Tender ship

A ship's tender, usually referred to as a tender, is a boat, or a larger ship used to service or support other boats or ships, generally by transporting people and/or supplies to and from shore or another ship. Smaller boats may also have tenders, usually called dinghies.

For a variety of reasons, it is not always advisable to try to tie a ship up at a dock; the weather or the sea might be rough, the time might be short, or the ship too large to fit. In such cases tenders provide the link from ship to shore, and may have a very busy schedule of back-and-forth trips while the ship is in port.

On cruise ships, lifeboat tenders do double duty, serving as tenders in day-to-day activities, but fully equipped to act as lifeboats in an emergency. They are generally carried on davits just above the promenade deck, and may at first glance appear to be regular lifeboats; but they are usually larger and better-equipped. Current lifeboat tender designs favor catamaran models, since they are less likely to roll in the calm to moderate conditions in which tenders are usually used. They typically carry up to 100 to 150 passengers and two to three crew members.

Before these ships were mass-produced, the main way to board a larger ship (mainly ocean liners) was to board a passenger tender. Passenger tenders remained based at their ports of registry, and when a ship came through the area, the tender would tie up with the ship and embark passengers on an elevated walkway. These vessels were larger, had a greater passenger capacity, and a broader sense of individuality in their respective companies than the more modern tenders seen today. Because of their increased size, lifeboats and life preservers were commonplace on board these ships (with two boats being the standard amount for an average tender).

Before the technologies that allow submarines and destroyers to operate independently matured by the latter half of the 20th century (and significantly during the Second World War), they were heavily dependent upon tenders to perform most maintenance and supply. Their hull classification symbols in the US Navy were, respectively, AS and AD, while general repair ships were AR. Naval tenders fell out of use during the late 20th century, as the speed and range of warships increased (reducing the need for advanced basing).

...
Wikipedia