smooth sailing; everything going well
A yojijukugo used to wish someone a smooth journey or to describe things progressing favorably without obstacles. Often used in farewells or as a congratulatory phrase.
I wish you smooth sailing on your new journey.
The project didn't go as smoothly as we'd hoped.
順風満帆 also means smooth progress, but it emphasizes a favorable wind filling the sails, often used for business or life going well. 一路順風 is more specifically about a journey or the start of something.
A yojijukugo composed of 一路 (one road, straight path) and 順風 (favorable wind). The exact historical origin is uncertain, but it follows a common Chinese-derived four-character pattern for auspicious phrases.