# Tecnam Service Bulletin 937-CS: No revision named - Rights: © Tecnam. Filed by the FAA in regulations.gov docket FAA-2026-2728; AD 2026-07-05 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [Tecnam Service Bulletin 937-CS](https://openairdocs.org/service-documents/tecnam/937-cs.md) - Title as filed: TECNAM Service Bulletin SB 937-CS-Ed 2 Rev 1 - Pages: 4 - PDF: https://openairdocs.org/files/sha256/a4/a3/a4a30da08ffd735d25e045e0d5c8739b9a977871bedc808b489636bd13786018 - Page: https://openairdocs.org/service-documents/tecnam/937-cs/file/a4a30da08ffd ## Text Each page's text from the PDF; open the PDF at a page with #page=N. ### Page 1 SERVICE BULLETIN N° SB 937 – CS – Ed. 2 Rev. 1 Date: 26/02/2026 The technical content of this document is approved under the authority of DOA ref. EASA.21J.335 Approval No: DO-937-250916 Page 1/4 MOD. PD-006-03 rev.3 data: 04/03/20 SERVICE BULLETIN Edition 2 Rev. 1 MANDATORY by the AD No. 2026-0023   May become MANDATORY after EASA evaluation  RECOMMENDED ………………………….    INFORMATION ………………………………………… SUBJECT: P2010 Lycoming IO-390 – Exhaust Muffler Flame Tube In- spection SCOPE: Following an occurrence report involving a Tecnam P2010 aircraft equipped with a Lycoming IO-390 engine, Tecnam has identified a potential risk concerning the structural integ- rity of the flame tube located within the exhaust muffler. If not addressed, this condition could result in a partial or complete obstruction of the exhaust system, potentially lead- ing to engine malfunction or stoppage. Therefore, Tecnam mandates a dedicated repetitive inspec- tion of the affected area of th e exhaust muffler (refer to Ap- pendix A for instructions). APPLICABILITY: All P2010 aircraft equipped with the Lycoming IO-390 en- gine (MOD2010/078), up to S/N 335 (inclusive) TIME OF COMPLIANCE:  Initial inspection within: A or B, whichever occurs later A Before exceeding 200 fli ght hours (FH) total time since new (TTSN) B 25 FH or 30 days, whichever occurs first after the issue date of this SB  Subsequent inspections (e very 200 FH) to be accom- plished i.a.w. AMM 2010/101 Supplement S6 Ed. 2 Rev. 2 or later revisions. Note: a non-cumulative tolerance of 10 FH/1 month (which- ever occurs first) may be applied to the 200 FH interval for the initial and repetitive inspection to allow synchronization of the required inspection with other maintenance tasks. Aircraft inspected in accordance with previous revisions of this Service Bulletin are considered compliant with the initial inspection requirements of the current Service Bul- letin until the next scheduled inspection becomes due. ### Page 2 SERVICE BULLETIN N° SB 937 – CS – Ed. 2 Rev. 1 Date: 26/02/2026 The technical content of this document is approved under the authority of DOA ref. EASA.21J.335 Approval No: DO-937-250916 Page 2/4 MOD. PD-006-03 rev.3 data: 04/03/20 SERVICE BULLETIN Edition 2 Rev. 1 MANPOWER: 2 man-hours REQUIRED MATERIAL: Nil TOOLING: Standard toolbox and borescope WEIGHT AND BALANCE: Nil REFERENCES: P2010 AMM Supplement S6 - Ed. 2 Rev. 2 or later PUB. AFFECTED: P2010 AMM Supplement S6 For further information please contact TECNAM:  Technical Support: o Email: technical.support@tecnam.com or Tel: 0039 0823 997538  Spare Parts o Email: spareparts@tecnam.com or Tel: 0039 0823 622297 ### Page 3 SERVICE BULLETIN N° SB 937 – CS – Ed. 2 Rev. 1 Date: 26/02/2026 The technical content of this document is approved under the authority of DOA ref. EASA.21J.335 Approval No: DO-937-250916 Page 3/4 MOD. PD-006-03 rev.3 data: 04/03/20 SERVICE BULLETIN Edition 2 Rev. 1 Appendix A N Accomplishment Instructions 1 Set the aircraft in safety conditions (refer to AMM, ATA 10-10-00) 2 Remove the exhaust assembly following the applicable procedure in AMM Supplement S6, ATA 78-10 (Lycoming IO-390) 3 Carry out the inspection of the exhaust flame tube Refer to Figure 1 Perform a detailed borescope inspection of the internal surfaces of the perforated flame tube within the exhaust muffler, accessing the interior through both the left and right en- try points (points 1a and 1b). Focus the inspection on the region adjacent to the steel baf- fle plate located at the mid-length of the flame tube itself (the plate is highlighted in red in the 3D model shown as reference). It is mandatory to perform the inspection from both sides to ensure full coverage. Check for any of the following conditions: cracks, fractures or any signs of potential initiation of such defects. Subsequently, conduct a bo- rescope inspection of the external surfaces of the perforated flame tube by inserting the borescope through the single outlet port normally leading to the exhaust terminal (point 2), checking for the same conditions as above. The external surface of the flame tube shall be inspected along its entire length, with particular attention to the area around the two edges of the steel baffle plate that are welded to the flame tube. 4 If any abnormal condition is found, contact Tecnam for further instructions (an Oc- currence Report will be required) If no damage is found during the inspection, proceed with reinstalling the exhaust muf- fler. Refer to the applicable procedure in AMM Supplement S6, ATA 78-10 5 Record compliance with this Service Bulletin in the aircraft maintenance log ### Page 4 SERVICE BULLETIN N° SB 937 – CS – Ed. 2 Rev. 1 Date: 26/02/2026 The technical content of this document is approved under the authority of DOA ref. EASA.21J.335 Approval No: DO-937-250916 Page 4/4 MOD. PD-006-03 rev.3 data: 04/03/20 SERVICE BULLETIN Edition 2 Rev. 1 Figure 1 - Exhaust Muffler Flame Tube Inspection (3D model for reference only) 1b 1a 2 Baffle plate edges to be checked for potential cracks Perforated flame tube --- 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, except the copies of manufacturers’ service documents, which belong to their rights holders.