# STC SE03036CH - Type: Supplemental type certificate - Status: Current, Issued - Holder: Delta Air Lines Inc., United States - Description: Application of a deep compressive stress layer using a Low Plasticity Burnishing (LPB) process on CFM56-7 Series Engines Stage 1 High Pressure Compressor (HPC) Blade Dovetails in accordance with Delta Air Lines Inc. Drawing No. 72-0396, Revision B, dated November 3, 2011, or later FAA Approved revision. - Applied: November 24, 2010 - Status date: December 14, 2011 - Product: Aircraft - Certification basis: Part 21, Part 33 - Data sheets: [TCDS E00055EN](https://openairdocs.org/tcds/E00055EN) - Certificate PDF: https://openairdocs.org/files/sha256/65/e7/65e7d167005c581644e19da895735eec77cac0b70afebb2bf60e29f3121bed82 - Approved model list and other attachments: [STC SE03036CH AML.pdf](https://openairdocs.org/files/sha256/be/26/be26cc01dcb89bf9077e54237ada518edcca59982562dddd7ffe0678f8ac5ec5) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/55A6D66A664F60CD86257981006846D3.0001 - DRS record last changed: December 6, 2025 - Page: https://openairdocs.org/stc/SE03036CH ## ADs that name it (0) None. ## Approved models (30) - CFM International S.A. CFM56-7B20 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B20/2 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B20/3 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B22 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B22/2 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B22/3 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B22/3B1 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B22/B1 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B24 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B24/2 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B24/3 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B24/3B1 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B24/B1 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B26 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B26/2 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B26/3 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B26/3B1 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B26/3B2 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B26/3B2F ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B26/3F ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B26/B1 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B26/B2 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B27 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B27/2 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B27/3 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B27/3B1 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B27/3B3 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B27/3F ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B27/B1 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) - CFM International S.A. CFM56-7B27/B3 ([TCDS E00055EN](https://openairdocs.org/tcds/E00055EN)) ## What the certificate says Read from the PDF's text layer, without the form's printed wording; the layout is lost and the order can differ. The PDF is the record. Part 33 of the Code of Federal Regulations See Type Certificate Data Sheet. Nos. E00055EN or E00056EN for complete certification basis. Application of a deep compressive stress layer using a Low Plasticity Burnishing (LPB) process on CFM56-7 Series Engines Stage 1 High Pressure Compresso r (HPC) Blade Dovetails in accordance with Delta Air Lines Inc. Drawing No. 72-0396, Revision B, dated November 3, 2011, or later FAA Approved revision. 1. Compatibility of this design change with previously approved modifications must be determined by the installer. 2. The 1st Stage HPC blades modified in accordance with this STC can only be installed in engine models specifically listed in the attached AML. 3. Any weld repairs or thermal heat treatments exceeding 600 degrees F require the LPB process to be re-applied. 4. The 1st Stage HPC blades, part numbers P331P01, P331P02, P331P03, P331P04, P 331P06, & P331P07 modified by STC SE03036CH cannot be intermixed with P391P02, P391P05 & P391P06 part number blades. 5. A facility that performs the LPB process in accordance with this STC must be FAA Approved. 6. Delta Air Lines, Inc. Instructions for Continued Airworth iness (ICA), for HPC blades modified in accordance with STC SE03036CH, FAA Accepted on December 14, 2011, or later FAA Accepted revision is required. 7. If the holder agrees to permit another pers on to use this certificate to alter the product, the holder shall give the other person written evidence of that permission. ...End... This certificate and the supporting data, which is the basis for approva l, shall remain in effect until surrendered, suspended, revoked or a termination date is otherwise established by the Administrator of the Federal Aviation Administration. Delta Air Lines Inc. 1775 Aviation Blvd Atlanta, GA 30320-6001 E00055EN, E00056EN CFM International, S.A. Make : Model : See AML Date reissued : Original Signed By: Timothy Smyth (Signature) Timothy Smyth Manager, Propulsion Branch Chicago Aircraft Certification Office (Title) Date of application: November 24, 2010 Date of issuance: December 14, 2011 Limitations and Conditions (Continued) ### STC SE03036CH AML.pdf 1 FAA Approved Model List (AML) No. SE03036CH Delta Air Lines, Inc. For Application of Low Plasticity Burnishing on CFM56-7 Series Engines Stage 1 High Pressure Compressor (HPC) Blade Dovetails Issue Date: December 14, 2011 Page 1 of 2 Application Instructions Item Engine Make Engine Model Original Type Certificate Number Certification Basis For Alteration Number Revision & Date AML Amendment Date Stage 1 HPC Blade CFM International S.A. CFM56-7B20 CFM56-7B20/2 CFM56-7B20/3 CFM56-7B22 CFM56-7B22/2 CFM56-7B22/3 CFM56-7B22/3B1 CFM56-7B22/B1 CFM56-7B24 CFM56-7B24/2 CFM56-7B24/3 CFM56-7B24/3B1 CFM56-7B24/B1 CFM56-7B26 CFM56-7B26/2 CFM56-7B26/3 CFM56-7B26/3B1 CFM56-7B26/3B2 CFM56-7B26/3B2F CFM56-7B26/3F CFM56-7B26/B1 CFM56-7B26/B2 CFM56-7B27 E00055EN E00056EN 14 Code of Federal Regulations (CFR) Part 33 Drawing No. 72-0396 Rev. B Dated November 3, 2011, or later FAA Approved Revision Original Application Instructions Item Engine Make Engine Model Original Type Certificate Number Certification Basis For Alteration Number Revision and Date AML Amendment Date Stage 1 HPC Blade CFM International S.A. CFM56-7B27/2 CFM56-7B27/3 CFM56-7B27/3B1 CFM56-7B27/3B1F CFM56-7B27/3B3 CFM56-7B27/3F CFM56-7B27/B1 CFM56-7B27/B3 E00055EN E00056EN 14 Code of Federal Regulations (CFR) Part 33 Drawing No. 72-0396 Rev. B Dated November 3, 2011, or later FAA Approved Revision Original FAA Approved: __ Original Signed By: Timothy Smyth ________________________ T i m o t h y S m y t h Manager, Propulsion Branch Chicago Aircraft Certification Office ## Every issue (1) - December 14, 2011: Issued, Current. [certificate](https://openairdocs.org/files/sha256/65/e7/65e7d167005c581644e19da895735eec77cac0b70afebb2bf60e29f3121bed82), [STC SE03036CH AML.pdf](https://openairdocs.org/files/sha256/be/26/be26cc01dcb89bf9077e54237ada518edcca59982562dddd7ffe0678f8ac5ec5) --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.