I am traveling in Eastern Europe right now and I have definitely seen instances in airports where both the airport personnel and the the traveler were obviously not native English speakers however English was the only way they could communicate. It seems that English is the international language of air travel. At least for now.

Given that most European countries all speak different native languages but also speak widespread English as a common, second language, it seems a reasonable thing to request in an airport in a European capital where there are likely travelers from many different, non-German speaking countries.

Not in the US, but we like to do that in Spain.

There is a high chance that a random traveler will understand English. The same chance for German is way lower, including in Germany.

Is German the most-spoken second language across the whole continent where the US is located?

Is German the most commonly spoken language in North America?