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-   -   Lycoming New Electronic Mag Osh 2019 (https://vansairforce.net/community/showthread.php?t=173730)

PilotjohnS 07-27-2019 09:18 AM

Lycoming New Electronic Mag Osh 2019
 
At Oshkosh 2019, Lycoming announced their new electronic ignition system. It replaces the traditional magneto.
In the booth, I talked to the Subject Matter Expert about it.
I looks like a regular mag, uses a P lead and requires a redundant power source for certified aircraft.

The advantage I see is that it does not run software like a E Mag, but rather uses a Programable Logic Device that gets hard encoded during manufacturing. This means no software to update or get corrupted, but requires factory returns for firmware updates.

One disadvantage is that it doesn't self generate its own electricity, but the SME is working on that.
Another is the mechanical tach drive is tight. I talked to Garmin and the G3x can sense the RPM from the P lead if it works the same as the mechanical tachs.

rv6ejguy 07-27-2019 09:31 AM

Already discussed. Unit is a Surefly. https://www.aopa.org/news-and-media/...gnition-system

DanH 07-27-2019 10:54 AM

Yes, Surefly.

Lycoming's initial interest is the certified fleet operator who is currently spending a lot of money to overhaul Slicks at 500 hour intervals. The Surefly concept incorporates the Slick mag cap and harness, as well as the standard aircraft plugs, so the swap is painless. The installing mechanic adds only a power lead.

Their long term interest is the Type Certificate market...standard equipment EI on production aircraft.

My understanding is that Lycoming will specify a specific part number for each engine model. Initially all will be fixed timing, no advance schedule. They do plan to add an advance option, again tailored to specific engine model.

There were considerable revisions of the original Surefly to arrive at the current shared version. The Lycoming reps stated there will be no physical or mechanical difference between a standard Surefly purchased directly, and the certified Lycoming version. The only difference will be Lycoming's choice of advance schedule, which will vary by part number. At this time, Lycoming considers the advance schedules determined in the dyno rooms at Williamsport to be proprietary; they will not publish them.

The Surefly currently sold for EAB use offers a user-set choice of 18 through 30 degree fixed timing, as well as 18 to 30 base timing with an advance schedule. The current advance schedule is "one fits all", and as noted in previous discussion, appears to be fine for a parallel valve, while being too advanced for an angle valve. It will be interesting to see what becomes available after Lycoming settles on its own schedules.

bkervaski 07-27-2019 11:23 AM

Quote:

The installing mechanic adds only a power lead.
Doesn't it also need a manifold pressure line?

DanH 07-27-2019 11:27 AM

Quote:

Originally Posted by bkervaski (Post 1362306)
Doesn't it also need a manifold pressure line?

Not for the targeted retrofit market, which is fixed timing.

rv6ejguy 07-27-2019 11:34 AM

Photos show a MAP connection point on the rear of the units which you'd have to connect to have MAP advance, which may be of more importance to Experimental users. As Dan points out, the Cert market is huge and probably what Surefly and Lycoming care about most. The Experimental market already has plenty of choices offering both more features and lower prices in some cases. Electroair also offers certified EIs but the Surefly price point will put a lot of hurt on their sales IMO.

If these are reliable, they should offer a fair cost savings to fleet operators jamming a lot of flight time per day on their engines. Good move on Lycoming's part, this should bring in a lot of revenue for them though it may hurt the mag overhaul shops.

bkervaski 07-27-2019 11:36 AM

Quote:

Not for the targeted retrofit market, which is fixed timing.
So, if I understand correctly, without the manifold pressure tie-in you wouldn't get the starting benefits with the Lycoming part, you would have to use the Surefly part.

Toobuilder 07-27-2019 02:19 PM

Quote:

Originally Posted by bkervaski (Post 1362313)
So, if I understand correctly, without the manifold pressure tie-in you wouldn't get the starting benefits with the Lycoming part, you would have to use the Surefly part.

If by "starting", you mean engine start, the MP line has little to do with that. All ignitions need to have a "start retard" mode to prevent kickback. This typically is sensed by low RPM or a discrete signal from the starter circuit, not MP.

But it does bring up a point of Lycomings intent WRT starts... Does it have this retard circuit or is the EI dead when cranking?

DanH 07-27-2019 04:25 PM

A MAP line has nothing to do with starting. Start retard is built in.

With a Surefly and one non-impulse mag, start using the Surefly, while the magneto P-lead is grounded.

With a Surefly and an impulse-coupled mag, start using both.

With two Surefly units, start using both.

DanH 07-27-2019 04:51 PM

Quote:

Originally Posted by rv6ejguy (Post 1362312)
Photos show a MAP connection point on the rear of the units which you'd have to connect to have MAP advance, which may be of more importance to Experimental users. As Dan points out, the Cert market is huge and probably what Surefly and Lycoming care about most.

As noted previously, Lycoming intends to establish proprietary advance values for certified installations, at the Type Certificate level. In other words, they intend to deliver ignition advance on new engines and aircraft, as well as within the aftermarket

The Lycoming branded units are identical to the Surefly branded units. An EAB user may prefer the Lycoming vetted and certified advance values. The interesting thing to watch is what Surefly will do about their one-size-fits-all advance values when their partner is saying one size doesn't fit all.


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