Supporting the “The Right Stuff”: Looking Back at the Navy Medical Department and the Mercury Space Program Part IV

By André B. Sobocinski, historian, U.S. Navy Bureau of Medicine and Surgery


Part IV: Bioastronautics and Medical Recovery


It was a strange and exciting sensation. And yet it was so mild and easy—much like the rides we had experienced in our trainers—that it somehow seemed very familiar. I felt as if I had experienced the whole thing before….Nothing could possibly simulate in every detail the real thing that I was going through at that moment, and I tried very hard to figure out all of the sensations and to pin them down in my mind in words which I could use later. I knew that the people back on the ground—the engineers, doctors and psychiatrists—would be very curious about how I was affected by each sensation and that they would ask me quite a lot of questions when I got back.

~Alan Shepard, We Seven

On May 5, 1961, Alan Shepard rocketed into history aboard his Freedom 7 capsule. The flight was the culmination of three-years of extensive and rigorous preparations for the then uncharted journey into space. The inaugural manned space flight also marked a new phase of the Mercury program—medical monitoring and recovery.

Part IV--Shepard inside Training Capsule--Courtesy of NASA
Alan Shepard inside trainer capsule prior to take-off. The Mercury space capsules were every bit rocket-powered laboratories. Inside each capsule the astronaut was connected to a host biosensors that telemetered data to aeromedical monitors below. In case of medical emergency, monitors could abruptly terminate the spaceflight. Courtesy of NASA Johnson Space Center Collection

Medical monitoring of spaceflights was first proposed by Dr. Stanley White, of the Mercury Space Task Group. In a memorandum dated October 1959, White emphasized the importance of tracking the health and well-being of the astronaut during flight and that the data collected could be used for future post-flight research.

Within each Mercury capsule the astronaut was attached to an assortment of sensors that tracked their heart rates, respiration, body temperature, blood pressure and telemetrically related the data to the ground stations. Navy, Army and Air Force medical personnel serving as aeromedical monitors made clinical assessments based on the incoming data and, if necessary, would determine whether the mission needed to be suddenly terminated.

Just as the astronauts had done previously, the aeromedical monitors underwent an extensive training program. From October through December 1960, monitors became acquainted with the astronauts, their training program, EKG procedures, environmental systems, the full-pressure suit, biosensors and other monitoring equipment, and received up-to-date briefings on the Mercury Project. During the spaceflights, the monitors were assigned to 16 tracking and monitoring stations located across the globe.

Part IV--Recovery of Freedom 7--Courtesy of NASA
The Project Mercury “Medical Recovery” operation was designed by Capt. Ashton Graybiel, MC, USN, of the U.S. Naval School of Aviation Medicine. Graybiel’s plan guaranteed that wherever the returning astronaut landed they would be recovered and given needed medical attention within three hours. Here we see the trajectory of Alan Shepard’s historic flight on May 5, 1961. Courtesy of NASA Johnson Space Center Collection

The other vital medical component of Project Mercury was the recovery mission. Capt. Ashton Graybiel, director of research, U.S. Navy School of Aviation Medicine, designed a medical recovery mission to ensure that the returning astronauts received needed and timely medical attention. Physicians designated to take part in recovery and post-flight check-up would pay special attention to the effects of high acceleration, weightlessness, rapid deceleration, and disorientation.

Three Air Force and one Navy medical facility (U.S. Naval Hospital Yokosuka) were designated to serve as “Project Mercury recovery support hospitals.”

The Navy was the designated lead for the recovery operation. Per Graybiel’s proposal, medical personnel were stationed aboard destroyers, dock landing ships (LSDs), aircraft carriers and at key shore points around the globe. Because of the distribution of these components the returning astronaut was guaranteed medical attention within three hours of landing.

Graybiel’s plan was tested by Mercury’s inaugural flight in May 1961. After a 15-minute suborbital flight, Shepard’s capsule parachuted down just over 300 miles southeast of Cape Canaveral.  A Sikorsky helicopter retrieved Shepard and delivered him to the Essex-class aircraft carrier USS Lake Champlain (CV-39) where medical personnel and media anxiously awaited. Navy physician Capt. (later Rear Adm.) Robert Laning who performed the post-mission check-up later recalled, “It was as complete as it could be without X-rays, including a neurological examination.  Of course, we had those facilities available in sick bay.  If he had been injured, we would have determined that when he got off the helicopter.”

Shepard’s launch in 1961 was followed by five more Mercury flights. Due to an atrial fibrillation, astronaut Deke Slayton was the only Mercury astronaut not to take part in spaceflight (Slayton was later cleared to fly during the Apollo Project).

Collectively, the Mercury astronauts logged two days and six hours in space. Without question Project Mercury was a resounding success, even though everything about it—i.e, training, planning and research—could be called experimental. However, without a little ingenuity and imagination as well as some of the “right stuff” there would be no Gemini Project, Apollo moon mission or Skylab. The Space Race would have been a foregone and the United States would have lost.


This is the final part of our four part series “The Right Stuff”:  Looking Back at the Navy Medical Department and the Mercury Space Program.

Previous installments of “Supporting the “The Right Stuff”:  Looking Back at the Navy Medical Department and the Mercury Space Program”:

Part I: The Johnsville Human Centrifuge

Part II: The Naval School of Aviation Medicine and the Human Disorientation Device

Part III: The Mercury Seven Visit Naval Medical Research Institute