Sea trial

Nobiskrug new ship Sabine Howaldt on sea trials in the Kiel Fjord in May 1958

Sea trials are fairly standardized using technical bulletins published by ITTC, SNAME, BMT, regulatory agencies or the owners. They involve demonstrations and tests of the ship's systems and performance.

Speed trial

In a speed trial the vessel is ballasted or loaded to a predetermined draft and the propulsion machinery is set to the contracted maximum service setting, usually some percentage of the machinery's maximum continuous rating (ex: 90% MCR). The ship's heading is adjusted to have the wind and tide as close to bow-on as possible. The vessel is allowed to come to speed and the speed is continuously recorded using differential GPS. The trial will be executed with different speeds including service (design) and maximum speed. The ship is then turned through 180° and the procedure is followed again. This reduces the impact of wind and tide. The final "Trials Speed" is determined by averaging all of the measured speeds during each of the runs. This process may be repeated in various sea states.

Crash stop

To test a crash stop, the vessel is ballasted or loaded to a predetermined draft and the propulsion machinery is set to the contracted maximum service setting, usually some percentage of the machinery's maximum continuous rating. The trial begins once the order to "Execute Crash Stop" is given. At this point the propulsion machinery is set to full-astern and the helm is put hard-over to either port or starboard. The speed, position and heading are continuously recorded using differential GPS. The final time to stop (i.e.: ship speed is 0 knots) track line, drift (distance traveled perpendicular to the original course) and advance (distance traveled along the original course line) are all calculated. The trial may be repeated at various starting speeds.

Endurance

During endurance trials the vessel is ballasted or loaded to a predetermined draft and the propulsion machinery is set to the contracted maximum service setting, usually some percentage of the machinery's maximum continuous rating. The fuel flow, exhaust and cooling water temperatures and ship's speed are all recorded.

Maneuvering trials

Maneuvering trials involve a number of trials to determine the maneuverability and directional stability of the ship may be conducted. These include a direct and reverse spiral manoeuvres, zig-zag, and lateral thruster use.^[1]

Seakeeping

Seakeeping trials were originally used exclusively for passenger ships, but are now used in a variety of vessels. They involve measurements of ship motions in various sea states, followed by a series of analyses to determine comfort levels, likelihood of sea sickness and hull damage. Trials are usually protracted in nature due to the unpredictability of finding the correct sea state, and the need to conduct the trials at various headings and speeds.^[2]

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Nobiskrug

Nobiskrug

Nobiskrug is a shipyard located on the Eider River in Rendsburg, Germany, specialized in building innovative, custom-made luxury superyachts.

Differential GPS

Differential GPS

Differential Global Positioning Systems (DGPSs) supplement and enhance the positional data available from global navigation satellite systems (GNSSs). A DGPS for GPS can increase accuracy by about a thousandfold, from approximately 15 metres (49 ft) to 1–3 centimetres.

Ship motions

Ship motions

Ship motions are defined by the six degrees of freedom that a ship, boat or any other craft can experience.

Sea state

Sea state

In oceanography, sea state is the general condition of the free surface on a large body of water—with respect to wind waves and swell—at a certain location and moment. A sea state is characterized by statistics, including the wave height, period, and spectrum. The sea state varies with time, as the wind and swell conditions change. The sea state can be assessed either by an experienced observer or by using instruments like weather buoys, wave radar or remote sensing satellites.

• RMS Lusitania – While steaming at high speeds, severe vibration was noted at the stern during her sea trials. This prompted her builder, John Brown & Company, to reinforce that area before acceptance by Cunard.^[3]
• SS Normandie – During sea trials, vibration was noted at the ship's stern. The stern was reinforced, accepted by her owners Compagnie Générale Transatlantique, and continued onto her maiden voyage. The vibration was severe enough to necessitate relocating Tourist Class passengers and some crew members with cabins near the affected area. The problem was subsequently resolved by changing her propellers to four-bladed ones from the original three-bladed ones.^[4][5]
• RMS Queen Elizabeth – At the start of World War II, it was decided that Queen Elizabeth was so vital to the war effort that she must not have her movements tracked by German spies operating in the Clydebank area. Therefore, an elaborate ruse was fabricated involving her sailing to Southampton to complete her fitting out.^[6] Another factor prompting Queen Elizabeth's departure was the necessity to clear the fitting out berth at the shipyard for the battleship HMS Duke of York,^[6] which was in need of its final fitting-out. Only the berth at John Brown could accommodate the King George V-class battleship's needs.
  One major factor that limited the ship's secret departure date was that there were only two spring tides that year that would see the water level high enough for Queen Elizabeth to leave the Clydebank shipyard,^[6] and German intelligence were aware of this fact. A minimal crew of four hundred were assigned for the trip; most were transferred from Aquitania for a short coastal voyage to Southampton.^[6] Parts were shipped to Southampton, and preparations were made to move the ship into the King George V graving dock when she arrived.^[6] The names of Brown's shipyard employees were booked to local hotels in Southampton to give a false trail of information and Captain John Townley was appointed as her first master. Townley had previously commanded Aquitania on one voyage, and several of Cunard's smaller vessels before that. Townley and his hastily signed on crew of four hundred Cunard personnel were told by a company representative before they left to pack for a voyage where they could be away from home for up to six months.^[7]
  By the beginning of March 1940, Queen Elizabeth was ready for her secret voyage. The Cunard colours were painted over with battleship grey, and on the morning of 3 March, Queen Elizabeth quietly left her moorings in the Clyde and proceeded out of the river to sail further down the coast, where she was met by the King's Messenger,^[6] who presented sealed orders directly to the captain. While waiting for the Messenger, the ship was refuelled; adjustments to the ship's compass and some final testing of equipment were also carried out before she sailed to her secret destination.
  Captain Townley discovered that he was to take the ship directly to New York in the then neutral United States without stopping, or even slowing to drop off the Southampton harbour pilot who had embarked on at Clydebank, and to maintain strict radio silence. Later that day, at the time when she was due to arrive at Southampton, the city was bombed by the Luftwaffe.^[6] After a zigzagged crossing taking six days to avoid German U-boats, Queen Elizabeth had still crossed the Atlantic at an average speed of 26 knots. In New York she found herself moored alongside both Queen Mary and the French Line's Normandie, the only time all three of the world's largest liners were berthed together.^[6] Captain Townley received two telegrams on his arrival, one from his wife congratulating him and the other from Queen Elizabeth thanking him for the vessel's safe delivery. The ship was then secured so that no one could board her without prior permission, including port officials.^[6]
• RMS Queen Mary 2 – Her trials were conducted over two periods, September 25–29, 2003 and November 7–11, 2003, each lasting four days at sea, shuttling between the islands of Belle-Ile and L'ile d'Yeu off the French coast. On board for each set of trials were 450 people, including engineers, technicians, owner and insurance company representatives, and crew.^[8]
• USS Thresher (SSN-593) – Lost during deep sea diving tests on April 10, 1963.

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RMS Lusitania

RMS Lusitania

RMS Lusitania was a British ocean liner that was launched by the Cunard Line in 1906 and that held the Blue Riband appellation for the fastest Atlantic crossing in 1908. It was briefly the world's largest passenger ship until the completion of the Mauretania three months later. She was sunk on her 202nd trans-Atlantic crossing, on 7 May 1915, by a German U-boat 11 miles (18 km) off the southern coast of Ireland, killing 1,198 passengers and crew.

John Brown & Company

John Brown & Company

John Brown and Company of Clydebank was a Scottish marine engineering and shipbuilding firm. It built many notable and world-famous ships including RMS Lusitania, RMS Aquitania, HMS Hood, HMS Repulse, RMS Queen Mary, RMS Queen Elizabeth and the Queen Elizabeth 2.

Cunard Line

Cunard Line

Cunard is a British shipping and cruise line based at Carnival House at Southampton, England, operated by Carnival UK and owned by Carnival Corporation & plc. Since 2011, Cunard and its three ships have been registered in Hamilton, Bermuda.

Compagnie Générale Transatlantique

Compagnie Générale Transatlantique

The Compagnie Générale Transatlantique, typically known overseas as the French Line, was a French shipping company. Established in 1855 by the brothers Émile and Issac Péreire under the name Compagnie Générale Maritime, the company was entrusted by the French government to transport mails to North America. In 1861, the name of the company was changed to Compagnie Générale Transatlantique. The company's first vessel, SS Washington, had its maiden voyage on 15 June 1864. After a period of trials and errors in the late 19th century, the company, under the direction of its presidents Jules Charles-Roux and John Dal Piaz, gained fame in the 1910s and 1930s with its prestigious ocean liners such as SS Paris, SS Île de France, and especially SS Normandie. Fragilized by the Second World War, the company regained its fame in 1962 with the famous SS France, which suffered major competition from air transport and was retired from service in 1974. In 1977, the company merged with the Compagnie des Messageries Maritimes to form the Compagnie Générale Maritime. Then, in 1996, the company Compagnie Générale Maritime merged to form the CMA CGM.

Cabin (ship)

Cabin (ship)

A cabin or berthing is an enclosed space generally on a ship or an aircraft. A cabin which protrudes above the level of a ship's deck may be referred to as a deckhouse.

RMS Queen Elizabeth

RMS Queen Elizabeth

The RMS Queen Elizabeth was an ocean liner operated by Cunard Line. With Queen Mary she provided weekly luxury liner service between Southampton in the United Kingdom and New York City in the United States, via Cherbourg in France.

HMS Duke of York (17)

HMS Duke of York (17)

HMS Duke of York was a King George V-class battleship of the Royal Navy. Laid down in May 1937, the ship was constructed by John Brown and Company at Clydebank, Scotland, and commissioned into the Royal Navy on 4 November 1941, subsequently seeing combat service during the Second World War.

King George V-class battleship (1939)

King George V-class battleship (1939)

The King George V-class battleships were the most modern British battleships in commission during the Second World War. Five ships of this class were built: HMS King George V, HMS Prince of Wales (1941), HMS Duke of York (1941), HMS Anson (1942) and HMS Howe (1942). The names honoured King George V, and his sons, Edward VIII, who had been Prince of Wales, and George VI who was Duke of York before ascending to the throne; the final two ships of the class were named for prominent 18th century admirals of the Royal Navy.

RMS Aquitania

RMS Aquitania

RMS Aquitania was a British ocean liner of the Cunard Line in service from 1914 to 1950. She was designed by Leonard Peskett and built by John Brown & Company in Clydebank, Scotland. She was launched on 21 April 1913 and sailed on her maiden voyage from Liverpool to New York on 30 May 1914. Aquitania was the third in Cunard Line's grand trio of express liners, preceded by RMS Mauretania and RMS Lusitania, and was the last surviving four-funnelled ocean liner. Shortly after Aquitania entered service, World War I broke out, during which she was first converted into an auxiliary cruiser before being used as a troop transport and a hospital ship, notably as part of the Dardanelles Campaign.

King George V Graving Dock

King George V Graving Dock

King George V Graving Dock, also known as No. 7 Dry Dock, is a former dry dock situated in Southampton's Western Docks. It was designed by F.E. Wentworth-Shields and constructed by John Mowlem & Company and Edmund Nuttall Sons & Company. It was formally opened by King George V and Queen Mary on 26 July 1933 although the final construction work was only complete the following year. At the time of construction it was the largest graving dock in the world, a status it retained for nearly thirty years.

King's Messenger

King's Messenger

The Corps of King's Messengers are couriers employed by the British Foreign, Commonwealth and Development Office (FCDO). They hand-carry secret and important documents to British embassies, high commissions, and consulates around the world. Many King’s Messengers were retired Army personnel. Messengers generally travel in plain clothes in business class on scheduled airlines with their consignment. The division's official name changes depending on the gender of the reigning monarch.

Luftwaffe

Luftwaffe

The Luftwaffe was the aerial-warfare branch of the German Wehrmacht before and during World War II. Germany's military air arms during World War I, the Luftstreitkräfte of the Imperial Army and the Marine-Fliegerabteilung of the Imperial Navy, had been disbanded in May 1920 in accordance with the terms of the 1919 Treaty of Versailles which banned Germany from having any air force.