Edwin A. Link 1904-1981 by Martha Clark Revised by Jeanne Eichelberger

Ed Link's life was dominated by two vastly different mediums: air and water. His career was marked with innovative solutions to problems common in these environments. The early Link trainer, submersible decompression chamber, and lock-out submersibles all exemplify Link's ability to provide new answers to problems encountered by many other people. Ed's highly creative mind constantly pushed him to explore new interests, even while engrossed in other projects. As these interests developed and changed, so did his business career. Good timing, successful inventions, and a little luck provided Link with the financial means necessary to pursue new challenges. Working in the fields of aviation simulation, underwater archaeology, and ocean engineering, he made it possible for other people and companies to expand and complete the systems he began. Edwin Link stands as a pioneer, with the foresight to see the potentials of aviation and underwater engineering¾fields that could be fully developed only if solutions were found for seemingly overwhelming problems.

Edwin Albert Link, Jr., the youngest son of Katherine (Martin) and Edwin A. Link, Sr., was born on July 26, 1904, in Huntington, Indiana, where his father was connected with the Shaff Brothers Piano Company of Chicago. In 1910, when Ed was 5 years old, Edwin Link, Sr. bought the bankrupt Binghamton Automatic Music Corporation and moved the family to Binghamton, New York. Link, Sr. renamed his new enterprise the Link Piano and Organ Company, and enjoyed a reputation as a manufacturer of reasonably priced player pianos, nickelodeons, and theater organs. The mechanical aptitude of the youngest Link was undoubtedly influenced by his father's piano business. In school he had little use for most academic subjects, but showed great interest in anything of a mechanical nature. After 1918, when his parents separated, Link's education was characterized by short stays in several different schools: Rockford (III.) Training High School; Los Angeles Polytechnic High School; Bellefonte Academy in Pennsylvania; and the Lindsley Institute in West Virginia. The differences between these schools reflected the disputes between Link and his parents concerning the quality of his education and his future. In 1922 Ed Link moved back to Binghamton, and after one more try at Binghamton Central High School, started working for his father at the piano company. His developing skill in organ rebuilding and repair laid the basis for Link's eventual work with the flight trainer.

Ed Link's interest in flying was originally stimulated by news accounts of World War I. His first flight took place in Los Angeles in 1920. Although theoretically he was being taught to fly, Link was never allowed to touch the controls, and could only watch as the pilot put the airplane through a series of complicated maneuvers. Neither this experience, which was the accepted method of teaching, nor the high cost of flying could dampen Ed's enthusiasm. His parents did their best to dissuade him since most barnstormers were viewed as seedy and unreliable characters, but Ed continued to take lessons and practice in friends' airplanes. In 1926 he took his first solo flight, and by 1928 was able to convince his mother to help him buy an airplane¾the first Cessna Model AA. He had already received a limited rating as a pilot from the Department of Commerce and was ready to leave his job at the piano company to take on the responsibility of being a full-time pilot.

The time Link worked for his father was not wasted, for he gained a thorough understanding of the mechanisms used in building organs and the principles of compressed air. In 1924 he filed for his first patent for an invention which picked lint off player piano rolls. The basement of the shop afforded him the space he needed to work on another invention¾a machine that would make it easier to learn to fly.

Link's first aviation trainer was made from parts of an organ and used compressed air to provide the motion of an airplane in flight. Ed believed that learning to fly would be less traumatic and considerably less expensive if beginning students started in a trainer while they were still on the ground. It took one-and-a-half years of experimentation before Link felt that the controls of the trainer had a response similar to that of a moving airplane. On April 14, 1929, he filed for a patent, and shortly thereafter formed the Link Aeronautical Corp. in Binghamton to market the trainer.

Ed Link worked constantly, promoting the use of the trainer as an educational tool while continuing to improve it with additional instrumentation. The trainer found early acceptance in amusement parks as a coin-operated ride, but few people saw its potential for teaching flying. To this end, Ed Link organized the Link Flying School in 1930, featuring the Link Trainer as the core of the curriculum. He was so confident of its capabilities that the school offered its students a guaranteed learn-to-fly offer for $85. At first this unusual offer generated interest in the school, but as the Depression deepened, flying became a luxury few could afford.

Searching for alternatives to teaching, Link spent the early 1930s working at several small airports in towns near Binghamton. His work typically included acting as general manager of the airport, servicing airplanes, and doing any flying that might bring in extra money. In 1931 he married Marion Clayton, a reporter for a Binghamton newspaper, and she quickly took over many of the business aspects of Link's enterprises.

Another important person in Ed's career was Charles S. (Casey) Jones, a well-known aviator who maintained many connections with the military. In 1932, Jones' company, the J.V.W. Corp., became the exclusive sales representative for the Link Trainer. Despite these changes and the increasing sophistication of the trainer, the Depression continued to hamper Link's businesses, and he was forced to find new ways of selling aviation. The most successful of these was a changeable lighted sign which Link hung below his plane to advertise for local merchants. Promoting the “electric sky sign” meant extensive night flying and trips in bad weather, and so Ed became skilled at flying on instruments. His new ability was reflected in his constant tinkering with the trainer, and new models with advanced instrumentation were introduced.

By 1934 the aviation industry had become a recognized feature of American life and began to prosper. Link's fortunes followed suit, aided by events in the United States and the world which caused military personnel to recognize the potentials of the Link trainer for teaching instrument flight. The U.S. Army Air Corps, which had taken over air mail routes in February 1934 with disastrous results, placed an order for six fully-instrumented trainers. In 1935, Japan bought ten Link Trainers; four were sold to the Soviet Union, and orders were placed by many European nations. A new “C Series” Instrument Flying Trainer was introduced in 1936, and the “D Series, ” which was sold mainly to European air forces, was developed in 1937. By 1940 trainers had been shipped to over thirty-five countries around the world.

The rapid acceptance of Link Trainers and their continued development, due chiefly to the threat of war in Europe and Asia, made it necessary for Link to reorganize and expand his enterprises. In 1935 Link Aviation Devices, Inc., was established to manufacture trainers and other aviation instruments. Link Aeronautical Corp., situated at the Tri-Cities Airport in Endicott, New York, maintained the flight school, an airplane repair service, and operated charter flights. A Canadian plant was established in 1937 in Gananoque, Ontario, since British contracts specified that their trainers must be manufactured within the British Commonwealth.

During this time Link Trainers became increasingly sophisticated in instrumentation, the simulation of flight, and the ability of the instructor to monitor the progress of students. Many of the changes mirrored advances in design and instrumentation of military fighter planes. The first trainer to reflect the idiosyncrasies of a particular type of airplane was the AT-6-SNJ, which was introduced in the early 1940s. Prior to this, trainers had been modeled on a composite, general airplane rather than on a particular model. Although general-type trainers continued to be manufactured, the future development of military jets dictated that trainers simulate particular planes as closely as possible.

In addition to the rapidly expanding series of trainers produced by Link Aviation, Link also oversaw the development of specialized trainers and aviation instruments. Special-use trainers included the “Aquatrainer, ” a prototype which simulated a sea plane, but which was never developed; gunnery, radar, and automatic pilot trainers; and the Celestial Navigation Trainer (CNT) which was commissioned by Great Britain in 1939. The CNT, a bomber crew trainer, was designed with help from P.V.H. Weems, a noted authority on celestial navigation. Link Aviation also produced a bubble sextant, an octant, and other navigation aids.

At the end of World War II in 1945, Link was faced with cancellations of orders, complicated by a glut of surplus trainers on the market. His concern that this would occur was evident by 1942 when he attempted to prepare for it by developing new projects to diversify the company. Link tried to tap the enthusiasm of school children for aviation by developing a low-cost, general purpose trainer to be used by the School Link program. He also established a marine division to build boats and a portable, sectional canoe, called the Linkanoe.

The technology for building and designing trainers was changing rapidly, and it was hoped that these projects would fill the gap until a new line of Link Trainers could be engineered and introduced. Due to Link's early experience in his father's piano company, Link Trainers were based on pneumatic principles allowing them to move freely to approximate the motion of a moving airplane. After the war, one of Link Aviation's major competitors, Curtiss-Wright, developed an electronically-based, stationary trainer which relied on instruments to indicate movement. Link Aviation hurried to improve on this development since the electronic system showed major advantages over trainers using air pressure. The idea that trainers, or simulators, as they began to be called, should remain stationary was adhered to for a while, but eventually Link Aviation returned to the production of trainers which actually moved when instruments indicated movement. In the early 1950s, Link Aviation was buoyed by the acceptance of simulators by commercial airlines and an increase in military expenditures caused by the Korean War.

By the mid-1950s Link Aviation was experiencing new financial and managerial stability. For the first time, people other than Ed Link were contributing to the growth of the company and projects were developed in which he had no role at all. With the introduction of computers and electronic-based simulators, Link found that his creative work had become routine, while the business aspects were increasingly complicated. His interests began to follow other paths, and he spent more time away from Binghamton. In 1953, he stepped down as president of the company, and took the less active position of Chairman of the Board. Link believed that to ensure the survival of Link Aviation in an increasingly competitive market, he should merge the company with a larger, more diverse corporation. In 1954, he and his brother George sold Link Aviation to General Precision Equipment Corporation, a large holding company operating out of New York City. Although Link still maintained an active interest in some aspects of aviation, particularly air safety, he had become involved in an entirely new activity¾sailing and underwater exploration.

Ed Link's new career in underwater archaeology and engineering developed from his interests in sailing and skin diving. What began as informally organized expeditions to seek under-water treasure ultimately resulted in systematic archaeological procedures, discoveries of great historic value, and the invention of complex machinery to aid divers. The eastern coast of Florida and the Keys were dotted with undiscovered and long-forgotten shipwrecks. Of primary importance to the explorers were wrecks of the Spanish treasure fleets which had sailed yearly to bring New World booty back to Spain. The 1951 Looe expedition that captured Link's enthusiasm and imagination was one of the first in American waters, although underwater archaeological expeditions had been common in the Mediterranean for many years.

With the end of the hectic war years at Link Aviation, the Links turned to sailing in the Bahamas and Florida for relaxation. Once they were introduced to underwater exploration, their forty-three foot yawl, the Blue Heron, proved to be poorly designed and inadequately equipped for the rigors of underwater searching. In May 1952, the Links bought a converted shrimp trawler which they named Sea Diver. Using their new boat as a base, they spent many months in the early 1950s exploring southern waters. Their two sons, William, born in 1938, and Edwin Clayton, born in 1941, joined them whenever possible. Gradually their searches became more organized and concerned with historic detail. From seeking gold and a bronze cannon made from an alloy which included platinum, the Links and their friends turned to searching for objects of historic value. Instead of dynamiting wrecks to see what objects would be exposed, the searchers learned that the position of the wreck and its contents could be vital keys in determining its identity. Much of the emphasis on historic search methods resulted from the influence of Mendel Peterson, Naval Curator of the Smithsonian Institution. Ed Link's interest in mechanical devices led to his use of sophisticated navigation instruments and the design of other equipment to aid his explorations. Among his innovations were a shallow draft search boat named Reef Diver, an airlift which made it possible to move bottom sand carefully, and a magnetometer which, when towed behind the boat, indicated the presence of metal on the ocean bottom.

When Link Aviation, Inc. was sold to General Precision Equipment Corp. in 1954, Ed was free to undertake more extensive archaeological expeditions. The first of these was organized for the summer of 1955 and consisted of three parts: searching for the wreck of Columbus' Santa Maria off Haiti; exploring the Atlantic Ocean's Silver Shoals for the remains of the Spanish treasure ship, Nuestra Sennora de la Concepcion; and establishing the route that Columbus might have taken on reaching the New World.

Link's interest in Columbus was sparked by his discovery in 1953 of a sixteenth-century lombard from Burrows Cay in the Bahamas. While trying to establish the provenance of the ancient gun, the Links did extensive research on Christopher Columbus, hoping that the gun might have come from one of his ships. Although the lombard was discovered too far north to be connected with Columbus, the Links had become preoccupied with trying to verify the original landing place of Columbus and finding the lost Santa Maria. They spent the month of April 1955 in Cap-Haltien, Haiti, looking for the wreck of the Santa Maria and the village of Navidad which was established by Columbus after the ship was wrecked. The Links did discover a Columbian period anchor, but there was no way to establish conclusively that it came from the Santa Maria. No traces of the wreck itself were found. The second half of the Links' Columbus expedition occurred later that summer in the Bahamas when they attempted to establish the place where Columbus first landed in the New World. Using his airplane, on-site explorations, and translations from Columbus' journal, in addition to other literature and secondary sources on the subject, Link theorized that Columbus landed on the Caicos Islands, traveled through the Bahamas, and eventually reached Cuba. Ed Link's research, “A New Theory on Columbus's Voyage Through the Bahamas, ” was published in 1958 by the Smithsonian Institution.

May 1955 was spent in the Silver Shoals, a forty-mile area of dangerous coral reefs in the open ocean between Hispaniola and the Bahamas. The Links and their crew were searching for the remains of the Concepcion, a fabled treasure ship that had already been extensively salvaged by Sir William Phipps in 1687. Link stayed at the Silver Shoals for slightly over a month, supervising the use of the magnetometer and coordinating his divers, but they could find no trace of the Concepcion in the maze of coral. Ed concluded that Phipps had probably salvaged most of the Spanish treasure, and the remains were so encrusted with coral that they would never be found.

The Spanish treasure ship, “Nuestra Señora de la Concepcion”, was rediscovered in 1978 by Burt Webber and contained a magnificent amount of treasure, as well as many artifacts.

In 1956, the Links planned two expeditions, both of which were far more extensive than anything they had attempted before. In May and June, Sea Diver made a preliminary expedition to Port Royal, Jamaica, in conjunction with the Institute of Jamaica. Port Royal, which had been a bustling colonial city and pirate stronghold, was almost completely destroyed in 1692 by an earthquake and tidal wave. Two-thirds of the city slipped into the sandy bay and was eventually covered with several feet of silt. During this expedition some of the major landmarks of the old city were uncovered, allowing Link to begin conducting an accurate survey of the ruined section of Port Royal.

The Links were also invited by the American-Israel Society to explore some of the ports in Israel to determine if interesting underwater archaeological sites existed there. In the early fall they flew to Israel and viewed sites at Caesarea, Acre, and the Sea of Galilee. Caesarea, one of the major ports of the eastern Mediterranean during the early Roman Empire, was deemed especially interesting since it was not a natural harbor, but had been built up by Herod the Great. Ed was intrigued with the prospect of returning to Israel, but he knew that extensive plans would have to be made before such an expedition could be undertaken.

Several important changes occurred in 1957 which delayed the Israel expedition, but became the foundation for Link's future work in ocean engineering. Foremost among these were the design and construction of a new, larger boat which could cross the Atlantic. Ed now owned a boat made especially for underwater research and archaeology which he equipped with the most advanced instruments available. The boat, named Sea Diver II, was built in Quincy, Massachusetts, during 1957 and 1958 and promised to be one of the most carefully designed and well-equipped boats for any kind of diving expedition. Link had little time for diving during these years, however. In 1957, he ended his retirement and went back to work as President of General Precision Equipment Corp., a position he held until May 1959. The second expedition to Port Royal was postponed for lack of time to organize it properly, and the old Sea Diver was sold unexpectedly in March 1957. Among the projects that Link worked on while land-bound was the development of a combination diving-bell and decompression chamber which would allow divers to work on wrecks in deeper waters than was currently possible. This device, called a submersible decompression chamber (SDC), became the focal point of Ed Link's Man-in-Sea project, and took several years to be engineered and completed, but the original concept was developed during his work in New York City at General Precision Equipment Corp.

Sea Diver II was launched in April 1959, and her shakedown cruise and first expedition took place that summer at Port Royal, Jamaica. Again, Link classified the expedition as a preliminary one, but his work on the sunken city was far more extensive than during the 1956 expedition. Link was aided by a team of Navy divers, and the expedition was sponsored jointly by the Smithsonian Institution and the National Geographic Society. Before any diving occurred, Link and Capt. P.V.W. Weems (USN, Ret.) prepared a map of the submerged portion of the city by coordinating pre-1692 maps with the location of major underwater structures found during the previous expedition. They discovered that Port Royal did not just sink, but actually slid down the bottom slope of the ocean. Using a strong airlift to remove accumulations of silt and mud, the crew of Sea Diver found hundreds of artifacts. The contents of a seventeenth-century kitchen, a ship chandler's shop, a fifteenth-century swivel gun, and a watch made in Holland in 1686 which had stopped running when the earthquake struck were among the valuable artifacts recovered by the expedition. These discoveries barely touched the surface of the historic treasure that would be found at Port Royal. Link believed that the site was one of the most important historic finds for seventeenth-century artifacts. Work done later at Port Royal by Robert Marx would prove that Link's assessment was quite accurate.

By October, Link had returned to Florida after a brief stop off the Yucatan peninsula to re-equip Sea Diver II and prepare her for the Atlantic crossing and subsequent expedition to Caesarea, Israel. Before leaving for the Mediterranean, the Links stopped in Haiti to pick up the Columbian period anchor they had discovered in 1955, and had it transmitted to America for safekeeping. Sea Diver left Puerto Rico on May 11, 1960, and arrived in Israel about a month later. The expedition schedule called for diving at Caesarea during the summer months when the wind and waves died down. Unfortunately, bad weather plagued the Links, and after repeated trips to the shelter of the harbor at Haifa, they shifted the expedition to the Sea of Galilee. There the divers discovered the remains of a cargo of unused cooking pots approximately two thousand years old. They also located a large section of flat stone pavement which provided evidence that the Sea of Galilee has a higher shoreline now than it did in the past.

Link took the crew back to Caesarea in September for a final attempt on the site before he and his wife returned to New York for the winter. The weather cooperated, and they were able to view the great stones which were part of the breakwater that surrounded the artificial port. Other Roman artifacts which were excavated included Bronze coins, carved ivory, Roman glass, and a complete second century Roman amphora buried beneath a huge beam. One of the most important finds was a small commemorative medal, struck in the first or second century AD, which portrayed the harbor, thus substantiating many of the writings of Roman historians about Caesarea.

Sea Diver spent the winter at a fishing port in Israel. The Links returned in April 1961 to prepare for their next summer of underwater exploration. They planned to operate on a more relaxed schedule than their work at Caesarea had allowed. Instead of sponsoring a concentrated expedition to work on one site, Ed anticipated cruising through the Aegean to Greece, and diving at likely sites near the Aegean islands and along the coast of Greece. The Links, in cooperation with the Greek Department of Antiquities, oversaw preliminary dives near Athens and at Voulia which resulted in the recovery of many amphorae, and at Navarino Bay, the location of a sea battle between the Turks and the combined British, French, and Russian fleets. Eventually, trouble with suspicious Greek officials persuaded Link to change his plans and continue on to Italy that fall. A stop at Siracusa, Sicily, resulted in an agreement to dive with the Marchese Piero Gargallo, the honorary superintendent of antiquities for southeastern Sicily. The Links promised to return the following summer to dive on some important wrecks with him. Sea Diver eventually berthed in Monte Carlo near Jacques Cousteau's International Oceanographic Museum.

Ed's submersible decompression chamber (SDC), which had been started several years earlier, finally arrived in Monte Carlo in the spring of 1962. Its arrival signaled a gradual shift in Ed Link's interests. Although the SDC was originally designed to allow divers to work safely on deepwater wrecks, Link became intrigued with the advantages it offered to all divers. It would allow them a safe, comfortable place to decompress after a dive, and would be an aid to preventing two serious effects of deepwater diving: the bends and nitrogen narcosis. The bends are the result of the formation of bubbles in the blood-stream of a diver when he is coming back to the surface and, if not prevented, can cause paralysis or even death. Nitrogen narcosis is a state similar to drunkenness caused by the absorption of too much nitrogen in the body. The SDC would provide an artificial environment where the air pressure and gases could be carefully monitored and controlled to prevent these problems. The submersible decompression chamber became the cornerstone of Link's program to allow divers to lie and work in the ocean at depths of up to one thousand feet. His name for the program, “Man-in-Sea, ” conveys the optimism he held toward the future of underwater development.

During the winter of 1961-1962, while Link was back in the States, he began laying the groundwork for Man-in-Sea. He received a grant from the National Geographic Society to help establish the project, and planned a joint venture with Jacques Cousteau in Monaco to use both the SDC and an underwater home developed by Cousteau. When Link arrived in Monaco in March 1962, the planning continued, but was interrupted by his voyage to Sicily to dive with Marchese Gargallo. Marchese had selected two wrecks which looked promising, one at Marzamemi, and the other at Ognina. The Marzamemi wreck was laden with marble, later identified as an altar and other sections of a Byzantine church dating from around 600 AD. On days when it was too rough to dive, Link experimented with the SDC which had been placed in a cradle on the deck of Sea Diver. Preliminary work included installing cables, hoses, and a winch chain to move the SDC up and down. Link was finally able to descend in the decompression chamber and to begin coordinating a routine for its actual operation.

After a brief stop in the Lipari Islands, Sea Diver arrived back in Monaco in July. Unfortunately, it soon became obvious that Link and Cousteau would not be able to collaborate successfully, and each proceeded with his own project. Link and Sea Diver left Monaco for Villefranche-sur-Mer, headquarters of the U.S. Navy's Sixth Fleet. He had been in contact with Navy officials for several years, and had followed their diving experiments with great interest. Two of these projects were of particular concern: using a mixture of helium and oxygen, known as heliox, to replace the air normally breathed by divers; and developing standardized decompression tables for deep dives. Since both of these projects were directly related to Link's work, Navy personnel were interested in seeing his SDC operate successfully. They agreed to provide a doctor trained as a life-support specialist who would monitor the atmosphere in the SDC, a supply of helium, and the assistance of a Navy submarine rescue ship if necessary. The major preliminary dive occurred on August 28, 1962, when Ed remained in the SDC at a depth of sixty feet for eight hours. This was the first time that anyone had ever been completely saturated with the heliox mixture, and it paved the way for the important two-hundred-foot dive that took place in September. During this dive, Robert Stenuit spent twenty-six hours in the SDC at two hundred feet, and was prepared to stay longer, but the helium supply was suddenly reduced, and safety precautions indicated that Stenuit should begin decompression immediately. The two-hundred-foot dive was judged to be extremely successful: it proved that man could breathe heliox for a sustained period of time without any problems other than an inability to speak in a normal voice (helium causes the voice to become high and squeaky); and that man could live comfortably with the pressure found at the depth of two hundred feet. Link and his back-up scientists immediately began planning the next dive¾this one at four hundred feet.

Before the dive could take place, however, more experimentation concerning its possible effects was necessary, and modifications and advances in the SDC and other equipment would have to be made. Link envisioned executing the dive late in 1963, but he began the testing immediately. Using several batches of mice, and later a goat in the SDC, Link studied the response of the animals to extreme pressure and their subsequent decompression. He also began designing for the divers new underwater living quarters, more spacious and providing better protection from the cold than that of which the SDC was capable. The SDC would be used as an elevator between the underwater house and a new, more spacious deck decompression chamber (DDC) where the divers would decompress. These were the component parts of Link's Man-in-Sea project as he described it to the National Geographic Society research committee. With them, and the addition of a portable shelter to cover work areas on the ocean floor, man should be able to live and work for long periods of time at depths that were heretofore unthinkable.

Ed's plans for a leisurely cruise across the Atlantic in 1963 to search for a diving site either in Bermuda or off the coast of the United States were shattered by the sinking of the Thresher, a large U.S. nuclear-powered submarine, in April 1963. Devastated by the loss, and eager to prevent such an accident from occurring again, the Navy formed a committee, known as the Deep Submergence Systems Review Group (DSSRG) to study the accident. Link was asked to head the industrial and civilian specialists of the group. He quickly brought Sea Diver back across the Atlantic and docked her at the Washington Navy Yard while he attended meetings. This stay in Washington gave Link the opportunity to conduct further pressure research with mice, watch Navy operations in the dry-pressure chambers at the Experimental Diving Unit, and consult with leaders in the field at the DSSRG meetings. By the time Link finished his work for the DSSRG in January 1964, he had subjected the mice to a simulated depth of three thousand feet, and seen men live in the pressure found at the four-hundred-foot level without any problems. He was ready to head for the Navy Yard at Key West, and prepare for the four-hundred-foot dive in earnest.

Ed Link and other members of the Man-in-Sea group had finished designing the new equipment, and now made the necessary modifications on the SDC. Their new system included a special underwater dwelling that was submersible, portable, and inflatable, which was called by its acronym, SPID. This was joined by a similar transportable work area cover known as IGLOO. Link's plans called for the SPID to be anchored on the ocean floor, thus providing a warm, safe environment for the divers who would remain on the bottom until their work was completed. The SDC functioned as an elevator, bringing the divers to the site, providing additional supplies when needed, and eventually taking the divers to the deck decompression chamber for an extended decompression period when they finished the dive. The Man-in-Sea group prepared for the dive during the spring of 1964 at Key West along with the chosen divers, Robert Stenuit and Jon Lindbergh, son of Charles Lindbergh. That spring a dive location was found off Great Stirrup Cay in the Bahamas at 432 feet. With help from the Navy submarine tender Nahant, the longest, deepest dive ever attempted began on June 30, 1964. The divers spent forty-nine hours on the bottom, and ninety-two hours decompressing.

For Link, the success of the four-hundred-foot dive also pointed out some of the problems inherent with the system. In addition to the obvious need for re-machining and redesign of some of the equipment, more serious problems included the lack of suitable hoisting mechanisms, and the need for a more efficient means of handling the number of hoses and cables connecting the SDC and SPID to the mother ship for air exchange, electricity, and communication. Link began working on a hydraulic hoist to solve the first problem, and gradually his thinking veered toward a fully independent SDC, or submersible, to conquer the second.

While working on the design of these two projects, Link became involved in a new business venture that was a direct outgrowth of the four-hundred-foot dive. In the spring of 1965 the organization of a new company was announced: Ocean Systems, Inc., composed of Union Carbide Corp., General Precision, Inc., and Edwin Link. Many of the people who helped coordinate the four-hundred-foot dive took positions with the new company. Link preferred to become a consultant to Ocean Systems, which left him the freedom to continue living on Sea Diver and designing new equipment. Ocean Systems, Inc., continued the work established by the Stenuit-Lindergh dive, and in many ways it was the appropriate conclusion to Link's own Man-in-Sea program. Starting as a concept developed and organized by an individual, the work had so expanded in both scope and organization that it was fitting it should be carried on by a company. As chief ocean engineering adviser, Link supervised many modifications of the SPID-SDC system, even while he, as an individual, was becoming increasingly committed to the use of independently operated submersibles.

During the summer of 1965, Link helped coordinate the operation of two innovative submersibles: Alvin, owned by the Woods Hole Oceanographic Institute; and a small Cubmarine leased to Ocean Systems, Inc. This experience confirmed his ideas concerning the utility of the vehicles, and helped him to formulate plans for the submersible he decided to design. Most submersibles were similar to submarines, except smaller. The inside pressure was kept at surface levels which eliminated the need for decompression, but also confined passengers to the interior of the vessel. Link's proposals were based on his earlier work with the SDC which allowed divers to leave the chamber to perform whatever work was necessary. This concept was incorporated into the Perry-Link #4 (P-L#4) which was built by Perry Submarine Company in Florida. There were two separate compartments within the hull of P-L#4, joined by a hatch which could seal them completely apart. The diver's compartment functioned in a manner similar to the SDC, allowing the regulation of air pressure and heliox so that divers could actually leave the submersible. When the dive was completed, the divers returned to their compartment and began decompression immediately. The pilot's compartment stayed at surface pressure so that the pilot did not have to undergo decompression, and was free to leave the submersible when it returned to Sea Diver. P-L#4 was launched in January 1966 and, although it looked like many other submersibles, it was the first pressurized diver lock-out small submersible built. The little sub was renamed Deep Diver and ownership was changed to Ocean Systems, Inc. As soon as the sea trials were complete, Deep Diver began to revolutionize procedures for deep dives.

During the four years that Deep Diver was commissioned, she was used for contract work by Ocean Systems, Inc., and scientific work with Sea Diver. Most of the dives occurred in the clear water off the Bahamas, but contract work included dives in the Gulf Stream near Fort Lauderdale, Florida, and the Newfoundland Banks. Link supervised lock-out dives at 420 feet, twenty feet, and seven hundred feet, and observation dives to over one thousand feet, close to Deep Diver's depth limit of 1250 feet. Scientists were particularly impressed with the submersible, since it allowed them to view marine specimens in their natural environment. Those scientists who knew how to dive had the added benefit of retrieving their own specimens, instead of relying on inexact trawling procedures from the surface. Deep Diver continued to make dives until 1970, when a report from the Bureau of Ships indicated that her use would have to be severely restricted due to structural problems with the hull. The submersible was decommissioned, but Link had already begun the design work on a new submersible that was even more radical in concept than Deep Diver.

In 1969, Ed Link moved Sea Diver II to a deserted mining channel between Vero Beach and Fort Pierce, Florida. He purchased the land, which he named Link Port, to provide a permanent base of operations for Sea Diver, and intended to develop a research facility for marine science and ocean engineering. The following year, Link invited Harbor Branch Foundation

Harbor Branch Oceanographic Institution (current name).

In this stimulating environment, Link completed the preliminary plans for the new submersible that would replace Deep Diver. Even before the highly successful Deep Diver was decommissioned, he realized that improvements could be made on the design. The basic layout of the new submersible, named Johnson-Sea-Link, remained unchanged, with two separate compartments so that lockout dives could be performed. To make Johnson-Sea-Link lighter, an aluminum alloy and acrylic were used instead of steel, thus eliminating the heavy frame common to most submersibles. Component parts were designed to be easily removed and replaced so that trouble in one section would not force a great delay in diving operations. The streamlined look of Deep Diver was lost completely since Ed believed it would not have any appreciable effect at the slow speeds that the submersible traveled. In its place was a huge, transparent acrylic sphere which was the pilot/observer's compartment. A tubular aluminum frame held the diver's compartment, battery pods and other component parts. In appearance the submersible closely resembled the body of a helicopter. In its finished state, Johnson-Sea-Link weighed eighteen thousand pounds, and was capable of operating to three thousand feet while locking out divers at depths of up to fifteen hundred feet. She was launched in January 1971 and commissioned to the Smithsonian Institution. Johnson-Sea-Link proved to be a most innovative and successful submersible. In 1975 JohnsonSea-Link II was launched and was now owned and operated by Harbor Branch.

With the establishment of Harbor Branch as a major oceanographic and engineering research facility, Link remained busy providing innovative ideas for the many projects Harbor Branch Foundation sponsored. Unfortunately, one of the most important projects developed by Harbor Branch, CORD (Cabled Observation and Rescue Device), was the result of a personal tragedy which occurred in June 1973. His younger son, Edwin Clayton Link, was killed during a routine dive in Johnson-Sea-Link, when it became ensnared in the wreckage of an old destroyer off the coast of Florida. Clayton and another diver, Albert Stover, died before the submersible could be rescued. Link spent the next two years helping Harbor Branch develop rescue equipment. Used in conjunction with a boat on the surface called Sea Guardian, the unmanned CORD is equipped with television cameras, lights, and hydraulic-powered claws and cutters to enable it to free any trapped submersible. Even in the face of overwhelming tragedy, Ed Link's unique combination of humanity and mechanical genius pushed him further in his search to make the oceans accessible and safer for humans.

At the SUNY-Binghamton Commencement Exercises in the spring of 1981, Edwin Albert Link was presented with the honorary degree, Doctor of Science, honoris causa. Though he had been so honored in the past by several other institutions of higher learning, this was a special occasion, for it marked the first time that the State University of New York conferred honorary degrees. The citation which accompanied the degree was read at the ceremonies:

State University of New York

EDWIN ALBERT LINK

Inventor, industrialist, pioneer of the skies

and oceans, you have opened for

exploration the heights of the heavens

and the depths of the seas. The fruits of

your creative imagination are many: from

your first flight simulator, which placed

America in a paramount position in

aviation, to devices and vehicles which

facilitate deep-sea resource development

and underwater archaeology. You have

enabled humanity to stretch above and

beyond the limits of the known world,

into the unknowns of outer space and

hydrospace. You believe that the greatest

age of discovery for our planet lies

ahead, and your avionic, astronautic, and

oceanographic inventions have revealed a

continuum of new frontiers for our

future. For your contributions to science

and industry, the State University of New

York takes pride in conferring on you,

Binghamton's foremost native son, the

degree of Doctor of Science.

May 31, 1981

Ed Link lived only a few months longer. On Labor Day, September 7, 1981, he died in his sleep. Although Ed had developed a number of health problems and had been undergoing treatment for cancer, his friend Harvey Roehl, visiting the Links that summer, found the patient, not languishing in bed, but up and around, in good spirits and looking forward to attending a boat show with his new steamboat, his enthusiasm for trying out new things undampened. In his energy and originality and his love of the sea, Ed Link has been compared to Jacques Cousteau. The fact that he did not attain the same level of “stardom” probably has less to do with his talent and success than with an essentially shy nature and a dislike of staying put and being pigeonholed. Despite considerable wealth and formidable achievements, Ed saw himself essentially as just another one of the guys. True genius, coupled with true humility and generosity of spirit, earned loyalty and admiration for Ed Link from people of all ages and walks of life.