The Jeanneau Sun Fast 42 1996 vs Jeanneau Sun Odyssey 509 2011 comparison sits squarely in the category of decisions where specs alone won't tell the whole story — intended use, storage, and long-term ownership costs all factor in.
Size is the most obvious dividing line here. The Jeanneau Sun Odyssey 509 2011 measures 50,6 feet overall (2011), giving it roughly 8,8 additional feet of deck space compared to the Jeanneau Sun Fast 42 1996 at 41,8 feet (1996). Weight tells a clearer story for trailering families: the Jeanneau Sun Odyssey 509 2011 tips the scales at 30 644 lbs — 11 684 lbs less than the Jeanneau Sun Fast 42 1996 at 18 960 lbs. That difference is meaningful if you're working within a half-ton or three-quarter-ton truck's tow rating, especially once you factor in a motor, gear, and fuel.
The Jeanneau Sun Odyssey 509 2011 tops out at 75 hp. Engine specs for the Jeanneau Sun Fast 42 1996 aren't listed — confirm with a dealer before selecting an outboard.Fuel capacity breaks the other way: the Jeanneau Sun Odyssey 509 2011 carries 63 gallons versus 40 gallons in the Jeanneau Sun Fast 42 1996. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.
For family outings this is probably the sharpest distinction between the two. The Jeanneau Sun Odyssey 509 2011 is rated for 15 passengers, while the Jeanneau Sun Fast 42 1996 caps at 12. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Jeanneau Sun Odyssey 509 2011 could be the deciding factor.
Displacement is where these two sailboats genuinely part ways. The Jeanneau Sun Odyssey 509 2011 displaces 30 644 lbs — a 11 684-lb difference over the Jeanneau Sun Fast 42 1996 at 18 960 lbs. That gap separates two entirely different categories of sailing: the heavier boat is built for offshore passage-making and load-carrying, while the lighter hull rewards performance sailing and easier handling in lighter air.
Both boats draw a similar depth — 7,6 ft and 7,6 ft respectively. Marina access and anchorage options should be broadly equivalent between the two.
The Jeanneau Sun Fast 42 1996 uses Sloop rigging. Helm style differs too: the Jeanneau Sun Fast 42 1996 uses a 1 helm wheel versus a 2 wheels on the Jeanneau Sun Odyssey 509 2011. Wheel helms give better leverage and visibility on larger boats; tillers offer direct feedback and simplicity on smaller ones. The Jeanneau Sun Odyssey 509 2011 has a documented auxiliary engine of 75 hp.
Hull speed is rated at 9,1 knots for the Jeanneau Sun Odyssey 509 2011 and 7,9 knots for the Jeanneau Sun Fast 42 1996. For extended cruising, water capacity matters: the Jeanneau Sun Odyssey 509 2011 carries 163 gallons versus 93 gallons on the Jeanneau Sun Fast 42 1996 — a significant advantage on longer passages where watermaker or provisioning stops aren't guaranteed.
Bottom line: The Jeanneau Sun Odyssey 509 2011 is the offshore and bluewater choice — at 30 644 lbs displacement and 51 ft it has the load capacity, range, and seakeeping for extended passages. The Jeanneau Sun Fast 42 1996 at 18 960 lbs is the more nimble, accessible option — easier to single-hand and better suited to coastal and inland sailing.