Beneteau Idylle 15.50 1985 boat specs
Beneteau
Beneteau Idylle 15.50 1985
1985
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VS
Beneteau Oceanis 320 1987 boat specs
Beneteau
Beneteau Oceanis 320 1987
1987
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Beneteau Idylle 15.50 1985 vs Beneteau Oceanis 320 1987 — Same Brand, Different Boat

The Beneteau Idylle 15.50 1985 vs Beneteau Oceanis 320 1987 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 Beneteau Idylle 15.50 1985 measures 51,5 feet overall (1985), giving it roughly 19,9 additional feet of deck space compared to the Beneteau Oceanis 320 1987 at 31,6 feet (1987). Weight tells a clearer story for trailering families: the Beneteau Idylle 15.50 1985 tips the scales at 33 069 lbs — 24 251 lbs more than the Beneteau Oceanis 320 1987 at 8 818 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 power gap is worth calling out. Rated to 85 hp, the Beneteau Idylle 15.50 1985 has a 67-hp advantage over the Beneteau Oceanis 320 1987's 18-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Beneteau Idylle 15.50 1985 carries 132 gallons versus 13 gallons in the Beneteau Oceanis 320 1987. 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 Beneteau Idylle 15.50 1985 is rated for 15 passengers, while the Beneteau Oceanis 320 1987 caps at 9. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Beneteau Idylle 15.50 1985 could be the deciding factor.

Displacement is where these two sailboats genuinely part ways. The Beneteau Idylle 15.50 1985 displaces 33 069 lbs — a 24 251-lb difference over the Beneteau Oceanis 320 1987 at 8 818 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.

Draft is a practical consideration that many buyers underestimate until they're already at the marina. The Beneteau Idylle 15.50 1985 draws 6,0 ft, compared to 4,7 ft for the Beneteau Oceanis 320 1987. That 1,3-foot difference affects which anchorages you can access, which haul-out facilities will take you, and how carefully you need to read the tide tables in shallower cruising grounds.

The Beneteau Idylle 15.50 1985 is rigged as a Masthead-sloop while the Beneteau Oceanis 320 1987 carries Sloop rigging — a meaningful difference in sail handling complexity, upwind performance, and the size of crew you'll need to work the boat comfortably. Helm style differs too: the Beneteau Idylle 15.50 1985 uses a 1 wheel versus a 1 tiller on the Beneteau Oceanis 320 1987. Wheel helms give better leverage and visibility on larger boats; tillers offer direct feedback and simplicity on smaller ones. For auxiliary power the Beneteau Idylle 15.50 1985 carries a 85-hp engine against 18 hp on the Beneteau Oceanis 320 1987. Motoring range and ability to punch through a foul current or enter a tight marina under power will favour the more powerful installation.

Hull speed is rated at 8,3 knots for the Beneteau Idylle 15.50 1985 and 7,1 knots for the Beneteau Oceanis 320 1987. For extended cruising, water capacity matters: the Beneteau Idylle 15.50 1985 carries 238 gallons versus 40 gallons on the Beneteau Oceanis 320 1987 — a significant advantage on longer passages where watermaker or provisioning stops aren't guaranteed.

Bottom line: The Beneteau Idylle 15.50 1985 is the offshore and bluewater choice — at 33 069 lbs displacement and 52 ft it has the load capacity, range, and seakeeping for extended passages. The Beneteau Oceanis 320 1987 at 8 818 lbs is the more nimble, accessible option — easier to single-hand and better suited to coastal and inland sailing.
Measurements / Dimensions
Length overall - Detail51.50 ft
Length overall - Detail31.60 ft
Length - Feet51.5
Length - Feet31.6
Length overall - Meters15.7
Length overall - Meters9.63
Length overall - Inches618
Length overall - Inches379
Beam14.80 ft
Beam10.80 ft
Beam - Meters4.51
Beam - Meters3.29
Beam - Inches178
Beam - Inches130
Draft [max] - Detail6.00 ft
Draft [max] - Detail4.70 ft
Draft [max] - Meters1.83
Draft [max] - Meters1.43
Draft [max] - Inches72
Draft [max] - Inches56
Displacement33069.00 lbs
Displacement8818.00 lbs
Body / Hull
Rudder1 spade rudder
Rudder1 spade rudder
Helm1 wheel
Helm1 tiller
Engine and Drivetrain
Fuel tank capacity - Gal132.1
Fuel tank capacity - Gal13.2
Fuel tank capacity - Liters500.05
Fuel tank capacity - Liters49.97
Horsepower85 hp
Horsepower18 hp
Fuel typeDiesel
Fuel typeDiesel
Drive typeinboard
Drive typeinboard
Performance
Maximum speed8.25
Maximum speed7.05
Maximum speed measureknots
Maximum speed measureknots
Operational Info
Sleeping capacity6
Sleeping capacity4
Cabins3
Cabins2
Head3
Head1
Water capacity237.8
Water capacity39.6
RiggingMasthead-sloop
RiggingSloop
Mast ConfigurationKeel stepped mast
Mast ConfigurationDeck stepped mast
Boat typeSail
Boat typeSail

Beneteau Idylle 15.50 1985 vs Beneteau Oceanis 320 1987 — Common Questions

Which is the larger boat — the Beneteau Idylle 15.50 1985 or the Beneteau Oceanis 320 1987?
The Beneteau Idylle 15.50 1985 is the longer of the two at 51,5 feet overall. The Beneteau Oceanis 320 1987 comes in at 31,6 feet, making it roughly 19,9 ft shorter — a meaningful difference in deck room and overall on-water presence.
Which is easier to trailer — the Beneteau Idylle 15.50 1985 or the Beneteau Oceanis 320 1987?
For trailering, the Beneteau Oceanis 320 1987 has the edge at 8 818 lbs dry weight versus 33 069 lbs for the Beneteau Idylle 15.50 1985. Add a motor (typically 300–500 lbs for an outboard in this class), gear, and a partial fuel load and the difference grows. Lighter is friendlier on smaller tow vehicles and on fuel economy while hauling.
Which boat can handle a bigger outboard?
The Beneteau Idylle 15.50 1985 is rated to a maximum of 85 hp, giving it the larger power ceiling. The Beneteau Oceanis 320 1987 tops out at 18 hp. Keep in mind that maximum ratings are just that — matching the motor to the actual load and usage pattern usually matters more than chasing the ceiling.
How many people can each boat hold?
The Beneteau Idylle 15.50 1985 is Coast Guard rated for 15 passengers, while the Beneteau Oceanis 320 1987 is certified for 9. Note that legal capacity and comfortable capacity aren't always the same thing — on a full day out, most experienced boaters aim for about 80% of the rated number to keep things comfortable.
Which boat has the deeper draft — the Beneteau Idylle 15.50 1985 or the Beneteau Oceanis 320 1987?
The Beneteau Idylle 15.50 1985 has the deeper draft at 6,0 ft, versus 4,7 ft for the Beneteau Oceanis 320 1987. A deeper draft generally means better upwind performance and stability, but limits access to shallow anchorages and some marina berths. Always check the controlling depth of your home port and favourite cruising grounds before committing.
Is the Beneteau Idylle 15.50 1985 or the Beneteau Oceanis 320 1987 better suited for offshore sailing?
For offshore work, displacement and construction are the primary indicators. The Beneteau Idylle 15.50 1985 at 33 069 lbs displacement is the heavier, more load-carrying design — generally better suited to extended passages where seakeeping and provisioning capacity matter most. The Beneteau Oceanis 320 1987 at 8 818 lbs will typically be livelier and more responsive in lighter conditions.
Which is the faster sailboat — the Beneteau Idylle 15.50 1985 or the Beneteau Oceanis 320 1987?
Based on rated hull speed, the Beneteau Idylle 15.50 1985 has an edge at 8,3 knots versus 7,1 knots for the Beneteau Oceanis 320 1987. Keep in mind that actual sailing speed depends heavily on wind conditions, sail trim, bottom condition, and skipper experience — hull speed is a theoretical maximum, not a guarantee.
Which boat is better equipped for long-distance cruising?
For extended passages, fresh water capacity is a key indicator of cruising readiness. The Beneteau Idylle 15.50 1985 carries 238 gallons of fresh water compared to 40 gallons on the Beneteau Oceanis 320 1987 — a meaningful advantage when watermaker installations or port stops aren't guaranteed.
Which boat is wider, and does it affect trailering?
The Beneteau Idylle 15.50 1985 measures 178" wide, compared to 130" for the Beneteau Oceanis 320 1987. The US standard-width towing limit is 8’6" (102") in most states — anything over that may need a wide-load permit. Confirm your specific route requirements with each state's DOT.
Which boat has the larger fuel tank — the Beneteau Idylle 15.50 1985 or the Beneteau Oceanis 320 1987?
The Beneteau Idylle 15.50 1985 has the bigger tank at 132 gallons, versus 13 gallons on the Beneteau Oceanis 320 1987. That 118-gallon difference translates to roughly 356–594 nautical miles of additional range at cruising speed, depending on motor, load, and conditions.
Are the Beneteau Idylle 15.50 1985 and Beneteau Oceanis 320 1987 from the same manufacturer?
Yes — both the Beneteau Idylle 15.50 1985 and the Beneteau Oceanis 320 1987 are built by Beneteau. That means shared dealer networks, common parts availability, and consistent build quality across the line. The choice between them is essentially a question of how much boat you need, not which brand you trust.