Wonderful - Thank you both very much. This is great news!

Our destination is just outside of Trier west of Frankfurt and it looks like the train will go northwest through Koblenz/Cologne. Koblenz would be a good idea but I think the fewer changes would be best for my mother.

RalfKrippner - to clarify: when we get off the plane we will pass through customs/luggage claim and exit into Terminal 1. Then I will go from Terminal 1 to the Frankfurt am Main Flughafen Fernbahnhof to collect our luggage at the AiRail terminal (Fernbahnhof), bring them back to Terminal 1 and collect our rental car and be on our way - correct?

I presume there must be some security/customs check-points we'd need to pass through after collecting our luggage from the Fernbahnhof baggage claim area - is that correct? Which likely means my mother will need to be present for that, otherwise I'd prefer she rest in Terminal 1 while my wife and I collect the luggage.

And to reiterate: we would the same in reverse - we park our rental, bring our luggage to the AiRail Checkin at the Flughafen Fernbahnhof (identical place where we picked them up?) - which should automatically be transferred onto our plane - then proceed to go through security at Terminal 1 with our pre-printed boarding passes and proceed to our gate.

The Uebersichtsplan T1 and T2 map is oriented from South to North (upside down) and is a little confusing! I see the baggage claim at the long-distance train level... It's been a while since I got off the plane in Frankfurt.

Thank you both so much - this is a huge relief. Going to book the rental car now.