Design 176 – Selestra 51
15.5m' Cruising Ketch

176
Other Drawings:

Gen. Arr. (with Magnify Tool).
Interior Plan & Profile.
Deck Plan.
Sail Plan.

Specification
LOA 15.500 m 50' 10¼"
LWL 13.568 m 44' 6"
Beam 4.400 m 14' 5½"
Draft, deep keel 2.200 m 7' 2½"
Draft, stub keel, c/b up 1.400 m 4' 7"
Draft, stub keel, c/b down 2.720 m 8' 11"
Displacement on dwl 18100 kg 39,904 lbs
Ballast 7000 kg 15,432 lbs
I 18.125 m 59' 5½"
J 5.540 m 18' 2"
P 16.310 m 53' 6"
E 5.775 m 18' 11½"
Py 10.025 m 32' 10¾"
Ey 3.790 m 12' 5¼"
Mainsail 41.100 m² 507.0 ft²
100% foretriangle 50.200 m² 540.3 ft²
Mizzen 19.000 m² 204.5 ft²
135% Genoa 68.400 m² 736.3 ft²
Mizzen staysail 44.500 m² 479.0 ft²
Engine 81 kw 110 hp
EU Category A - Ocean
The Selestra 51 is the first of new range of powerful classic modern cruising yachts envisaged primarily for construction in aluminium alloy, taking full advantage of our long experience of both designing and building in this material. The designs would also be suitable for cold-moulded wood/epoxy construction.

In aluminium alloy the Selestra class is built on well-spaced fabricated ring frames, the principal web components for which can easily be CNC cut, with the flanges naturally formed without rolling. A typical frame for the Selestra 51 is shown below – a larger image is here.

176 Selestra 51

Longitudinal T-section stringers are fairly closely spaced, running through the frames and naturally formed on the job. This system provides and extremely strong substructure, with relatively small panel areas, and will result in a very fair hull, requiring a minimum of filling and fairing if the hull is to be painted.

Plating is in diagonal strips, typically about 400mm to 500mm (16" - 20") wide, which will lay naturally around the hull without rolling or wheeling, and with little edge fitting required.

The Selestra 51 features a comfortable and spacious interior layout, well suited to long passage-making and sea going conditions, but providing equally comfortable living in harbour or at anchor. Electrical and mechanical systems are clustered around the engine room for simplicity and convenience of maintenance and servicing.

Click the image below for a larger version, together with a profile view.

176 Selestra 51

There are two large well-appointed double cabins, each with two good wardrobes and ample lockers and storage. The master cabin aft has an en-suite WC with separate shower compartment; there is also room for a compact washing machine adjacent to the engine room. The forecabin shares a large WC and separate shower with the third twin-berth cabin to starboard.

The spacious deck saloon has a large dining settee to starboard and a smaller two-seater settee to port. There is a partition alongside the companionway to port, which helps to provide a secure descent from the cockpit to the saloon – outboard of this there is a small bar overhanging the galley counter top.

The galley is a step down from the deck saloon to port. It is an ideal sea-going galley, compact, convenient, and in an area of least movement in rough weather. The refrigerated compartment backs on to the engine room to give minimum runs of pipework from the compressor.

The navigation station is two steps down from the deck saloon to starboard; aft of that is the ship's office with the principal access to the engine room opposite.

The sail plan is a medium aspect conventional ketch rig, with fully-battened, slab-reefing main and mizzen and a roller-furling genoa. In-mast furling or in-boom furling on the main are among other options – though with the centreboard version it would be better to avoid in-mast furling because of the extra weight aloft. While it's perfectly possible to have a modern square-headed main (and mizzen), this would mean that there would not be a standing backstay for the main – which for a cruising yacht, possibly quite short-handed, is perhaps not ideal. In this conteet the mainmast could be keel-stepped – without much disturbance of the interior layout.

The deck plan shown is for the aft control cockpit. This features twin steering stations – though a single central steering arrangement is equally suitable. Winches and sail control lines are grouped around the control cockpit is the instrumentation. The main cockpit being free of winches and sail control, is arranged for comfortable seating with a permanent cockpit table – great for harbour use and day sailing and safe for less experienced guests. For long-distance cruising a second set of auto-pilot controls in the main cockpit would be advantageous.

There are other possibilities for the deck layout. Version 01 has the conventional arrangement of steering and control from the main cockpit and no second cockpit at all. Version 02 has a secondary, smaller, control cockpit immediately aft of the mizzen; in this version, the mizzen is moved 200mm ahead and the main boom shortened to give a slightly higher aspect sail (and a taller mast to provide the same mainsail area and a slightly increased foretriangle area)

Though not shown on the plans, we envisage davits aft to carry an RIB and outboard; inbuilt liferaft and lifebelt storage in the stern pulpit; and fender stowage rings in both the bow and stern pulpits.

For yachts from about 10m (33') up, aluminium alloy really comes into its own with the best strength/weight ratio of all materials apart from exotic fibres. It is lighter and cleaner to handle than steel and used correctly in the right grades it doesn't corrode in a marine environment. It doesn't require painting, unless that is preferred, which pretty well produces the ultimate in a maintenance-free hull.

It can be cut with normal woodworking machinery and power tools (table saw, bandsaw, circular saw, router etc.). And it can be filed and drilled with ease. It does require good welding techniques and the correct welding equipment – for yacht work, almost exclusively MiG welding is used. Other than that, no specialist machinery is generally required.

The detailed and accurate plans together with true step-by-step building instructions carry builders, professional and non-professional alike, through the building process simply and easily. And for larger boats particularly, they allow a managed build to be carried out very successfully. Plans are fully dimensioned; no scaling or lofting is required. The plans and instructions are practical, clear and detailed, containing everything required to build and complete the vessel. Where CNC cutting files are included, or available, they can be sent directly to a CNC facility as required. Professional technical support throughout the build, is available by email, via the forum or by regular mail. More plan info