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Soft Start Mags for Rotax 912ULS?

Soft Start mags?

Does anyone know if I need one or two soft start mags to get the benefit?

I think this depends on the SC key switch behavior as in: does the switch start on one mag or both?

Some a/c crank/start on one mag, then when you release the starter switch/key it energizes both. I'm not sure about our SC starter switch, so unsure if I need one or two soft start mags. Does anyone know on this?

Also - will I need an LOA to exchange my mags for this Rotax factory part (I don't think so)?

Dave

Tags: Mag, Rotax, Soft, Soft-Start, SoftStart, Start

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Permalink Reply by Dave Bonnar on May 22, 2019 at 6:30

As in all things aviation "it depends",

If your a/c can start on the left or right mag independently as many can, then you only need one for the 'start' side.

The SportCruiser uses a rotating key switch. When it's on 'start' and 'run', it has energised both modules. Best to have them in synch so using two soft start modules seems right to me. Not sure if it's a big deal, but having one module retarded for 5 seconds while the other is not couldn't lead to good things. Hmm, fuel would fire on the 1st spark, which would be the non-soft start mag. Hmm, then the effect of the soft start mag would be null. Buy two.