912 ULS cut-off on landing roll

Yea you need to adjust the idle up to around 1800 rpm or your asking for gearbox problem’s. Buy some manifold pressure gauges or an electronic carb balancer now as your going to need them a lot.

Roger Lee wrote:

Regardless of the temp it's all rpm based. i.e...is yours too low, in the right range or maybe on the high side. So long as it isn't too low you shouldn't have any issues. You shouldn't ever be just sitting there at low idle rpms anyway so then OAT shouldn't be an issue.

Hi Roger - my observation are mainly about landing in hot weather - close the throttle on final, flair, touch down and the engine may stall.

Rarely /never happens in winter, occasionally happens in summer.

Dont have any experience with the UL so can only speculate;

        Inherently smoother idle

        Higher idle setting

        Faster landing speed

Hi Sean,
I set all my idles at 1700 - 1750 with the owners understanding they are never to sit there and idle. All my clients idle at 2K+ rpm. 2200 - 2400 during the colder months. Our temps in Arizona during the summer are anywhere from 100F - 110F and we don't seem to have any issues..

Roger Lee wrote:

Hi Sean,
I set all my idles at 1700 - 1750 with the owners understanding they are never to sit there and idle. All my clients idle at 2K+ rpm. 2200 - 2400 during the colder months. Our temps in Arizona during the summer are anywhere from 100F - 110F and we don't seem to have any issues..

We are in agreement Roger, however I have had my fan stop, just post landing, on perhaps 3 occasion, in 10 years of flying behind the same Rotax.912 ULS.

Each time relatively hot day.

It could be characteristic of the throttle linkage on my ATEC Zephyr - rods/levers going to short cables but I always put it down to "the day".