A support yacht, sometimes called a shadow vessel, is a specialised yacht designed to carry equipment and operational infrastructure that support a larger primary yacht. 

Rather than combining hospitality and operations in one vessel, a support yacht separates those roles. The primary yacht remains focused on guest comfort, while the support vessel carries equipment such as helicopters, tenders, submersibles and expedition vehicles. 

This separation allows yacht programs to operate more complex equipment without compromising guest spaces. 

The purpose of a support yacht is to provide the operational capability required for complex yacht programs. 

Activities such as helicopter operations, diving programs, submersible exploration and large tender deployment require space, fuel systems, workshops and specialised crew. 

A support vessel carries this equipment and provides the engineering platform required to operate it safely. 

Support yachts are used to transport and operate equipment that expands what a yacht program can do. 

Typical uses include: 

• helicopter and hangar operations 
   

• submersible exploration 
   

• diving programs and decompression chambers 
   

• expedition logistics 
   

• transport, launch and recovery of large tenders and vehicles 

• hospital and/or first aid capabilities 

• Multi-sport court requirements (e.g. padel, pickle ball, basketball, etc.) 

They also provide workshops and technical spaces that allow equipment to be maintained during long voyages. 

Support yachts are designed to carry equipment that would otherwise occupy significant space on the primary yacht. 

Typical equipment includes: 

Aircraft 

• helicopters 

• aviation fuel systems 

Watercraft 

• large tenders 

• landing craft 

• chase boats 

Exploration equipment 

• submersibles 

• dive centres 

• research equipment 

• fishing equipment 

Vehicles 

• expedition vehicles 

• utility vehicles 

Operational infrastructure 

• workshops 

• spare parts storage 

• additional fuel 

Many modern vessels, including SHADOWCAT platforms, are engineered specifically to support these systems. 

Catamarans are often used for support yachts because their twin-hull architecture offers several operational advantages. 

Compared with a monohull of similar length, a catamaran provides more deck space, greater stability and improved operational efficiency. 

For these reasons many support vessels — including SHADOWCAT platforms designed with Incat Crowther naval architecture — use catamaran designs.