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(civil engineering)
The act or process of floating a ship after only hull construction is completed; in some cases ships are not launched until after all construction is completed.
The process of transferring energy from a coaxial cable or transmission line to a waveguide.



In shipbuilding, launching is carried out either after the ship has been completely built or after completion of basic shipbuilding work, such as construction of the hull, mounting of the rudder, and installation of propellers. Launching by simple flotation (floating out) is used in building and repairing large-displacement ships in dry docks and floating docks. End and side launchings by gravity, that is, by sliding or rolling, are carried out from a slip or building berth on sliding ways or carriages that run on inclined tracks; these launching methods are used for ships of medium displacement.

End launching from a longitudinal building berth is usually carried out on ground ways located on both sides of the keel. Both ways extend underwater to a length calculated to make the ship float before it has traveled the entire length of the ways. Sliding ways are put under the ship before launching. Lubrication with grease, soap, mineral substances, paraffin, or petrolatum provides a low coefficient of friction between the runners of the sliding ways and the ground ways. The ship is launched stern first in order to avoid burying the end of the ship in water and to reduce the length of the run through water. Other means to reduce the length of this run include affixing braking boards to the sliding ways and throwing out anchors.

In side launching, four to ten ground ways are used. They may extend far into the water for floating-out launching or only to the water’s surface, or they may terminate several meters above the water. The list taken by the ship during side launching may be as great as 90°.

Provisions are made to prevent a spontaneous movement of the ship caused by gravity. They include special restraining devices made of cable, wood, or steel and launching triggers. If needed, the initial momentum for launching a ship can be supplied by a hydraulic winch, a tugboat, or levers. Mechanized launching is carried out with the aid of carriages, platforms with mechanical hoists, and loading cranes. Such launching is typical for lot building of small and medium-size ships. The launching of large ships is usually accompanied by a festive ceremony and a solemn ritual.


References in classic literature ?
The launching of the Sari proved easier than I con-templated.
If he succeeded in launching the boat, if he kept ahead of the second ice-run, if he did not get caught by some of the runs from the upper Yukon; if luck favored in all these essential particulars, as well as in a score of minor ones, they would reach Sixty Mile and be saved, if--and again the if--he had strength enough to land
The final task remained--the launching of the boat.
He started the engine, and with a wild burr of gas explosions the beautiful fabric darted down the launching ways and lifted into the air.
The boys--with the exception of Master Squeers, who, coming to his father's assistance, harassed the enemy in the rear--moved not, hand or foot; but Mrs Squeers, with many shrieks for aid, hung on to the tail of her partner's coat, and endeavoured to drag him from his infuriated adversary; while Miss Squeers, who had been peeping through the keyhole in expectation of a very different scene, darted in at the very beginning of the attack, and after launching a shower of inkstands at the usher's head, beat Nicholas to her heart's content; animating herself, at every blow, with the recollection of his having refused her proffered love, and thus imparting additional strength to an arm which (as she took after her mother in this respect) was, at no time, one of the weakest.
But, to bring this rapid sketch to a close, I will only add that a certain Hans Pfaal, of Rotterdam, launching himself in a balloon filled with a gas extracted from nitrogen, thirty-seven times lighter than hydrogen, reached the moon after a passage of nineteen hours.
And friend Murchison, with his chronometer in hand, his eye fixed on the needle, his finger on the electric apparatus, is counting the seconds preparatory to launching us into interplanetary space.
At first he tried the career of a professional agitator; going to Ireland he attempted to arouse the people against English tyranny by such devices as scattering copies of addresses from his window in Dublin or launching them in bottles in the Bristol Channel; but he was soon obliged to flee the country.
I was sure of launching the place in a very prosperous agricultural career, and of doubling the population, when once it had begun to work.
He was not therefore greatly pleased with this cold answer of his nephew; nor could he help launching forth into the praises of Sophia, and expressing some wonder that the heart of a young man could be impregnable to the force of such charms, unless it was guarded by some prior affection.
Veneering launching himself upon this trustee as his oldest friend (which makes seven, Twemlow thought), and confidentially retiring with him into the conservatory, it is understood that Veneering is his co-trustee, and that they are arranging about the fortune.
Instead, for the first time in more than 13,000 launchings since operations began at Wallops in 1945, the lightning itself took over the job.