In 1961, Ham the Chimp became the first living organism to make a suborbital flight. His reward was an apple. Our reward was clearing the final hurdle to place the first man in space, a historical first for the U.S. space program. As the program progressed, it overcame problems with capsule flotation collars, parachute suspension systems, and, of course, splashdowns.
The business of landing a spacecraft was precarious, at best, in 1959, when the United States was developing its first manned satellite. Initial requirements included the engineering predictions of velocities, lift, trajectories, and nameless other technical monstrosities.
Impact studies were conducted using Yorkshire pigs strapped into their own contour couches to determine the effects on human astronauts during land and water landings. The pigs were slammed into the ground at forces tanging from 38 to 58 gs before internal injuries were noted. These tests supported disparate conclusions: one, the spacecraft would have to be fitted with an air bag to cushion impact, and, two, the pigs withstood far more abuse than had been anticipated. The experts hoped the astronauts would prove as resilient if necessary.
With no experience, predicting with any certainty where a spacecraft would land was not easy. Consider the problem: launch a spacecraft out of the atmosphere at thousands of kilometers per hour, time the retro-rocket firing duration and force, slam back into the atmosphere at this controlled velocity, and then descend on parachutes from 23,000 meters to impact unceremoniously in the vague environment of the sea.
The first suborbital flight of a Mercury capsule carrying a living organism was launched on 31 January 1961 with Ham the Chimp on board. Ham’s 16.5-minute suborbital space flight was tame compared to the splashdown.
The Redstone rocket carrying Ham’s Mercury capsule built up more speed than predicted on reentry. This excess velocity, compounded by a few miscalculated seconds, caused the capsule to land 209 kilometers farther down range than was intended. It splashed down 97 kilometers from the nearest recovery ship, the USS Ellyson (DD- 454). Ham spent nearly three hours in the water, while the waves battered the spacecraft mercilessly. Meanwhile, the heat shield punched holes in the capsule, which had capsized and was taking on water. When a helicopter from the USS Donner (LSD-20) finally picked up Ham and the capsule, the spacecraft had shipped aboard 360 kilograms of water. The capsule and occupant were flown to the Donner, where the undaunted Ham was offered and promptly accepted an apple.
Navy Lieutenant Commander Alan B. Shepard Jr. was in line for the next ride just four months later.
Making Some Changes Before Friendship-7: Ham’s harrowing splashdown indicated that the final phase of the missions could prove more dangerous than the space flights themselves. Changes were made in the type of landing bag used to cushion the impact. The concept of overshooting the target took on a whole new significance, embracing the hazards of an extended recovery time and the problem of how to return the capsule and occupant quickly and safely to the Navy unit.
Navy frogmen were introduced to assist returning astronauts as part of an emergency rescue team. Planners debated methods of recovering the astronaut and capsule, arguing against ferrying the astronaut inside the capsule by helicopter. They discussed methods of leaving the capsule and the dangers of the craft taking on water. An Air Force aircraft was assigned to provide over-the-horizon communications.
Shepard, the first American astronaut, was launched in a suborbital flight from Cape Canaveral, Florida, at 0934 on 5 May 1961. The spacecraft impacted the water 15 minutes after liftoff, some 486 kilometers down range of the launch pad. He described the experience in We Seven (Simon and Schuster, 1962): “I braced myself in the couch for the impact, but it was not all that bad. It was a little abrupt, but no more severe than the jolt a Navy pilot gets when he is launched off the catapult of a carrier.” Initially, Shepard was concerned that the capsule might be taking on some water, and, as it took some time to right itself, he was afraid he might have to escape from a submerging capsule. That did not happen, but such a fear foreshadowed ominous things to come.
The Sinking of the Liberty Bell-7: During the next space flight, Virgil I. (Gus) Grissom followed virtually the same suborbital path as Shepard and splashed down only 4.8 kilometers from his target in the Atlantic. The recovery helicopter was standing by to pick up the astronaut and capsule (named the Liberty Bell) when his spacecraft’s hatch blew off for an unknown reason.
The capsule immediately began to take on water from the open hatchway. Grissom managed to escape quickly and swam away from the capsule. The helicopter pilot assumed Grissom’s pressure suit would keep him afloat so the pilot headed for the sinking capsule. The helicopter’s crew frantically snagged the recovery loop on top of the capsule as it sank out of sight, pulling the helicopter’s three wheels into the water. The helicopter was able to lift the capsule partially out of the water.
Seeing the spacecraft rise, Grissom assumed the crew would then lower a sling to him as they had practiced. To his surprise, the helicopter began to move away from him. As Grissom began to wave at the departing chopper he noticed he was taking on water, too. In his haste to leave the flooding spacecraft, he had not closed an air inlet port in his suit.
Grissom did not know that the helicopter pilot had exceeded his lifting weight and received a warning light that his aircraft was about to experience engine failure. He was attempting to leave the area with the ponderously heavy capsule to allow another helicopter to pick up Grissom. The pilot did not know that the astronaut was sinking, too. Finally out of options, the pilot cut the Liberty Bell loose, and it sank immediately in 1,400 meters of water.
Grissom struggled to stay afloat, as he angrily watched his capsule sink. He could clearly see three other choppers hovering around him, all kicking waves and spray in his face. The three helicopters hesitated, oblivious to Grissom’s plight and uncertain as to what to do next after this bizarre deviation from plans.
As Grissom gasped and kicked to stay afloat, he regretted the two rolls of dimes and other souvenirs he had stored in the leg of his space suit, which now weighed him down. Finally, a helicopter slowly moved in, dragging a sling, which Grissom managed to grab and put on backward in his haste and confusion. The helicopter dragged him some five meters through the water before finally hoisting him to safety and returning him to the USS Randolph (CVS-15).
If there was any irony left from such a combination of unlikely events, it came on inspection of the helicopter that had attempted to recover the spacecraft. Its engine warning light had malfunctioned. The helicopter probably could have recovered the spacecraft. The science of splashdowns was in for another detailed reassessment.
Flotation Collars and Overshooting: Barely seven months later, Marine Corps Lieutenant Colonel John H. Glenn Jr.’s flight became the first American attempt to orbit the earth. NASA hurried to review and buttress old procedures while developing new safeguards. These included the use of divers dispatched in the water immediately after the capsule’s splashdown. They would attach a flotation collar around the capsule to keep it from sinking even if it filled with water. And they would be there in the water with the astronaut to assist him if required. NASA even supplied a tiny inflatable life vest fastened to the front of the astronaut’s space suit.
John Glenn’s Friendship-7, the first American manned spacecraft to reenter from an orbital flight, splashed down just 11 kilometers from the recovery ship Noa (DD-841). Not taking any chances, Glenn remained in the Mercury capsule until it was hoisted safely on deck.
The next orbital flight, with Navy Lieutenant Scott Carpenter, would encounter yet another recovery hazard not yet confronted in manned space flight. Carpenter nearly ran out of maneuvering fuel as he aligned his spacecraft for reentry and his automatic retro-fire system failed to initiate, forcing him to activate it manually three seconds late. A peculiar combination of these two factors, the fact that the capsule was pointed 25° in the wrong direction, and a below-normal thrust from the retro-rockets caused his spacecraft to splash down 463 kilometers off target. When Carpenter hit the water he was completely out of communications range, and no aircraft or recovery ships were in sight.
While the world pondered his fate, Carpenter slid out of his spacecraft into a raft. The first recovery aircraft arrived on the scene nearly an hour later. Carpenter was joined by two Navy frogmen. As Carpenter bobbed on the ocean, he opened his survival rations and began to snack. The two swimmers declined the astronaut’s offer to join him.
Coincident with this almost cartoonish scene unfolding on the open sea, a debate flared between the Navy and Air Force over who was actually going to pick up the astronaut. The Air Force had an HU-16 amphibious aircraft circling the scene. But the USS Intrepid (CVS-11) had responsibility as the prime recovery ship, and she had dispatched her helicopters to make the pickup. The HU-16 was ordered not to land and recover the astronaut unless the helicopters from the Intrepid, some 167 kilometers away, could not. And so they waited: Carpenter snacked on his survival rations; the frogmen and spacecraft bobbed on the open sea; and the planes circled overhead. Nearly three hours after he had splashed down, Carpenter was finally picked up by a helicopter from the Intrepid.
Congress and Secretary of Defense Robert S. McNamara were not amused by the delay. The decision not to allow the HU-16 to pick up the astronaut convincingly insinuated an ongoing rivalry between the services in the recovery organization. The Navy commander of the recovery forces, Vice Admiral John L. Chew, defended his decision based on the risk of a possible breakup of the HU-16 in the choppy waters, while Air Force General Leighton I. Davis, DoD space flight manager, blamed the snafu on a lack of direct communication with the astronaut. By the time Navy Lieutenant Commander Walter Schirra flew on the next mission, these problems presumably were resolved.
So too were the problems of overshooting splashdown. Schirra missed the planned target by only 8 kilometers. The final flight of Mercury splashed down only 1.8 kilometers off target.
Gemini’s Unsinkable Molly Brown: In March 1965, Gus Grissom and Navy Lieutenant Commander John W. Young were scheduled to fly the first of the nation’s new two-man spacecraft, the Gemini. Grissom, not known as a man to mince words, immediately christened his spacecraft the Titanic, in reference to his sunken Liberty Bell. NASA refused to go along with such humor but later approved Molly Brown, in reference to Denver socialite Molly Brown, survivor of the real Titanic.
The Gemini spacecraft splashdown sequence would be slightly different than Mercury’s. The new spacecraft would descend vertically but before splashdown would become nearly horizontal, placing the astronauts in a near-sitting position before impact. This maneuver was accomplished by an adjustment of the parachute suspension, called a two-point suspension system. The mass of the capsule was such that it would float horizontally in the water, astronauts in a sitting position, with the doors up out of the water.
As Grissom and Young’s spacecraft began reentry, it was discovered that the calculations of lift predicted for the Gemini were slightly off, and they would fall somewhat short of the prime recovery area. Before impact and on schedule, Grissom activated the two-point suspension system. Neither pilot expected the violent forward pitch, and their helmets crashed into the Gemini’s windows, damaging both face plates but not injuring the astronauts.
Grissom was startled after splashdown when all he could see out his window was seawater. He quickly realized that the parachute was still attached to the spacecraft and was pulling it nose-first through the water. He carefully released the chute, and the Molly Brown's windows cleared.
The spacecraft impacted 84 kilometers away from the primary recovery ship, the USS Intrepid. But the Coast Guard cutter Diligence (WMEC-616) was only a few kilometers from the astronauts and dispatched a helicopter to the spacecraft.
Space sickness is a well-known affliction for spacefarers of the 1980s. In the early days of Gemini, however, it was old-fashioned seasickness. Young was all right, but Grissom was quite ill. The original plan, which Grissom had endorsed wholeheartedly before the flight, was to remain in the capsule until the Intrepid could pick it up. But as his discomfort mounted, Grissom fought the urge to crack the hatch and get some cool, sea air. With memories of the sinking Liberty Bell still fresh in his mind, he kept the hatch firmly closed until the Navy frogmen could affix the flotation collar. Finally, after an interminable 30-minute endurance test, the collar was attached, and Grissom cautiously opened his hatch to a fresh ocean breeze. The astronauts departed for the Intrepid in one of her helicopters rather than waiting for the ship to steam the 110 kilometers to the spacecraft.
The next two Gemini flights would be afflicted by the same short landings. Gemini IV was short by 80 kilometers because of the same vexing lift calculations that had plagued Gemini III. Gemini V landed 130 kilometers short after a computer programmer neglected to program a trivial point. He programmed the earth’s rotation rate at 360° per day whereas the actual figure is 360.98. The difference caused the extreme landing error, which would have been greater had astronaut Gordon Cooper not compensated with what little lift the Gemini could offer on the way down.
The next flight had a long duration mission and included a space rendezvous between Geminis VII and VI-A. Gemini VII would be launched first, and would remain in orbit 14 days, longer than any previous mission.
The chief worry on such long missions was the crew’s physical response to the sudden return to the earth’s gravity and to the stresses of reentry and splashdown. Gemini Vll’s astronauts, Air Force Major Frank Borman and Navy Lieutenant Commander James A. Lovell Jr., were warned that after two weeks in weightless space they would probably lose consciousness just as the spacecraft righted itself in the water after splashdown. As the capsule bobbed upright, Borman and Lovell looked at one another while Borman quipped drolly, “Well, now we’re supposed to pass out . . . you want to or not?” Clearly the stress of return to gravity and splashdown was not as great as some had believed it would be.
Gemini VIII’s flight would not be so routine. The flight was commanded by civilian test pilot Neil Armstrong, who was joined by Air Force Captain David R. Scott. The Gemini had just completed its seventh hour of flight when a thruster malfunctioned, sending the spacecraft into an uncontrollable spin. Nearly blacking out, the crew just managed to bring the capsule under control and execute an emergency reentry. The crew splashed down in the Pacific, 1,000 kilometers south of Yokosuka, Japan, shaken but safe.
They were on the other side of the earth from the planned splashdown position. But the by now refined cooperation between DoD and NASA enabled a virtually flawless response that included communications relays between Houston Mission Control, ships at sea, and the spacecraft during retro-fire. Recovery crews left Naha Air Base in Okinawa on first word of the emergency, even before splashdown, and had attached the flotation collar to the capsule within 45 minutes of impact in rough seas. Three hours after splashdown, the USS Leonard F. Mason (DD-852) hoisted the crew and their Gemini on deck. It was a remarkable, well-planned, and superbly executed response to what had only been a contingency plan a day before.
The most significant aspect of the remaining four Gemini flights was the lack of any unusual event during reentry and splashdown. The system had been refined and was working at near perfection.
Return From the Moon: All three American spacecraft had unique characteristics in the water. Mercury floated balanced with its blunt end down. Gemini floated with its doors upright, its ends parallel to the waterline. But the Apollo command module was balanced so that it was just as stable floating upside down in the water as right side up. To alleviate this problem, engineers installed air bags in the nose which flipped the capsule over into the upright position when inflated.
The Apollo command module was used in three programs: the Apollo moon program, as a shuttle craft to the Skylab space station, and, finally, in the single Apollo-Soyuz mission in 1975. Unlike Gemini, Apollo had no reentry programming problems, and the first mission splashed down within two kilometers of the planned impact point. The spacecraft landed nose down in the water, but the air bags righted it as planned.
By the time the first Apollo spacecraft (Apollo 8) departed for the moon, the process of predicting accurate reentry points was so well-defined that mission planners began to worry about the spacecraft actually striking one of the recovery ships. One mission planner recommended the recovery forces be located eight to ten kilometers away from the targeted point, on purpose.
Moon voyages had high reentry velocities (in comparison with earth orbit reentries) of some 36,000 kilometers per hour. This type of reentry required precise recovery plans and reentry profiles, quite different from those of earlier orbital spacecraft. Yet, these profiles were so well planned and executed that no Apollo crew required more than an hour for recovery except for Apollo 8, which landed in the predawn darkness and had to await daylight for pickup.
As recovery operations became more refined—after the rather laid-back recovery of Scott Carpenter—the end of Apollo moon missions were usually viewed by worldwide television audiences. The astronauts typically were greeted by the ever-present Navy frogmen with sterile clothing and breathing masks to protect the earth from whatever microorganisms they may have brought back from the moon. They were then taken to waiting quarantine vans, where the first several lunar crews remained in isolation for up to two weeks.
None of the Apollo missions experienced abnormal or otherwise unusual reentry or splashdowns, probably because of the experience gained during Mercury and Gemini. Similarly, the missions of Skylab and Apollo-Soyuz ended flawlessly.
The days of intentional manned splashdown recoveries are probably over. But the use of the techniques learned from NASA’s relationship with the Navy from 1961 to 1975 will certainly be used indefinitely to some extent on unmanned recoveries. These no-energy, highly refined techniques, bom of the earliest ideas of spaceflight, still have a promising future.
Source Notes:
Most of the information contained in the article was taken from the public record. Additional sources used in the preparation of this article were books included in the NASA historical series:
L. S. Swenson et al., This New Ocean—A History of Project Mercury (Washington, D. C.: NASA, U. S. Government Printing Office, 1966).
B. C. Hacker, and J. M., Grimwood, On The Shoulders of Titans—A History of Project Gemini (Washington, D. C.: NASA, U. S. Government Printing Office, 1977).
C. G. Brooks et al., Chariots for Apollo—A History of Manned Lunar Spacecraft (Washington, D. C.: NASA, U. S. Government Printing Office, 1962).
M. S. Carpenter et al., We Seven—By the Astronauts Themselves (New York: Simon and Schuster, 1962).
D. Baker, The History of Manned Space Flight (New York: Crown Publishers, 1981.
The author acknowledges assistance from the NASA History Office, Headquarters, Washington, D. C., and the Public Affairs Office, Kennedy Space Center, Florida.
Dennis Chamberland received a bachelor of science degree and a master’s degree from Oklahoma State University. He is a former naval officer who served as executive officer of the U. S. Pacific Fleet Headquarters Support Activity, Makalapa, and as Assistant for Data Analysis, CinCPacFlt. He is now a Safety Specialist with NASA at the Kennedy Space Center.
As I Recall . . . Touchdown of Aurora 7
By Vice Admiral John Louis Chew, U.S. Navy (Retired)
Vice Admiral Chew was Commander Project Mercury Recovery Force at Cape Canaveral in 1962. The following is an edited and abridged excerpt from the transcript of an oral history interview of Admiral Chew conducted for the Naval Institute by Dr. John T. Mason on 23 January 1973. This excerpt concentrates on the recovery of the Aurora 7.
Only hours after being launched into orbit on the second U.S. manned orbital flight from Cape Canaveral on 24 May 1962, Lieutenant Commander M. Scott Carpenter, U.S. Navy, the Aurora 7/Mercury-Atlas 7 astronaut, landed some 200 miles downrange in the Atlantic Ocean. Consequently, no rescue ship awaited him. But, by this time, the rubber raft had been developed, and he got out of the capsule and was perfectly safe, and the capsule was floating. NASA had set a limit for the amount of time he should stay in the water, and it was going to take the helicopters nearly the maximum allotted time to reach him.
The U.S. Air Force sea-air rescue squadrons, meanwhile, wanted permission to land HU-16 seaplanes in the open sea to pick up Carpenter. However, being the person in charge of the recovery program, I thought he was safe and I could get the helicopters there. Frankly, I believed the HU-16s could land without much trouble, but taking off in a heavy sea was a different story.
NASA’s time limit of three hours was about to be exceeded when the HSS-2 helicopters arrived on the scene. The crew picked up Carpenter, made sure he was alright, and delivered him to the USS Intrepid (CVS-11). His capsule was returned by the destroyer USS John R. Pierce (DD-753). Those crews had trained well and they were certainly “johnny-on-the-spot.” The only reason it took them so long during this particular recovery was that they had to travel so far downrange to reach Carpenter.
I arrived back in Norfolk, Virginia, and Vice Admiral Wallace M. Beakley, the former Seventh Fleet commander and current Deputy Commander in Chief Atlantic Fleet under Admiral Robert L. Dennison, sent for me and said, “Jack, you did absolutely right. You're not an aviator, but I agree with you and I am an aviator of some 40 years standing. You were right in not letting the HU-16s land.”
I replied, “Well, I’m glad to hear that, Admiral, because I’m going to have a battle.” And as I predicted, I ended up having a battle. Secretary of Defense Robert S. MacNamara sent for me and wanted to know why I had not allowed the Air Force HU-16s to land.
I went to Washington to explain my decision to MacNamara, and I obviously was supported by the Navy and Admiral Beakley. MacNamara listened and said, “Well, after all, he [Carpenter] is back safely. The Air Force doesn’t agree with you, but he’s the proof of the pudding.” Nothing more was said. Nevertheless, this was a tense time for me. I was criticized by some members of the press for allowing the recovery to proceed by helicopter, according to plan, instead of allowing the seaplanes to land. A fight developed in the Joint Chiefs of Staff (JCS) about the command arrangements for the recovery of future flights. The JCS resolved it by ordering me, as the Navy’s recovery commander, to report to the Air Force general at Patrick Air Force Base and the Department of Defense coordinator for all recovery operations. In the past, I had simply had to report recovery operations to NASA and the launch team.
I still thought my decision was correct and I had been vindicated, to a certain degree, by the Navy.
For a catalog containing summaries of approximately 150 oral histories in the Institute’s collection, send $3 to Director of Oral History, U.S. Naval Institute, Annapolis, Maryland 21402.
Ocean Versus Land Recovery
The Mercury spacecraft was a maze of complex systems, built to meet certain basic requirements: to provide life support and protection against an alien environment, to provide the astronaut with some primitive (by today’s standards) control over the vehicle, and to bring him back safely to earth. Its design was principally driven by rigid weight limitations.
Because of these weight restrictions, planners decided the spacecraft would not employ certain characteristics on its return to earth:
► It would not have braking rockets to slow its return and subsequent fall to earth.
► Unlike a generation of space vehicles to come, it would not return to earth on wings and land like an airplane.
These constraints left few options to consider for an unpowered descent.
In the early 1940s, German scientist Wemher von Braun seriously mused over the practical aspects and hard engineering of landing a spacecraft when he and his Peenemunde colleagues envisioned a modified, winged A-9 rocket that would land on a conventional runway. Yet, these ideas were based on technology unattainable at that time. In 1946, the more pragmatic British Interplanetary Society (paradoxically enough, with an eye on von Braun’s own working V-2) proposed a manned spacecraft they called the Megaroc, adapted from V-2 designs. The Megaroc’s cabin was designed to sit atop an enlarged V-2. The spacecraft would reenter the atmosphere and be lowered by parachute to the land or sea. This was the first serious design concept implementing a splashdown recovery.
The United States adopted this practical solution to landing a spacecraft in 1958 as the nation rushed to develop a manned satellite capability. Like Megaroc, it would have to conform to the uncompromising realities of a weight limitation on a no-energy return to the earth.
An at-sea landing was selected because of four primary considerations:
► Weight savings: An atmospheric braking heat shield would absorb most of the kinetic energy of the spacecraft on reentry, thus precluding the need for braking rockets.
► Design simplicity: A capsule design did not provide nearly as much vehicle lift as a winged design. Therefore, the spacecraft would literally land where gravity directed it, on a purely ballistic path.
► Reduced uncertainty: Since most of the earth’s surface is covered by water, an ocean landing was far easier to plan for in the infant science of space flight with its high velocities and untested systems. Targeting would eventually become fairly precise. But at first glance, it was far less risky to aim for an ocean than a tiny, controlled area of land. Also, in an emergency de-orbit the capsule was more likely to land in the ocean.
► Impact force reduction: A single 19.2-meter main parachute would slow the Mercury capsule to an impact velocity of 9.2 meters per second. This was regarded as too high for an impact on land. If the capsule were outfitted with an air bag, however, ocean landings were well within acceptable limits.
The Redstone and Atlas boosters were the only boosters available to Mercury. They lacked the power and precision of the Titan and Saturn classes to follow. Ultimately, it was thought splashdown recoveries would be technically uncomplicated, while preserving precious weight and booster propellants. After the problems were resolved, at-sea landings were so successful that they continued through the first 14 years of manned space flight. All would follow the example of Mercury; they would collectively land at sea, dangling from the end of a parachute—even the more advanced Gemini and Apollo vehicles.
NASA Versus DoD: In the waning days of the Eisenhower presidency, a key political battle was fought over who would manage the emerging Space Agency, the Department of Defense or a separate civilian structure. The decision was handed to a newly formed civilian agency, the National Aeronautics and Space Administration (NASA), on 1 October 1958. DoD was allowed to continue planning for its own manned space programs at a fraction of NASA’s budget, but these programs did not survive.
NASA’s reliance on DoD was to be significant. Because of the nature of worldwide communications, tracking, and recovery at sea, the Navy would play a primary role. NASA would immediately rely on DoD’s extensive, already defined, and polished infrastructure. The arrangement was delineated primarily in military terms and organization.
As NASA struggled to find its organizational identity in mid-1959, NASA and DoD established an informal agreement to select two positions from each organization to act as points of contact. They would ultimately coordinate assistance received from each DoD branch—not an easy task, in light of historical service parochialism.
All services would participate. The Navy would provide at-sea search and recovery operations; the Air Force would contribute support for pre-launch and launch activities; the Army would be primarily responsible for spacecraft tracking and worldwide communications; and, finally, the Marines and Coast Guard would provide recovery support as tasked.
This organization did not change significantly throughout the final moon mission, Skylab, and Apollo-Soyuz in July 1975, although it did require some refinement. The organization consisted of:
►DoD Manager of Manned Space Flight Support Operations (Air Force)
► Deputy DoD Manager (Air Force)
►Director of Launch Vehicles (Air Force)
► Commanders Task Forces, Atlantic and Pacific (Navy)
►Commanders Task Groups, Primary Landing Area Recovery Forces (Navy)
►Range Safety Officer (Air Force)
Once it was clearly established that the spacecraft would land at sea and how it would land, NASA began preliminary, in-house plans for using Atlantic Fleet recovery units. When it took these plans to the Pentagon in the summer of 1960, Navy officials informed them that their plans would require “virtually the deployment of the whole Atlantic fleet” and a single recovery mission could well cost more than the entire Mercury program. NASA reluctantly regrouped and scaled back its early expectations.
— Dennis Chamberland