, FL-387, FL-391 and on.

(2) Model B300 (heavy weight) and B300C (non-extended range) airplanes having Kit 130-4030 installed: S/Ns FL-381, FL-383 and on, and FM-12 and on.

(3) Model B300 (increased gross weight with extended-range fuel tank) airplanes having Kit 130-4014 installed: S/Ns FL-1 and on and FM-1 and on.

Reason: This AD was prompted by the manufacturer’s revision of the structural inspection and repair manual to introduce more restrictive inspection intervals for airplanes that are certified to or operating at a 16,500 pound maximum takeoff weight (MTOW). The FAA is issuing this AD to prevent undetected cracks in the wing or wing supporting structure. The unsafe condition, if not addressed, could result in reduced structural integrity and consequent wing separation from the fuselage in flight.

Required actions: At the applicable compliance time specified below, revise the Limitations Section of the existing aircraft maintenance manual or instructions for continued airworthiness and the existing maintenance or inspection program, as applicable, by incorporating the information identified in the table below.

(1) For airplanes that are certified to or operating at 16,500 lb. MTOW and with 3,800 hours total time-in-service (TTIS) or less: Before accumulating 3,800 hours TTIS or within 25 hours time-in-service (TIS) or 30 days after the effective date of this AD, whichever occurs later.

(2) For airplanes that are certified to or operating at 16,500 lb. MTOW and with between 3,801 and 7,400 TTIS: Within 200 hours TIS or 6 months, whichever occurs first after the effective date of this AD.

(3) For airplanes that are certified to or operating at 16,500 lb. MTOW and with more than 7,401 hours TTIS: Within 25 hours TIS or 30 days, whichever occurs first after the effective date of this AD.

Task No.

Component

Interval

57-00-00-9602

Wing to Fuselage Attach Angles (FL-1 through FL-175, FL-177; FM-1 through FM-9; unless Kit 101-1202-0001 is installed)

16,500 MTOW airplanes, replace every 2,500 hours.

57-00-00-9603

Wing to Fuselage Attach Angles (FL-176, FL-178 and after; FM-10 and after; and prior airplanes with Kit 101-1202-0001 installed)

16,500 MTOW airplanes, replace every 29,200 hours.

57-20-01-9600

Outboard Wing Structure (FL-1 through FL-125; FM-1 through FM-8; unless 101-110085-1 and -2 spar caps are installed)

16,500 MTOW airplanes, replace every 6,500 hours.

There are no life limitation inspection tasks associated with the wing center section

Wing Center Section (FL-126 and after; FM-9 and after; and prior airplanes with Kit 101-1200-0001 installed)

The life is not limited provided the inspection programs defined in the listed maintenance manuals and the replacement schedule for the items listed below have been adhered to for continued airworthiness. King Air Series Structural Inspection and Repair Manual, P/N 98-39006, Revision D6. • Chapter 57-18-02 Super King Air Model B300/B300C Maintenance Manual, P/N 130-590031-11. • Chapter 5 • Chapter 57 Super King Air Model B300/B300C Fusion Maintenance Manual, P/N 434-590169-0009. • Chapter 5 • Chapter 57

There are no life limitation inspection tasks associated with the outboard wing structure.

Outboard Wing Structure (FL-126 and after; FM-9 and after; and prior airplanes with 101-110085-1 and -2 spar caps installed)

The life is not limited provided the inspection programs defined in the listed maintenance manuals and the replacement schedule for the items listed below have been adhered to for continued airworthiness. King Air Series Structural Inspection and Repair Manual, P/N 98-39006, Revision D6. • Chapter 57-18-02 Super King Air Model B300/B300C Maintenance Manual, P/N 130-590031-11. • Chapter 5 • Chapter 57 Super King Air Model B300/B300C Fusion Maintenance Manual, P/N 434-590169-0009. • Chapter 5 • Chapter 57

For further information contact: Soban Saeed, Aviation Safety Engineer, FAA, 1801 S. Airport Road, Wichita, KS 67209; phone: 316-946-4123; email: CCB-COS@faa.gov.

The above information is abbreviated for space purposes. For the entire communication, go to faa.gov/regulations_policies/airworthiness_directives.

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