Chapter 76 - Engine Controls - Discovery Aviation

1 Engine Controls XL-2 AIRPLANE Chapter 76 Engine Controls P/N 135A-970-100 Chapter 76 REVISION ~ Page 1 of 18 Engine Controls XL-2 AIRPLANE Chapter 76 P/N 135A-970-100 Page 2 of 18 REVISION ~ Copyright 2009 All rights reserved. The information contained herein is proprietary to Liberty Aerospace, Incorporated.

2 It is prohibited to reproduce or transmit in any form or by any means, electronic or mechanical, including photocopying, recording, or use of any information storage and retrieval system, any portion of this document without express written permission of Liberty Aerospace Incorporated. Engine Controls XL-2 AIRPLANE Table of Contents SECTION 76-00 GENERAL 5 SECTION 00-01 FADEC SYSTEM DESCRIPTION AND FUNCTIONAL OVERVIEW 6 SECTION 00-02 HEALTH STATUS ANNUNCIATOR AND POWER TRANSFER CHECK PROCEDURES 7 FADEC POWER TRANSFER CHECK 8 SECTION 76-10 POWER control

3 11 SECTION 10-01 POWER (THROTTLE) CABLE REMOVAL AND REPLACEMENT 12 THROTTLE CABLE REMOVAL 13 THROTTLE CABLE INSTALLATION 14 THROTTLE CABLE RIGGING PROCEDURE 15 SECTION 76-20 EMERGENCY SHUTDOWN 17 P/N 135A-970-100 Chapter 76 REVISION ~ Page 3 of 18 Engine Controls XL-2

4 AIRPLANE Chapter 76 P/N 135A-970-100 Page 4 of 18 REVISION ~ PAGE LEFT INTENTIONALLY BLANK. Engine Controls XL-2 AIRPLANE Section 76-00 General This Chapter provides a descriptive overview of the control systems for the IOF-240-B Engine installed on the airplane. Detailed information for routine line maintenance for each Engine subsection or system is provided in the appropriate Chapter .

5 More detailed information for repairs and maintenance on systems and components specific to the IOF-240B Engine FADEC system are provided in the current release of the Teledyne Continental Motors Maintenance Manual for IOF-240-B series engines, TCM p/n: M-22. The IOF-240B Engine installed in the airplane is equipped with a PowerLink Full Authority Digital Engine control (FADEC) manufactured by the Aerosance Corporation. This system Controls both ignition timing and fuel delivery to the Engine . The ignition section of the FADEC replaces the conventional magneto system, while the fuel section replaces the carburetor or hydro-mechanical fuel injection system found in conventional installations.

6 In a fixed-pitch propeller installation such as this airplane, primary power control is through a single throttle lever. Fuel mixture is controlled by FADEC; there is no cockpit mixture or pitch control . The following are additional Engine Controls : Include a manual knob for selection of alternate induction air (used only in case of blockage of the primary induction air filter), An ignition switch to select between the L and R channels of the FADEC system, FADEC A and FADEC B power switches to control electric power to the FADEC system A FADEC Health Status Annunciator (HSA) which indicates various FADEC malfunctions or operating modes A Boost Pump Mode Switch (BPMS)

7 An emergency fuel shutoff P/N 135A-970-100 76-20 REVISION ~ Page 5 of 18 Engine Controls XL-2 AIRPLANE 76-20 P/N 135A-970-100 Page 6 of 18 REVISION ~ Section 00-01 FADEC System Description and Functional Overview Components of the FADEC system include dual Electronic control Units (ECU) mounted on the Engine compartment firewall. Each contains dual redundant microprocessors and dual high voltage coil sections. Each microprocessor Controls ignition for two cylinders. Complete failure of a single microprocessor and/or its associated high voltage section will result only in the loss of spark to one of the two spark plugs in the two affected cylinders; fuel injection functions are shared by all four microprocessors in the system.

8 In the extremely unlikely event of complete failure of an entire ECU (both processors and both high voltage sections), the Engine will continue to run at reduced power, as the ECU s are arranged to control cylinders paired on opposite sides of the Engine . The remaining cylinders will respond normally to cockpit Controls . Figure 76-1 Fuel Supply System Engine Controls XL-2 AIRPLANE An Engine -mounted sensor set supplies information to the two ECUs.

9 Sensors include cylinder head temperature for each cylinder, exhaust gas temperature for each cylinder, temperature and absolute pressure of the air in the induction manifold, pressure of fuel supplied to the fuel injector nozzles, Engine rotational speed, and crankshaft position. Engine speed and crankshaft position are sensed by dual magnetic pickups installed in the crankcase, which sense the passage of targets (holes) milled into the camshaft drive gear. Signals from the magnetic sensors are further conditioned by a unit installed on the Engine accessory case in the left magneto opening.

10 The right magneto opening is covered. In addition, in fixed-pitch propeller installations, throttle position is sensed to the wide-open-throttle (WOT) position or RPM. When WOT is sensed, the FADEC fuel system adjusts fuel flow for the best-power configuration. At any other throttle systems, the FADEC fuel system adjusts flow as required for best-cruise operation. To provide system redundancy, many sensors, including Engine speed and crank position, intake manifold pressure and temperature, and fuel pressure, are installed in duplicate. In addition, should all information from any sensor(s) be lost, system software will revert to internally stored default values to allow continued Engine operation.