Eagle EMS Q & A

Eagle EMS Questions & Answers

Click on any of the links below to go directly to a specific question. Or click on this link to go to the first question and then scroll through the list.

1) What are the advantages of the EAGLE Engine Management System?

2) What engines is the EAGLE EMS available for?

3) What comes in the EAGLE EMS kit?

4) How long will it take to install the EAGLE EMS, and what do I need to do to my airplane?

5) Why will I need a custom-built wire harness?

6) Why does the EAGLE EMS need its own battery?

7) What sort of battery do I need to get for the EAGLE EMS, and why do I need to provide it instead of having it come with the kit?

8) Does the EAGLE EMS have to be calibrated for my airplane / engine combination?

9) Does the EAGLE EMS provide variable ignition timing?

10) What inputs does the EAGLE EMS use?

11) Don't I still need to watch EGT and CHTs?

12) How can I read fuel flow?

13) Will I be able to hand-prop my airplane?

14) What sort of fuel filtration is required with the EAGLE EMS?

15) At what interval should the 10-micron fuel filter be replaced?

16) What sort of fuel pump is required for the EAGLE EMS?

17) What about the use of other fuels, like autogas?

18) Will I be able to use auto-style spark plugs?

19) How much does the EAGLE EMS weigh?

20) Why doesn't the weight comparison chart include the backup battery for the EAGLE EMS?

21) What is the warranty for the EAGLE EMS system?

22) What will the fuel savings be with the EAGLE EMS?

23) What if I want to climb at 200 degrees rich of peak and cruise at 100 degrees rich of peak?

24) Does the EAGLE EMS provide feedback to the pilot with warnings or system status?

25) What happens if a component in the system fails in the Electronic Control Unit?

26) What happens if an ECU malfunction indicator light does come on in the cockpit?

27) What happens if you have complete ECU failure?

28) Where can I get my EAGLE EMS and how much will it cost?

Q: What are the advantages of the EAGLE Engine Management System?
A: The Eagle EMS provides full electronic control of fuel injection and ignition. The benefits are readily apparent!
		Smoother running, especially at idle, allowing lower idle speed
		Elimination of mixture control lever, reducing pilot workload
		Significantly improved starting performance, extending battery and starter life
		Automatic fuel and ignition compensation for atmospheric conditions
		Cleaner-running engine, less carbon buildup on internal engine parts, longer spark plug life
		Redundant fuel control

Q: What engines is the EAGLE EMS available for?

A: The Eagle EMS is available for Lycoming 320, 360, and 390 series engines.

Q: What comes in the EAGLE EMS kit?

A: The Eagle EMS kit comes with most of the components needed to install the system: the Electronic Control Unit (ECU), the power management module, a fuel distributor/filter assembly, timing sensors (and all other required sensors), ignition coils, spark plug wires, a power management module, mounting hardware, a throttle body, an annunciator panel, injectors, and a wiring harness. You only need to provide fuel lines, a battery (appropriately sized for your aircraft) for the Eagle, fuel pumps, magneto gears, and circuit breakers to provide power from the aircraft bus.

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Q: How long will it take to install the EAGLE EMS, and what do I need to do to my airplane?

A: The Eagle EMS will be installed and tested on your engine at the engine shop. When you install the engine in your airplane you will need to mount the ECU, ignition coils, annunciator panel, battery, and power management module.

You will then measure the required wire harness lengths, fill the measurements in on a form, send in the form, and receive a custom-built wire harness from the factory.

Q: Why will I need a custom-built wire harness?

A: Because you will be mounting the Eagle's key components, and the exact location of the components will vary according to the dictates and constraints of your airplane. Therefore, there's no way to tell in advance what the wire harness lengths will be. After you install these components, the factory will need the measurements from your airplane in order to furnish you with a suitable wire harness.

Q: Why does the EAGLE EMS need its own battery?

A: In case of electrical system failure, the Eagle needs to have its own dedicated battery independent of the rest of the aircraft's electrical system. The battery you provide (again, appropriately sized for your aircraft) will be monitored and charged by the Eagle EMS power management module. This module continuously monitors the aircraft power, maintains the Eagle's battery at full charge, and automatically switches to backup power if necessary.

Q: What sort of battery do I need to get for the EAGLE EMS, and why do I need to provide it instead of having it come with the kit?

A: The Eagle EMS draws approximately 1.6 amps. The dedicated battery needs to provide you with enough time to land safely in case of main electrical system failure. The battery's size and weight also need to be suitable for your airplane. For those reasons, we leave the specific battery selection up to you, instead of attempting to provide a battery that will work for any aircraft and any application.

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Q: Does the EAGLE EMS have to be calibrated for my airplane / engine combination?

A: The Eagle EMS does require some calibration based on different installation variables and the desires of the aircraft owner. The Eagle EMS will be sold through qualified engine shops which will be able to calibrate the systems in their engine test cells and provide follow-up support in the event that changes are desired.

Q: Does the EAGLE EMS provide variable ignition timing?

A: The Eagle EMS will be delivered from the factory with fixed timing matching the magneto timing. The timing can be adjusted based on engine RPM and manifold pressure if desired. These changes would be made by the qualified engine shop based on input from the customer. The system will not have cockpit-adjustable timing.

Q: What inputs does the EAGLE EMS use?

A: The Eagle EMS uses engine speed and manifold pressure as the primary inputs to determine fuel flow and ignition timing. We also measure inlet air temperature, barometric pressure, and cylinder head temperature. These inputs are used to compensate for atmospheric changes and to prevent overheating of the engine.

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Q: Don't I still need to watch EGT and CHTs? (exhaust gas temperature and cylinder head temperatures)

A: The Eagle EMS is a brand-new electronic injection system. EGT and CHTs are used in leaning a carbureted engine. However, with electronic ignition, you do not have a mixture control so you can't lean your engine with them. These temperatures have been taken into consideration when the ECU is set up for operation. With this new system, a new mindset for pilots and mechanics is necessary, because we are now depending on the Electronic Control Unit (the ECU) to watch CHTs and lean the engine optimally. Manual leaning is no longer needed.

Q: How can I read fuel flow?

A: We can determine fuel flow by the pulse width and the number of pulses, and fuel pressure. We may be able to display this information on a small screen in the cockpit. We are working on this possibility and also on displaying other engine operating parameters. Please note that the Eagle EMS injectors are very accurate in measuring fuel. Therefore, if you use any turbine (Roto) flow meters that are inline, the readings you obtain from these meters will not necessary agree with the true fuel flow.

Q: Will I be able to hand-prop my airplane?

A: We do not recommend hand-propping an airplane with the Eagle EMS installed.

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Q: What sort of fuel filtration is required with the EAGLE EMS?

A: The Eagle EMS incorporates a large 10-micron fuel filter that is easily replaceable. The aircraft should be equipped with a 150-micron or better screen upstream.

Q: At what interval should the 10-micron fuel filter be replaced?

A: Replace the filter after the first 25 hours of operation. After that, replace the filter every 100 hours of operation, or at annual inspection, whichever occurs more frequently.

Q: What sort of fuel pump is required for the EAGLE EMS?

A: The Eagle EMS requires 20-35 psi. You should use a standard Lycoming diaphragm pump (as is used with IO series Lycoming engines) and an electric boost pump with a 20-35 psi output.

Q: What about the use of other fuels, like autogas?

A: We never recommend the use of auto fuel because it can contain alcohol, is of variable quality, and has a reduced shelf life. The Eagle is calibrated for avgas. Auto gas with ethanol could require a completely different calibration, and we are not looking into that at this time. However, the Eagle could use non-alcohol auto gas with little or no re-calibtration.

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Q: Will I be able to use auto-style spark plugs?

A: They would probably work. However, we will not recommend this because modifications would have to be done; plugs, coils and wire harness would have to be changed; and we have no operating data for this modification.

Q: How much does the EAGLE EMS weigh?

A: The Eagle EMS weighs approximately 18.1 pounds. For details, refer to this chart comparing the weight of the Eagle with the weights of fuel injected and carbureted fuel control systems. (The chart will open in a new browser window.)

Q: Why doesn't the weight comparison chart include the battery for the EAGLE EMS?

A: The Eagle EMS battery is a component that you provide, and battery weights can vary widely depending on the specific installation.

Q: What is the warranty for the EAGLE EMS system?

A: The Eagle EMS warranty is the same as our standard warranty: 2 years or 1000 engine hours.

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Q: What will the fuel savings be with the EAGLE EMS?

A: Fuel savings with the Eagle EMS could be significant but will depend on pilot habits and final calibration. For instance, an aircraft which has been flown primarily locally with the mixture on full rich will experience a much greater savings than one flown primarily cross-country with constant attention paid to mixture settings.

The Eagle EMS has the potential for significant reduction in part throttle fuel consumption through careful calibration of fuel and ignition settings. Due to variations in each installation (engine, intake, exhaust, prop, etc.) the desired calibration may be different for each aircraft.

Q: What if I want to climb at 200 degrees rich of peak and cruise at 100 degrees rich of peak?

A: The Eagle EMS will adjust optimally for any given throttle setting, throughout the whole throttle range, regardless of whether you're climbing or in cruise.

Q: Does the EAGLE EMS provide feedback to the pilot with warnings or system status?

A: The Eagle EMS includes an annunciator panel that is installed in the cockpit to provide system status and warnings if the system switches to a backup mode.

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Q: What happens if a component in the system fails in the Electronic Control Unit (ECU)?

A: All systems in the Electronic Control Unit operate continuously. The primary system operates both ignition and fuel injection, and the secondary system operates just the ignition. If any part of the system fails, the system will automatically default and continue engine operation. The only sign that there is a problem will be the indicator light in the cockpit. You won't notice any change in the engine because the system constantly adjusts for any situation.

Q: What happens if an ECU malfunction indicator light does come on in the cockpit?

A: There will be a troubleshooting system in place to help isolate the affected component.

Q: What happens if you have complete ECU failure?

A: The same thing that happens if both magnetos fail simultaneously.

Q: Where can I get my EAGLE EMS and how much will it cost?

A: The Eagle EMS is initially available only through two engine shops: Aero Sport Power and G&N Aircraft. The list price of the Eagle EMS kit is $8,935.40. For installed pricing, contact one of the listed engine shops.

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14800 40th Ave NE Marysville, WA 98271 (360) 651-8282