Hi there!

After decades building RC boats, tanks and vehicles, I decided to give RC planes a try.

I'm not interested in acrobatics, just smooth, relaxing flights.

So far I have a ECO 2212C 988 with its ESC, a Flash 7 2.4 radio system as a first model I will build a FT Simple Cub or a FT Simple Storch (made of foam).

Which prop size would fit best here? I have a 9x6 but it seems to be too much for the motor and the esc and I don't think I will need so much power.

I'd appreciate any help.-

Hi!
Never heard of the plane you mentioned and the radio....
A scale plane like the Piper CUB or a German Storch is not a good way to start !
The best way to learn flying R/C is joining a club and get help from experienced fliers!
I'm old school and like glow powered planes better than electrics because you get more flying time with those as you don't have to charge any batteries. With a glow engine you just fuel up and go flying, Takes just a minute to fuel it!
A good size for high winged plane is 160-180cm in span as those planes are easier to see than smaller ones and more stable in flight when it's windy.

I had a couple of glow plug planes in the past and I prefer to use electrics rather than messing with fuel, noise, glow plugs.

Most old schoolers find it difficult to accept modern times, and this applies to all aspects in life.

Your post has me asking two questions:
1) What makes someone an "old schooler"?
2) Why do you say that anyone that is an "old Schooler has a hard time accepting modern times?

You paint with a broad brush in that statement.

Most Old Schoolers are not so easily convinced the so called modern times are better. They have extensive knowledge and experience with their old school methods and maybe simply do not want to learn something new. Or perhaps the Modern eliminates a part of the hobby they like? The old adage applies, "If it works, don't Fix it!"

Jeez guys, how about taking the debate as to who is a an old fart and who is a young goober to private messaging, Mkay?

To answer the OP's questions- The great thing about Flite Test is that there are usually extensive threads about what works well with their planes. Do a little searching and see what you find.

I'm going to suggest starting with a true trainer plane though. Your previous RC experience will help some, but flying skills still take time to develop.

An instructor is also a very good idea. Flight isn't like RC cars and boats where you just bash around until you get the hang of it. There are some things to know, and an instructor is the best way to learn them.

Welcome to the forum. We'll be here to help however you decide to go about it.