Carbon Park Avenue Convertible to Motorised Furling Boom
Maxspar has developed a new boom which can start life as a Park Avenue boom for a full batten mainsail and at a later date be easily transformed into a motorised furling boom — without the need to change the boom itself.
The transformation option comprises a carbon mandrel, an electric motor and the fitting of a second mount on the boom for the mandrel. This solution allows those who are undecided whether to install a Park Avenue Boom or a Furling Boom to first install the Park Avenue and then make the conversion to a motorised furling boom later.
The following photos show an example installation on the yacht Giannetti Star 64, on a Park Avenue boom later converted into a furling boom.
Park Avenue Boom
The Park Avenue boom is the optimal solution for offshore and bluewater racing. Its widened upper profile provides a true sail-shaping platform: the mainsail can be positioned precisely along the boom, reducing twist and maximising aerodynamic power across the full range of trim conditions. The result is a more controllable sail shape upwind and reaching, and a cleaner exit profile downwind.
Like our furling booms, the Park Avenue is built from pre-impregnated carbon and cured in our autoclave as a single piece — delivering the highest stiffness-to-weight ratio achievable in this class of spar. All fittings, vang attachment points and mainsheet sockets are designed and machined in-house around the specific sail plan of the yacht.
Carbon Furling Boom
A furling boom allows the mainsail to be furled onto a rolling bar inside the boom — rapidly reducing sail area using a hydraulic or electric motor. The aerodynamic form of the mainsail is the same as that of a traditional sail, with the roach chosen by the sailmaker — with no reduction in area compared to mast furling systems. The sail requires a specific layout of the battens to allow furling, and all accessories must meet technical specifications which we will indicate.
The boom section is composed of two parts: one a container for the mainsail, the other a structural reinforcement of the boom. The furling boom is manufactured from pre-impregnated carbon and cured as a single piece in a vacuum autoclave (see photo below) — producing a piece with reduced weight and maximum rigidity. We can produce furling booms up to maximum dimensions of 1250×960mm at the vang section, tapered at both ends — the ideal section for a 150ft yacht — for a maximum length of 23 metres, with boom weights ranging from 1,500 to 3,000 kg depending on the project specification.
Inside the boom there is a tube connected to a winding motor which allows the height of the mainsail to be adjusted in any position, optimising the relationship between sail area and sideslip. The mainsail, when furled inside the boom, is completely protected from the effects of the sun (see photos in the gallery below).
System Features
- Latest-generation mechanical reducers — 5 models: ø110 · ø140 · ø182 · ø280 · ø360 mm
- Motor housed inside the winding tube — simplified construction and assembly, with reduced overall weight
- Two-button operation for winding / unwinding, with optional remote control
- A P=30m / E=10m sail can be fully furled in under 2 minutes
- Mainsail fully protected from UV when furled inside the boom
- Suitable for yachts from 50ft to 150ft
This type of furling requires a hydraulic vang designed to support boom and sail. The mainsail should be manufactured according to our technical specifications. We recommend using an electric winch at the foot of the mast.
Furling Boom Reference List
Over 80ft
- Wally 83
- Wally 93
- Perini Navi 88
- Swan 90
- Nautor 115
60–80ft
- Swan 77
- Wally 60
- Vallicelli 70
- Felci 71
- Mylius 65
50–60ft
- Grand Soleil 50
- Vismara 50
- Frers 47
- Swan 48
- Solaris 47