следующий рейсами

I have the following phrase, whose meaning is rather clear, but I can't fit as I would like the cases:
Узнайте по телефону о времени отправления самолётов, следующих рейсами: Москва - Берлин, Москва - София, ...
My problem is with следующи. It can be an adjective (next, following) or a participle (that follows; proceeding to),
In both meanings an instrumental case follows, what is somewhat strange for me.
Trying to find a sense I translate: the departure time of the planes flying / traveling in the travels: Moscow - Berlin,...
However I find my translation somewhat free from what is written in Russian. Isn't it?
Thanks.

следующий - здесь причастие (participle) от следовать (to follow, to proceed to, to go/fly in this case/ to).
You may also meet проследовать (to pass by)

Thank you.

следующий - participle from "следовать". Следовать = go, fly.

рейс = flight (or 'destination' if it's a bus, coach).

Thank you.

"Следовать рейсом" - это как "идти путём".

Thanks. That was my problem; I hadn't this use of instrumental case; I add to my list. Now I look in my dictionary: путь: водным путём: by sea, on the water; сухим путём; on land.
Thank you.