The Boeing 929 Jetfoil is the name for a passenger-carrying waterjet-propelled hydrofoil design by Boeing.

Boeing began adapting many systems used in jet airplanes for hydrofoils. Robert Bateman led development. Boeing launched its first passenger-carrying waterjet-propelled hydrofoil in April 1974. It could carry from 167 to 400 passengers. It was based on the same technology pioneered by the patrol hydrofoil Tucumcari, and used some of the same technology used in the Pegasus class military patrol hydrofoils. Currently this product line is sold to the Japanese company Kawasaki Heavy Industries.

In 1979, the Royal Navy purchased a Boeing Jetfoil, HMS Speedy, to provide the Royal Navy with an opportunity to gain practical experience in the operation and support of a modern hydrofoil, to establish technical and performance characteristics, and to assess the capability of a hydrofoil in the Fishery Protection Squadron.

Boeing launched three Jetfoil 929-100 hydrofoils that were acquired in 1975 for service in the Hawaiian Islands, which was operated by a Honolulu-based operator Seaflite Inc. Seaflite operated 3 Boeing Jetfoils between 1975 to the company's demise in 1979. When the service ended the three hydrofoils were acquired by Far East Hydrofoil (now TurboJET) for service between Hong Kong and Macau. About two dozen Boeing Jetfoils saw service in Hong Kong-Macau, Japan, South Korea, the English Channel, the Canary Islands, the Korea Strait, Saudi Arabia and Indonesia.