So what's the deal with ACT

I think the consensus around here is that the ACT causes more crashes than it prevents. There are some not-uncommon situations that confuse it and cause it to do the wrong thing at just the wrong time.

The ACT relies on the sky being lighter than the ground (grass). If it sees that the upper sensor is not detecting more light than the lower sensor, it will take control and try to correct that. If you fly over sand or concrete, or if you fly at sunset or sunrise, it may make the wrong assumption.

Even if you are a bad pilot (as I am), you learn more from your own mistakes than from having control yanked away from you at a critical moment.

The best advice is to just pull the ACT plug off of the RX. That won't hurt anything. There are ways to turn it off via the TX, but it can turn on again when you don't expect it.

Regards,
-Peter

Minimum-turn it off.
Better-disconnect it.
Here's my old and tired rant on the subject:

ACT works by using sensors looking at the ground and horizon. It differentiates shade (dark ground/light sky) and tries to keep them that way. If the plane goes up or down too fast and the shade isn't right it 'takes control' AWAY from you and essentially neutralizes the controls. You can achieve the SAME result just by letting go of the sticks. Of course new pilots don't they just over correct some more. The high wing Cub will self correct in time but not immediately.

If ACT kicks in up high, no problem, but then letting go of the sticks would work also. If it happens down low you have NO ABILITY TO CORRECT SINCE CONTROL IS REMOVED! Just like letting go of the sticks once you pointed it straight at the ground from 20 feet up it's going in! Its not useful down low and wrecks more planes than it saves, but it sure sounds good to new fliers. Since they can't fly anyway and they wreck frequently they figure it would only have been worse without it. They can't differentiate between their short comings and ACT's problems.

So it works up high where you don't really benefit from it and screws you up down low when it doesn't help. It also gets totally confused when you fly over water, snow or very light ground surfaces (light concrete, sand) since it doesn't know what to do with that. It's NOT SMART, it's just a shade sensor. What it does best is lure in new fliers. Great marketing scheme. It's a real piece of junk.

If you just got to see, turn it OFF, take it HIGH, and turn it on. Don't do this down low, you'll be sorry.

If you can get yourself some experienced help for the first flight it will go WAY WAY better. People say you can learn the Cub by yourself but with a few RARE exceptions the price in crashes, parts and grief is high. Few first flights last more than 30 seconds, most often significantly less.

You get in the cycle of crash > broken plane > how do I fix it > did I fix it right > now it's not trimmed out properly > flies badly >more crashes >even worse now.....it can get frustrating.
I know, I know, you bought it to learn to fly but at first learning to fix it is likely to be your real lesson.

Getting help for the first DOZEN flights is even better. You work that out with the instructor.
Buddy box connections is optimal if possible.