- For solo flyers sufficient Spanish knowledge

They don't want to have to provide translators in the plane with you.
This is a very reasonable requirement - you are alone in a foreign
country. Speak the language - at least well enough to get by.

The whole point of a "guided tour" is that the tour members depend on
the tour arrangers for certain things. They are being explicit that
basic language assistance is not one of those things if you choose to
fly alone.

Jose
--
Get high on gasoline: fly an airplane.
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