The Nautor 50, also called the Swan 50 MS, is a Finnish sailboat that was designed by Sparkman & Stephens as a motorsailer and first built in 1976.^[1][2][3][4]

The design was built by Oy Nautor AB in Finland, from 1976 to 1978, with nine boats completed.^[1][2][5][6]

When production ended the moulds were sold to Siltala Yachts. That company modified the design and sold it as the Nauticat 52.^[1][2]

The Nautor 50 is a recreational keelboat, built predominantly of glassfibre, with wood trim. It has a masthead ketch rig, a raked stem, an angled transom, a skeg-mounted rudder controlled by a wheel and a fixed fin keel. It displaces 50,926 lb (23,100 kg) and carries 14,926 lb (6,770 kg) of lead ballast.^[1][2]

The boat has a draft of 5.58 ft (1.70 m) with the standard keel.^[1][2]

The boat is fitted with a British Perkins Engines diesel engine of 115 hp (86 kW). The fuel tank holds 470 U.S. gallons (1,800 L; 390 imp gal) and the fresh water tank has a capacity of 523 U.S. gallons (1,980 L; 435 imp gal).^[1][2]

The design has sleeping accommodation for nine people, with a double "V"-berth in the bow cabin, two mid cabins, each with two bunk beds, an U-shaped settee in the main salon and two aft cabins, one with a double berth on the port side and one with a single bunk on the port side. The galley is located on the starboard side just forward of the companionway ladder. The galley is C-shaped and is equipped with a three-burner stove, an ice box and a double sink. There are two heads, one just aft of the bow cabin on the port side and one on the starboard side in the aft cabin.^[1][2]

The design has a hull speed of 8.21 kn (15.20 km/h).^[1][2]

• List of sailing boat types