CTHIn ForceLegislation
AD/MAKILA/8 - Engine & Fuel Control - Engine Control Unit
Turbomeca Turbine Engines - Makila SerieTurbomeca Turbine Engines - Makila Series
Start here
Get a plain-English read of Turbomeca Turbine Engines - Makila Serie
Turn the raw legal text into a practical explanation grounded in AD/MAKILA/8 - Engine & Fuel Control - Engine Control Unit.
Turbomeca Turbine Engines - Makila Series
| AD/MAKILA/8 | Engine & Fuel Control - Engine Control Unit | 7/2006 |
|---|
| Applicability: | Makila 1A and 1A1 turbo-shaft engines post modifications TU190, TU202 or TU219, which are installed on AS 332 helicopters. |
|---|---|
| Requirement: | Incorporate modification TU 241 by replacing the Anticipator or Pitch/Gas Link LPG board of the Engine Control Unit (ECU) in accordance with Turbomeca Mandatory Service Bulletin no. 298 73 0241. |
| Note: EASA AD 2006-0070 refers. | |
| Compliance: | Before 31 January 2007. |
| This Airworthiness Directive becomes effective on 6 July 2006. | |
| Background: | The control system of Makila 1A and 1A1 engines post modifications TU190, TU202 or TU219 includes an electrical back-up mode at 85% N1 (gas generator speed) activated on the detection of certain occurrences affecting engine control.The activation of the back-up mode is irreversible and freezes the engine at 85% N1.An analysis of reported in service occurrences showed that the back-up mode can be activated by an electrostatic discharge or by a malfunction of the collective pitch signal. The two engines fitted on the same helicopter can therefore be frozen in this back-up position at 85% N1.This Directive requires the incorporation of modification TU241 on the LPG board of the Makila 1A and 1A1 ECU, which reduces the risk by changing the conditions in which the engines switch to, and are maintained, in the 85% NG back-up mode. |
Image unavailable in extracted text
James Coyne
Delegate of the Civil Aviation Safety Authority
24 May 2006