STC ST12075IB

IMPORT ST12075IB PT21 SOLUTIONS Ltd.

34 BOULEVARD DES ITALIENS 75009 PARIS FRANCE Part 25 Title 14 Code of Federal Regulations T00001SE The Boeing Company 777-300ER Series

1. The installer must determine whether this design change is compatible with previously approved modifications.

(See Limitations and Conditions Continued on Page 3 of 3) 05/15/2025 07/11/2025 John Yoo Manager, International Validation Branch Compliance & Airworthiness Division Aircraft Certification Service 3

1. Installation of interior reconfiguration. Remove existing 6FC/53BC/259YC configuration including some toilets/galleys and converting the aircraft cabin to a 7BC/514YC configuration in accordance with Pt21 Solutions Master Data List Document Number 21008/MDL/001, Issue 2, dated April 7, 2025, or later EASA approved revisions.

(See Description of Type Design Change Continued on Page 3 of 3)

2. Maintenance in accordance with Pt21 Solutions Instructions for Continued Airworthiness Document Number 21008/ICA/001, Issue 4, dated March 17, 2025, or later EASA accepted revision.

3. Operation in accordance with Pt21 Solutions Aircraft Flight Manual Supplement Document Number 21008/AFM/001, Issue 6, dated February 20, 2025, or later EASA approved revision.

2. Aircraft must be operated in accordance with the "Limitations" section of the Aircraft Flight Manual Supplement document listed under the Description of Type Design Change of this STC.

3. Concurrent required modification to install a new non-electrical floor path marking system must be in accordance with FAA STC ST02530NY.

4. If the holder agrees to permit another person to use this certificate to alter a product, the holder must give the other person written evidence of that permission.

5. This STC is applicable to serial numbers 35301 and 34432 for the The Boeing Company 777-300ER Series model.

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