Site: Yamaha Motor Co., Ltd.
2500 Shingai, Iwata, Shizuoka 438

Date Visited: December 8, 1992

Report Author: D. Granville



D. Granville
V. Karbhari
J. McDermott


Mr. Kohtaro Horiuchi

Dir., Sr. General Manager, Marine Div.

Mr. Akira Kubota

Manager, Eng. Div., Marine Operations

Mr. Hisao Aono

Manager, Production Dept., Marine Operations

Mr. Takashi Motoyama

Assistant Manager, Horiuchi Lab

Mr. Osamu Hashimoto

Chief Engineer, Production Eng.Dept., Marine Operations

Mr. Masao Yokouchi

Assistant Manager, Production Eng.Dept., Marine Group


Yamaha developed human-powered and solar-powered racing boats for competition along with an America's Cup racing boat. The construction of the America's Cup boat is urethane paint, unidirectional carbon fibers/epoxy pre-preg and honeycomb core. They use low temperature cure pre-preg and vacuum bag molding methods on plywood tools. On the other hand, the construction of ocean-going boats is unidirectional T-glass epoxy, Kevlar woven cloth, and PVC foam. They use room temperature cure and vacuum bag molding methods, with reinforcement fibers laid up and impregnated by hand with resin on plywood tools. A new product is a remote-controlled agricultural helicopter sprayer.

Yamaha began working with composites in 1960 (boats). Yamaha instructs suppliers to satisfy resin/feedstock quality as specified by its engineers, and inspects these materials when received. It also has its own educational program that includes apprenticeship education and training in manufacturing methods, rendered by senior and junior engineers. Yamaha specializes in "one-off" custom designed boats and low-rate production boats. There is no automated equipment except for chopper gun and gel coat paint spraying equipment. They use glass fiber reinforced plastics mold for production boats and plywood tools for trials and "one- off" custom designed boats.


America's Cup yacht -- use of low temperature pre-preg in sandwich/skin construction on plywood tools with vacuum bags. Designed using "rule- based" design guide based on consensus hydrodynamic design by a technical committee composed of design experts from universities and industrial partners. Then "building simulation" is completed by fabricating sub-scale components and finite element materials (FEM) study and panel tests (small and large). Their NDE testing procedure is not fully developed.

Racing sculls are composed of two-ply graphite uni-tape, "Klegecell" foam and two-ply graphite uni-tape, fabricated manually. Their solar-powered one- man racing boat and human-powered racing boat are also fabricated manually.

They are currently marketing a radio-controlled helicopter for agricultural spraying applications called the R-50. The helicopter has a fuselage of 2655 mm, with a main rotor of 3070 mm diameter, and a 98 cc engine. The blades and body enclosure are fiberglass and layed-up by hand. Weight is 67 kg.


"Hobby-shop" type activity was displayed during the tour of the Yamaha plant. This is a factory for trials and "one-off" custom designed boats only. They have six factories for production of boats located throughout Japan (Shizuoka and other prefectures). When asked if this facility is also used to build custom or prototype composite parts/assemblies for Yamaha's other activities (motorcycle shrouds/enclosures) the answer was yes, but to a limited extent. This division mainly makes trials and "one-off" custom-designed boats where automation has no advantage since each boat is unique or made in small quantity. They make it a rule to have discussions with suppliers of composite feedstocks and resins beforehand, so that they can receive materials that have been altered according to specifications. Other than thermocouples, no processing feedback monitoring/control was observed, and they had only visual NDE capability. Yamaha's greatest cooperative effort is extensive design and modeling with Japan's technical universities and industry in support of the America's Cup effort. Yamaha uses a push-pull system for styrene emissions.


Booklets and Brochures:

"Invitation to Yamaha."

"Yamaha R-50."

"Yamaha Marine Line-Up," 1992.


Japan's First Challenge to America's Cup 1992, edited and produced by Shipping and Trade News, Published by Tokyo News Service, Ltd., Part 1, April 1991.

Published: April 1994; WTEC Hyper-Librarian