A pocket sailing school, built two miles from the breakwater.

Oh Sail started as a question: why do flight students get ground school, while sailing students get thrown straight onto the water with a boom swinging at their head? We built the missing step: a simulator that teaches the perceptual skills of sailing (reading wind on water, feeling the no-go zone, judging a dying approach to a dock) in the harbor where we actually sail: Marina del Rey, California.

The physics are real. Apparent wind, polar performance, leeway, wind shadows computed from the actual breakwater. The coach is opinionated. The pelican is non-negotiable.

We think feedback is the actual product. Every run produces a track, a debrief, and data. For you, that’s deliberate practice; the long game is simply more people falling in love with sailing, because the scary part got cheaper than free.

The name

Oh Sail is the small thing you say when the canvas fills, the boat leans into its work, and the tiller goes quiet in your hand. That moment is the whole product. Everything here exists to get you to it sooner, and to make sure you know what to do when it arrives.

The crew

Kjell Nelson

Sailing Instructor

Bareboat yacht skipper out of Santa Monica Bay, and a lifelong scientist, inventor, and mentor: microbiology to bioengineering to point-of-care diagnostics, including an NSF project coating boat hulls against fouling. Kjell is the seamanship conscience of Oh Sail. If a lesson would not hold up at the helm, it does not ship.

Mark Koester

Builder

Product lead, endurance athlete, and longtime quantified-self builder. Oh Sail is what happens when someone who instruments his own training gets curious about how people actually learn boats. Real physics, real chart data, and a pelican with strong opinions.

Want to follow along? Leave your email and we will write when new harbors and lessons open. Or write to us at hello@ohsail.com or through the contact form. We read everything.