plain sailing

noun

1. Navigation. sailing on waters that are free of hazards or obstructions. Compare plane sailing.
2. an easy and unobstructed way, course, or plan:

   As an heir to a large fortune, he looked forward to financial plain sailing.

plain sailing

noun

1. informal.
   smooth or easy progress
2. nautical sailing in a body of water that is unobstructed; clear sailing Compare plane sailing

Word History and Origins

Origin of plain sailing¹

First recorded in 1800–10

Idioms and Phrases

Easy going; straightforward, unobstructed progress. For example, The first few months were difficult, but I think it's plain sailing from here on . Alluding to navigating waters free of hazards, such as rocks or other obstructions, this term was transferred to other activities in the early 1800s.

Example Sentences

The deal may not be plain sailing, though, most notably due to the two companies’ differing business models.

From Singularity Hub 

“That is a fast boat, and we can never catch her in plain sailing,” said Allan Harding.

From Project Gutenberg

They were told the guns could go on their own carriages, as it would be a stiff pull over Akra Dagh, but plain sailing after that!

From Project Gutenberg

It was all such plain-sailing for him, she pointed out; he did not like this Home Rule, and therefore he must vote against it.

From Project Gutenberg

It was understood between us that you would prepare Mrs. Burnside, so that it might all be plain sailing.

From Project Gutenberg

This was all plain sailing enough; the report was good enough to justify his exercising his option.

From Project Gutenberg