FRA SkyLine, before or after security?
 

I'm going to nonrev out of FRA next week and I will need to bounce between Z/A and C gates. Is the SkyLine train before or after security? If it's before security, then can I walk behind security between the two terminals and how long will it take?

It is both. There is access both pre and post security (and those passengers do not mix, each will be in a different car). So really depend on exactly what will be your itinerary.

Actually both parts of the train are outside security. One half is landside / Schengen, the other is non-Schengen.

There is no secure path.

A to C you just walk through the public area and have passport control and security at C.

Z to C you take the train and have transfer security at C.

The FRA MCT of 45 minutes would be cutting it fine normally. Things are little messy right now so hopefully you have longer than that...

I'll be trying for flights to the US on LH, UA, AA and 4Y, so I was hoping to go back and forth between Z to C, for how ever long it takes. Is it security in both directions, C to Z and vice versa?

Yes. There is no secure path between Z and C.

🤞you get something sooner rather than later...

I'm a bit confused on this, but likely should not be.

My scenario: We're staying at the Marriott which is connected to Terminal 1. We'll be flying on AA which is out of Terminal 2. So I get that we will talk from the hotel to Terminal 1 where we will catch the Skyline train.
1. I believe we will check in and do passport control in Terminal 2; true?
2. I believe the Skyline is before any security checks; it is open to the general public; true?

Both correct. Walk to Terminal 1, follow signs to Concourses D and E up a flight of escalators, take Skyline, exit Terminal 2, escalator down again, walk to check-in counters.
Or just take the bus from ground level near the Marriott. Not as fancy but probably faster.