# SAIB NE-20-05: POWERPLANT - Engine Camshaft Gear Tooth Fracture - Type: Special airworthiness information bulletin (advisory, not mandatory) - Status: Current - Revision: 0 - Issued: April 6, 2020 - Products: Continental Motors LTSIO-520-AE, TSIO-520-A, TSIO-520-AE, TSIO-520-AF, TSIO-520-B, TSIO-520-BB, TSIO-520-BE, TSIO-520-C, TSIO-520-CE, TSIO-520-D, TSIO-520-DB, TSIO-520-E and 92 more - Product type: Engine - PDF: https://openairdocs.org/files/sha256/62/65/626551ccb04a723303c15b090a593136bbcabac7f3a815b1a47fc95f7053bdd7 - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0A3DC9753AF674E286258542007011D4.0001 - DRS record last changed: April 6, 2020 - Page: https://openairdocs.org/saib/NE-20-05 ## Text FAA Aviation Safety **SPECIAL AIRWORTHINESS** INFORMATION BULLETIN SUBJ: POWERPLANT – Engine Camshaft Gear Tooth Fracture SAIB: NE-20-05 Date: April 6, 2020 This is information only. Recommendations aren’t mandatory. Introduction This Special Airworthiness Information Bulletin (SAIB) alerts registered owners, operators, and certified repair facilities of all airplanes equipped with Continental Aerospace Technologies, Inc. O-470-U, IO-470, IO-520, L/TSIO-520, LIO-520, IO-550, IOF-550, TSIO-550, and TSIOL-550 series reciprocating aviation gasoline (AvGas) engines of possible fatigue failure of camshaft gear teeth resulting in loss of engine power in -flight and forced landings, and of available service instructions that introduce improved camshaft gear, part number (P/N) 656818. The service instructions also provide inspection, removal, and installation procedures for replacing superseded camshaft gear, P/N’s 631845, 655430, 655516 and 656031, with P/N 656818. At this time, the airworthiness concern is not an unsafe condition that would warrant airworthiness directive (AD) action under Title 14 of the Code of Federal Regulations (14 CFR) part 39. Background This SAIB was prompted by reports of fractured camshaft gear teeth, which resulted in the loss of engine power in flight and forced landings. Continental performed a metallurgical analysis of an exemplar camshaft gear, P/N 655516, and the results indicated evidence of fatigue cracking initiating at the surface of the gear tooth root. The cause of fatigue crack initiation is not known. The gear met hardness requirements, and no material anomalies were identified. These findings are consistent with findings from the metallurgical analysis of other camshaft gear failures. Continental introduced camshaft gear, P/N 656818, with an increased thickness as a product improvement in Continental Service Bulletin SB05-8, initial release, dated August 9, 2005, and recommended its installation at the next engine overhaul o r whenever camshaft gear replacement was required. Continental also specified a repair for Permold crankcases with its installation to eliminate potential interference with the new, thicker camshaft gear. Continental subsequently recommended replacement o f camshaft gear P/N’s 631845, 655430, 655516 and 656031 with P/N 656818 at engine overhaul in Continental SB97- 6B, dated November 18, 2009. This information has been incorporated into the Instruction for Continued Airworthiness, Continental Standard Practice Maintenance Manual M-0. With the publication of Continental Critical Service Bulletin CSB05 -8D, dated August 22, 2018, Continental specified a 100-hour or annual inspection, depending on airplane operation or inspection program, or at the next maintenance event when the camshaft gear is accessible, whichever occurs first, for camshaft gear P/N’s 631845, 655430, 655516 and 656031 on the affected engine models. The recurring inspections, for physical damage, fractures or cracks on all visible camshaft gea r surfaces, continue until the aforementioned camshaft gears are replaced with P/N 656818, no later than the next engine overhaul. There have been no reported failures of camshaft gear, P/N 656818. Recommendations The FAA recommends that repair stations, owners, operators and maintenance personnel perform the inspections of camshaft gear P/Ns 631845, 655430, 655516 and 656031 until installation of the improved superseding camshaft gear P/N 656818, as these inspections and replacement as outlined in Conti nental CSB05-8D, dated August 22, 2018. For Further Information, Contact Boyce (Trey) Jones, Aerospace Engineer, Atlanta ACO, 1701 Columbia Ave., College Park, GA 30337; phone: (404) 474-5535; fax: (404) 474-5606; email: Boyce.Jones@faa.gov For Related Service Information Contact Continental Aerospace Technologies, Inc. Customer Services, 2039 South Broad Street, Mobile, AL 36615; phone: (800) 326-0089 ## Registered aircraft it may concern (OpenAirDocs) Registry models matched by make and model, the same way as ADs, most registered aircraft first. - [Continental O-470 series](https://openairdocs.org/engine/continental-o-470-series): 12,779 registered aircraft (engine model) - [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series): 9,486 registered aircraft (engine model) - [Continental I0-470 series](https://openairdocs.org/engine/continental-i0-470-series): 4,499 registered aircraft (engine model) - [Continental TSIO-520 series](https://openairdocs.org/engine/continental-tsio-520-series): 4,064 registered aircraft (engine model) - [Continental IO-550 series](https://openairdocs.org/engine/continental-io-550-series): 3,077 registered aircraft (engine model) - [Continental TSIO-550-K](https://openairdocs.org/engine/continental-tsio-550-k): 2,799 registered aircraft (engine model) - [Continental IO-550-N](https://openairdocs.org/engine/continental-io-550-n): 2,772 registered aircraft (engine model) - [Continental TSIO-550-C](https://openairdocs.org/engine/continental-tsio-550-c): 480 registered aircraft (engine model) - [Continental TSIO-550 series](https://openairdocs.org/engine/continental-tsio-550-series): 382 registered aircraft (engine model) - [Continental IO-550-B](https://openairdocs.org/engine/continental-io-550-b): 373 registered aircraft (engine model) - [Continental IO-470 series](https://openairdocs.org/engine/continental-io-470-series): 225 registered aircraft (engine model) - [Continental IO-550-C](https://openairdocs.org/engine/continental-io-550-c): 199 registered aircraft (engine model) - [Continental TSIO-550-G](https://openairdocs.org/engine/continental-tsio-550-g): 129 registered aircraft (engine model) - [Continental IO-550-G](https://openairdocs.org/engine/continental-io-550-g): 115 registered aircraft (engine model) - [Continental IO-520-D](https://openairdocs.org/engine/continental-io-520-d): 95 registered aircraft (engine model) - [Continental IO-520-F](https://openairdocs.org/engine/continental-io-520-f): 80 registered aircraft (engine model) - [Continental TSIO-520-M](https://openairdocs.org/engine/continental-tsio-520-m): 60 registered aircraft (engine model) - [Continental O-470-U](https://openairdocs.org/engine/continental-o-470-u): 56 registered aircraft (engine model) - [Continental TSIO-520-NB](https://openairdocs.org/engine/continental-tsio-520-nb): 52 registered aircraft (engine model) - [Lycoming IO-520 series](https://openairdocs.org/engine/lycoming-io-520-series): 49 registered aircraft (engine model) - [TCM Cont TSIO-520 series](https://openairdocs.org/engine/tcm-cont-tsio-520-series): 49 registered aircraft (engine model) - [Continental TSIO-550-E](https://openairdocs.org/engine/continental-tsio-550-e): 46 registered aircraft (engine model) - [Continental IO-520-BB](https://openairdocs.org/engine/continental-io-520-bb): 44 registered aircraft (engine model) - [Continental IO-550-D](https://openairdocs.org/engine/continental-io-550-d): 36 registered aircraft (engine model) - [Continental TSIO-520-UB](https://openairdocs.org/engine/continental-tsio-520-ub): 27 registered aircraft (engine model) - [Continental IO-550-F](https://openairdocs.org/engine/continental-io-550-f): 26 registered aircraft (engine model) - [Continental IO-520-BA](https://openairdocs.org/engine/continental-io-520-ba): 25 registered aircraft (engine model) - [Continental IO-470-L](https://openairdocs.org/engine/continental-io-470-l): 22 registered aircraft (engine model) - [Continental TSIO-520-R](https://openairdocs.org/engine/continental-tsio-520-r): 22 registered aircraft (engine model) - [Continental TSIO-520-WB](https://openairdocs.org/engine/continental-tsio-520-wb): 19 registered aircraft (engine model) - [Continental TSIO-520-C](https://openairdocs.org/engine/continental-tsio-520-c): 17 registered aircraft (engine model) - [Continental IO-520-B](https://openairdocs.org/engine/continental-io-520-b): 16 registered aircraft (engine model) - [Continental IO-470-N](https://openairdocs.org/engine/continental-io-470-n): 12 registered aircraft (engine model) - [Continental TSIO-520-P](https://openairdocs.org/engine/continental-tsio-520-p): 12 registered aircraft (engine model) - [Continental IO-520-L](https://openairdocs.org/engine/continental-io-520-l): 11 registered aircraft (engine model) - [Continental TSIO-520-H](https://openairdocs.org/engine/continental-tsio-520-h): 11 registered aircraft (engine model) - [Continental TSIO-520-N](https://openairdocs.org/engine/continental-tsio-520-n): 11 registered aircraft (engine model) - [Continental TSIO-520-VB](https://openairdocs.org/engine/continental-tsio-520-vb): 11 registered aircraft (engine model) - [TCM IO-550-N](https://openairdocs.org/engine/tcm-io-550-n): 10 registered aircraft (engine model) - [Continental IO-470-F](https://openairdocs.org/engine/continental-io-470-f): 9 registered aircraft (engine model) - [Continental TSIO-520-B](https://openairdocs.org/engine/continental-tsio-520-b): 9 registered aircraft (engine model) - [Continental TSIO-520-BE](https://openairdocs.org/engine/continental-tsio-520-be): 9 registered aircraft (engine model) - [Continental IO-470-VO](https://openairdocs.org/engine/continental-io-470-vo): 8 registered aircraft (engine model) - [Continental IO-520-A](https://openairdocs.org/engine/continental-io-520-a): 8 registered aircraft (engine model) - [Continental IO-520-K](https://openairdocs.org/engine/continental-io-520-k): 8 registered aircraft (engine model) - [Continental IO-520-MB](https://openairdocs.org/engine/continental-io-520-mb): 8 registered aircraft (engine model) - [Continental TSIO-520-AE](https://openairdocs.org/engine/continental-tsio-520-ae): 8 registered aircraft (engine model) - [Continental IO-470-D](https://openairdocs.org/engine/continental-io-470-d): 7 registered aircraft (engine model) - [Continental IO-470-S](https://openairdocs.org/engine/continental-io-470-s): 7 registered aircraft (engine model) - [Continental IO-550-R](https://openairdocs.org/engine/continental-io-550-r): 7 registered aircraft (engine model) All 113: https://openairdocs.org/saib/NE-20-05/models.md --- 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.