Lycoming debuted a new electronic ignition meant to be a bolt-on replacement for conventional magnetos. Dubbed the Electronic Ignition System (EIS), the devices have no internal moving parts and slip right into conventional magneto housings on four-cylinder Lycoming engines.
Currently the EIS is available only for the experimental market but the company is working toward FAA certification for retrofits. One exception is the CarbonCub XCub, which debuted this system with its CC393i. Also, six-cylinder versions are in development.
For experimental aircraft, variable timing will be available later via a built-in sensor to measure manifold pressure and assign a variable ignition curve based on estimated load. Lycoming says the EIS will have one advance curve only and be factory configured for each engine model. For now, though, the available EIS modules are fixed timing only.
For certified aircraft, the EIS initially will be configured for fixed timing, just like a magneto. The initial approvals are expected in the third quarter of this year, with Lycoming continuing development of a variable-advance version in early 2020.
In either fixed or variable timing configuration, the EIS requires ship’s power to function; it is not self-powering. Because of that, Lycoming recommends retaining one conventional magneto when a redundant power source is not available. For dual installations in certified aircraft, Lycoming expects to provide an external, redundant power source. For experimentals, builders are encouraged to construct electrical systems with sufficient redundancy or purchase the Lycoming-built backup battery system.
Prices have not been set, but Lycoming claims they will be competitive with other systems on the market.
Do they still go “bang” when doing a standard mag check?
Worse! Unlike a mag, when switched back on, the computer has boot time. Big Bang! Especially when doing a full power in flight mag check. Only doing that one time, haha! Must learn to go low power, then move switch, then bring power back.
You will only get a “bang” during a standard mag check if you inadvertently turn the mag switch off then on again.
Lets walk through it:
This is not a magneto, it’s works more like the old Ford EDIS coil pack from the 1990’s.
It works on the principle of “wasted spark”, so it also throws a spark into the the exhaust side.
That’s not a problem since there is normally no air/fuel available when that happens.
It also takes ~3 revolutions from the time this unit is energized until it actually start to fire.
My normal mag check is the sequence: at 1800 rpm switch from Both to Left only, then to Right Only, and then back through Left only back over to Both. I get a “BANG” every time since there are at least 3 revolutions of raw air/fuel mixture in the exhaust side when coming off the Right only position back through Left Only on the way back over to Both.
Only work-around I have is to throttle down after going to Right only to minimize the fuel/air in teh exhaust side when trying to get it back over to Both. An no, I’n not going to drill holes for 2 toggle switches to replace my stock rotary mag switch.
the devices have no internal moving parts ..
whats the drive gear for then??