# Airworthiness Directives; CFM International, S. A. Turbofan Engines
> **Rule** · Final rule. · Published 2013-07-30 · Effective 2013-09-03 · 78 FR 45842
## Document
- **Document number:** 2013-17296
- **Category:** airworthiness
- **Type:** Rule
- **Action:** Final rule.
- **Citation:** 78 FR 45842
- **Publication date:** 2013-07-30
- **Effective date:** 2013-09-03
- **FAA docket:** Docket No. FAA-2012-1114
## Abstract

We are adopting a new airworthiness directive (AD) for certain CFM International, S. A. (CFM) model CFM56-5 and CFM56-5B series turbofan engines. This AD was prompted by corrosion of the delta-P valve in the hydro-mechanical unit (HMU) fuel control caused by exposure to type TS-1 fuel. This AD requires cleaning, inspection, and repair of affected HMUs. We are issuing this AD to prevent seizure of the HMU, leading to failure of one or more engines and damage to the airplane.

## Source
- [Federal Register document](https://www.federalregister.gov/documents/2013/07/30/2013-17296/airworthiness-directives-cfm-international-s-a-turbofan-engines)
---
*AI Analytics · CC0 1.0*