Everything you never knew you wanted to know about the Mercury Project
Pressure suit
From RixWiki
The Mercury pressure suit, popularly referred to as a space suit acted as a backup to the pressure vessel of the spacecraft. Pressure suits had been under development for high altitude flight since the early 1930s. Wiley Post was the first pilot to wear a pressure suit during a flight.
Contents |
B.F. Goodrich Contract
The contract to produce the Mercury pressure suits was awarded to B. F. Goodrich in July 1959, the David Clark company, and International Latex Corporation also bid unsucessfully. Goodrich had a long history of pressure suit development. Russell Colley, a Goodrich engineer had designed Wiley Post's pressure suit. Goodrich had developed a series of pressure suits for the U.S. Navy. The latest, the Mark IV, became the basis for the design of the Mercury suit.
The original contract called for the fabrication of 21 suits and spare parts at a total cost of $98,000. Russell Colley was the chief engineer for the project.
Each Mercury astronaut was provided with three individually tailored pressure suits, one for training, one for flight, and one as a spare.
 NASA.S61-00239 |
 NASA.S61-02733 |
Photo S61-00239 shows a photo of Grissom, Glenn and Shepard "in front of" a Mercury Redstone. This photo probably dates to when they were named as the three candidates for the first manned suborbital flight.
Photo S61-02733 displays some of the pressure suit components including gloves, boots, and a helmet. The date of this photo was given as 28 July 1961 in the NASA description, however, based on other photos with similar caption dates, and images numbers which are clearly of the pre-launch activities for the MR-3 flight, this appears to a pre-flight photo of Alan Shepard's suit.
Major components of the pressure suit
The pressure garment
The suit, in conjunction with the helmet, when the visor was closed, provided an airtight environment. As such it provided a backup for the pressure vessel. The garment had four layers from the inside out:
- A long-john like undergarment which provided comfort to the astronaut. Some portions had waffle-weave patches to lift the outer layers away from the skin to provide relief at pressure points and ensure that oxygen could flow between the suit and the astronaut's body..
- A double-wall vulcanized-nylon layer provided for air circulation and cooling. The inner wall was perforated to allow the wearers skin to breathe.
- A neoprene coated nylon layer made the suit air-tight.
- The outer covering was nylon aluminized for heat resistance.
The ECS suit circuit provided pressurized oxygen which entered the suit through a connector at the waist. The oxygen circulated throughout the suit, and exited through a connector from the helmet to be reprocessed by the ECS. Layers 2 and 3 covered the astronaut completely except for the hands and the head. The boots were put on over the neoprene coated nylon layer.
The suits were individually tailored to each astronaut. B. F. Goodrich made body molds of each astronaut by dressing him in long underwear, and then covering him with brown paper tape, and cutting the resultant body mold to remove it once dry.
Helmet
The helmet accounted for about half of the $5,000 cost for each suit. Molds of the astronaut's heads were made by Alice King Chatham. Cushioning leather covered helmet liners, called "lombards" after their inventor Charles Lombard, were made using these head molds as patterns. The outer shell of the helmet was fiberglass, and the faceplate was plexiglass.
The helmet incorporated a pneumatic seal which made the entire suit air-tight when the faceplate was closed. Pressure for this seal was provided by a gas bottle which is visible in photo S61-02733 above. The bottle was connected to a hose which entered the left side of the helmet.
Vocal communication between the astronaut and the ground was provided for by headphones and microphones within the helmet. Connections between these and the spacecraft communications system was via a connector on the right rear of the helmet.
Boots
Many photos show the astronauts in military boots, which might have been colored white or silver, the photo introducing this article shows John Glenn, and Deke Slayton wearing such white colored boots. These were worn during training, and do not accurately represent what the astronauts wore in flight.
The actual flight boots were lightweight, much like those worn by racing drivers today. They were silver-colored like the suit itself which had neoprene rubber "socks" to ensure that the suit was airtight. See photos Intro-2, AS-1, and AS-12 for better representations of the actual flight boots.
The suit worn by Gordon Cooper on the last Mercury flight had the "boots" as an integral part of the suit itself.
Mercury Suit Evolution
The suit and its related equipment evolved during the program to improve the comfort and mobility of the astronaut as knowledge was gained. There were two major revisions of the suit design, the first revision came as a result of experiences gained during [Al Shepard]]'s MR-3 flight. There were relatively minor changes for the next four flights. The need to allow the astronaut to comfortably endure a much longer mission led to more changes for Gordo Cooper's MA-9 mission.
Changes after MR-3
Shepard had some difficulty in bending his wrists. This led to a redesign of the way the gloves attached. In Shepard's suit the gloves zipped on to the ends of the sleeves. For [Grissom]'s and subsequent suits a new twist-lock fitting with nylon sealed ball bearings was used to attach the gloves.
Another change was the hero's medal a convex mirror worn on the astronaut's chest which reflected the instrument panel and allowed the pilot observer camera to serve as a backup for the instrument observer camera. This was also worn by Glenn and Carpenter. After Grissom's near drowning at the end of MR-4 a mini-life vest was added to the survival kit. This was worn under the hero's medal. Schirra wore it in the same position, although without the hero's medal which was no longer considered necessary.
Changes for MA-9
Gordon Cooper's suit for the MA-9 mission incorporated several changes, primarily to make the suit more comfortable for the 22-orbit, one-day plus mission.
The boots of Cooper's suit were integral to the outer suit, replacing the separate lace-up boots worn by earlier astronauts. The shoulder construction was different, the segmented shoulders so visible in the earlier suits were replaced by loosely fitting smooth panels. His gloves were newly designed. The pneumatic faceplate seal was replaced by a mechanical seal, eliminating the need for the pressure bottle and hose. His helmet also carried updated microphones and an oral thermometer, previous flights had used a rectal thermometer to monitor the astronaut's temperature.
Photo galleries
The careful scholar will note that the dates given for NASA photographs are sometimes suspect. Rather than being the date the photo was taken, it might be the date on which the photo was released for publication, or the date of the flight with which the photo is associated. Sometimes the date can be just plain wrong because of an invalid assumption (just because a photo is of John Glenn doesn't mean that the photo date relates to the MA-6 flight) or a mistake on the part of the caption writer.
With the above in mind, we will now look at photos of the Mercury astronauts in their space suits in the order in which they flew.
Alan Shepard
Shepard training
 Photo G60-02665 |
 Photo S61-00220 |
 Photo USF.61-mr3-033 |
Photo G60-02665 showing Alan Shepard wearing the personal parachute is said to have been taken on February 1, 1961.
Photo S61-00220 is a better view of Shepard in his pressure suit. The date on this photo is April 20, 1961. Note that the 3x4 array of round objects which appear over his right hand do not seem to appear in subsequent photographs.
Photo Photo USF.61-mr3-033 shows Shepard in spacecraft 7 during a full countdown rehearsal for the MR-3 mission.
Shepard MR-3
 Photo S61-02755 |
 Photo KSC-71P-0267 |
 Photo S61-02757 |
 Photo S61-02766 |
 Photo S61-02767 |
 Photo S61-02775 |
 Photo S61-02785 |
 Photo S61-02547 |
 Photo S61-02792 |
 Photo S61-02794 |
 Photo S61-02796 |
 Photo S61-03651 |
 Photo S61-03645 |
 Photo USF.61-mr3-109 |
 Photo S88-31374 |
 Photo S61-02727 |
 Photo S88-31380 |
 Photo S88-31382 |
The next photos show the process of dressing and preparing Shepard for MR-3. Photo S61-02755 shows the undergarment which was worn under the pressure suit. Note the waffle-weave sections outlined in black.
Photo KSC-71P-0267 shows the undergarment peeking out from the still unclosed main zipper. Photo S61-02757 shows the zipper closed.
Photo S61-02766 shows a close-up view of Shepard from the chest up, with good details of the helmet with the faceplate closed. Note that the frame of the faceplate seems to be wider than used for subsequent flights. S61-02775 is a similar photo with the faceplate open.
Photos S61-02767 shows Shepard undergoing a pressure leak test of the suit. Note the white hose which appears to be under pressure. I beleive that this is the hose which connects the pressurization bottle for the faceplate seal to the helmet. The bottle itself seems to be placed in a niche next to the contour couch. The same hose is prominent in photo S61-02766 which we have just described. In fact photo S61-02766 seems to have been taken during the pressure test as well, and then rotated to show the astronaut in a vertical position.
Photo S61-02785 shows the atronaut relaxing in the transfer van on the way to the launch pad.
The next series of photos shows Shepard's insertion into spacecraft 7. In photo S61-02547 Shepard peers into one of the capsule's porthole windows. As he approaches the hatch in photo S61-02792 we have a good left quarter rear shot showing the parachute harness. Photo S61-02794, showing Shepard talking to Grissom with John Glenn visible in the background, affords a view of the zipper attachments for the gloves which were unique to Shepard's suit, the suit pressure gauge on the astronaut's right wrist, the zipper up the left arm, the construction of the shoulders of the suit. Also visible is the connector for the faceplate pressurization hose low on the left side of the helmet, and the communications cable hanging from the right side of the helmet. The details on the faceplate, gloves, and harness are also of interest in this photo.
Photo S61-02796 is taken from a low rear angle and provides a rare glimpse of the back of the legs and boots, as well as the sole of the right boot.
Photo S61-03651, Photo S61-03645
Photo USF.61-mr3-109 shows Shepard "installed" in spacecraft 7, of course this photo is rotated 90° clockwise, the astronaut should be shown on his back. Notice the routing of the faceplate seal pressurization hose.
Photo S88-31374
Finally Photos S61-02727, Photo S88-31380, and S88-31382 show Shepard in his spacesuit on board the U.S.S. Lake Champlain after his recovery on the MR-3 flight.
Gus Grissom
Grissom Training
 Photo S88-55873 |
 Photo S61-01490 |
 Photo G61-00490 |
 Photo G61-00499 |
 Photo S64-36909 |
 Photo NASA.S61-03893 |
 Photo NASA.S61-04037 |
 Photo S61-02839 |
Photo Photo S88-55873 is an official portrait of Gus Grissom in his pressure suit. Photo S61-01490 was taken or released on 3 April 1961 is captioned "Astronaut Virgil Grissom photographed in the new Mercury Space Suit, holding his helmet."
Photos G61-00490 and G61-00499 show Gus Grissom in his pressure suit before participating in a centrifuge test. The NASA descriptions date these two photos as July 21, 1961, but this is the date of the MR-4 flight, so these photos are actually of an unknown date prior to the flight.
The official caption of photo S64-36909 also describes this as the "new Mercury space suit" and only says that this photo was taking during "training activities at the Florida space center."
Photo S61-02839 shows Grissom being suited up for a simulation prior to MR-4.
Photo NASA.S61-03893 shows Grissom during egress training while S61-04037 was taken during life raft training
Photo S61-02839 was taken while Gus was suiting up for a simulation run.
Grissom MR-4
 Photo S61-02845 |
 Photo S88-55875 |
 Photo S64-36915 |
 Photo S61-02888 |
 Photo 61-MR4-76 |
 NASA.S61-02882 |
 NASA.S61-02881 |
 Photo S61-02889 |
 Photo USF.61-mr4-077 |
 Photo S61-02894 |
Photo S61-02845 is said to be Grissom just before the MR-4 flight, however the image number would indicate that it was actually taken two days earlier when the flight was scrubbed. Another thing that makes this photo questionable is that the gloves seem to have the old-style zipper closure, perhaps this was Grissoms training suit and it had not been upgraded.
Photos S88-55875, and S64-36915 were taken during suiting up before the scrubbed attempt at MR-4.These photos show the new glove attachment design.
Photos S61-02888, 61-MR4-76, NASA.S61-02882 and S61-02881 show the insertion sequence before the scrubbed attempt.Photo 61-MR4-76 gives a very clear view of the new glove wrist bearings, as well as the heroes medal.
Photo S61-02889 shows Grissom approaching the Redstone launcher. Some details of the back of the harness are visible, but this photo is more dramatic than useful as a reference.
Photo USF.61-mr4-077 shows his insertion into spacecraft 11, Libery Bell 7 before his flight.
In photo S61-02894 we see Grissom on-board the USS Randolph after his mission.
John Glenn
Glenn training
 Photo G60-02424 |
 Photo M61-00150 |
 Photo S62-00246 |
 Photo S62-00249 |
Photo G60-02424 shows John Glenn being fitted for his space suit for the MA-6 flight. However, the date of this photo is said to be 12 December 1960 12 December 1960 which was over a year before his flight. Notice the early zipper style glove attachments which belie the fact that this was not taken near the time of MA-6.
Photo M61-00150 is said to be from 4 April 1961 4 April 1961, again this seems to have the old glove connections.
Photo S62-00246, taken during a fitting in pre-flight training, clearly shows the newer glove connections. A close up of the twist lock mechanism is shown in Photo S62-00249 which seems to be from the same session.
Glenn MA-6
 Photo S64-14854 |
 Photo S62-00460 |
 Photo S62-00371 |
 Photo S62-00957 |
 Photo S62-00961 |
 Photo S62-00965 |
 Photo S62-00993 |
 Photo S62-00994 |
 Photo S62-01000 |
 Photo S64-14843 |
 Photo S64-14848 |
 Photo S62-00222 |
 Photo S63-01207 |
 Photo S62-00302 |
 Photo S62-00303 |
 Photo S62-00304 |
Photo S64-14854 shows Glenn examining a sketch of the "nose" art for Friendship 7. Photo S62-00460 shows him with Cece Bibby the artist who painted the names on Glenn's craft as well as Aurora 7 and Sigma 7.
Photo S62-00371 is captioned as being Glenn's insertion for MA-6, as is S62-00957. Photo S62-00961 is in the same sequence judging by the image number. I suspect that these are more likely to be a practice session, due to the dearth of pad crew.
Photo S62-00965 is a close-up of Glenn. Notice the details of the connector for the outlet hose which connects the helmet to environmental control system. Also this shows the protective cover over the faceplate which was removed prior to flight. In some photos, such as S62-00371, appear to show ventilation holes in the top of the helmet, these appear to have actually been features of this protective cover. Note also the connection of the communication system cable on the rear right side of the helmet and the snap attachment for the "turtle neck" which connects the outer layer of the pressure garment to the helmet. This is also a good view of the heroes medal with the mini life vest underneath which was added after Gus Grissom's swim after MR-3.
Photo S62-00993 is captioned as a practice insertion. Glenn appears to be wearing the protective overshoes over his flight boots. Photo S62-00994 is the next picture in this sequence.
Photo S62-01000 gives a view of the lacing on the back of the gloves, as well as the battery holder for the fingertip lights.
Photos S64-14843, and S64-14848.jpg show Glenn during the suit-up sequence on launch day. Photos S62-00222, Image:NASA.S62-00330.jpg, NASA.S62-00377.jpg, and NASA.S62-00379.jpg show him leaving crew quarters on his way to the pad.
Photo S63-01207 is captioned as Glenn's insertion on launch day.
Photos S62-00302, S62-00303, and S62-00304 are photos of Glenn during the MA-6 flight taken by the pilot observer camera
Scott Carpenter
Carpenter training
 S64-36908 |
 S61-03510 |
 S61-03513 |
 S61-03522 |
 S62-00120 |
 S62-01381 |
 S62-01383 |
 MJ-000280 |
Photo S64-36908 is an official portrait of Carpenter in his pressure suit at an unspecified time during training in FLorida. Photo S61-03510 shows Carpenter before a simulated mission at the cape. Photos S61-03513, S61-03522 show him during a suiting exercise. The caption information on photo S62-00120, indicates that this photo was released on January 15, 1961 which means that this photo is most likely from the time when Carpenter was serving as John Glenn's backup for MA-6. Although S62-01381, and S62-01383 have a release date of March 16, 1962, after Glenn's flight, it may still be from the MA-6 preparations. Photo MJ-000280, again the date is unknown, shows Carpenter in a Mercury spacecraft on the pad.
Carpenter MA-7
 S64-14870 |
 S65-24622 |
 S65-24623 |
 S65-24624 |
 S62-04044 |
 S62-03907 |
 S62-02846 |
 S62-04047 |
 S62-04027 |
 S62-04058 |
 S62-04057 |
 SCVideo-1 |
Photos S64-14870, S65-24622, S65-24623, and S65-24624 show Carpenter being suited in an exercise prior to the MA-7 flight. Note the protective overshoes which are quite visible in S65-24623. Photo S62-04044 is of Carpenter walking out to be taken to the launch pad for MA-7. Note that he is wearing protective overshoes over his flight boots. Photo S62-03907 shows Carpenter looking into Aurora 7 prior to his insertion. Photo S62-02846 shows Carpenter's insertion into spacecraft 18, and S62-04047 is captioned as showing him in the spacecraft prior to launch.
Photos S62-04027, S62-04058, and S62-04057 were taken on the USS Intrepid after the MA-7 flight.
Photo SCVideo-1 is from a video of the pre-flight activities for MA-7 and shows a close-up of the left side of Carpenter's helmet.
