Henry H. Hooyer, a graduate of the Nautical College at Amsterdam, Netherlands, began his seafaring career as a cadet on a passenger ship. He sailed on freighters and was employed for ten years by a large tanker company in various ranks. His first command was a coastal supply vessel that took him along the coast of West New Guinea and into the headhunting region. In 1960, Hooyer became harbor master at West New Guinea and did piloting at Hollandia, Sorong, and Muturi Oil Terminal. When West New Guinea became part of Indonesia in 1962, he left that part of the world to become harbor pilot at San Nicolas, Aruba, Netherlands Antilles.

In 1967, he accepted a two-year assignment as instructor at the newly opened Shiphandling Training Center at Grenoble, France, where a fleet of model tankers in the one to twenty-five scale is operated on an eight-acre lake. He then returned to real ships. He was a mooring master at Sidon, Lebanon; senior harbor pilot at Ras Tanura, Saudi Arabia; and marine advisor at Single Buoy Mooring Inc. at Monte Carlo, Monaco. Assignments took him to, among other places, Libya, Egypt, India, and the North Sea. He was back in Aruba in 1981 as docking master and training instructor for pilots, returning to Monaco at the termination of the three-year assignment. In 1993 Captain Hooyer was made a fellow of the Nautical Institute and is the author of Behavior and Handling of Ships.