Message 3623, Jul 28, 2001
Hi John, This is a somewhat complicated subject you reference, as I shall explain. The MC-4 and MC-4A suits were the last expression of the so-called mechanical (or capstan) partial pressure suit developed by the Air Force until the TLSS program developed new avenues of inquiry in the mid 80s.
In the period from about 1946 through 1948 the David Clark Company produced versions of Dr. Henry's original mechanical (capstan) partial pressure suit (prototype developed in about 1946) in custom sizes for flight test pilots such as Yeager, et al.
In about 1948, the David Clark Company produced the T-1 suit (the first 'operational' partial pressure suit) for flight test and high altitude fighter test operations pilots in 12 standard sizes. By 1953 this suit was in use by fighter pilots in routine high altitude fighter operational missions.
The T-1 suit, one of the very first production capstan suits, used a 5-to-1 pressure constricting ratio, had no chest bladder, included both a pressure garment and an anti-G function, and was intended purely as a "get-me-down" emergency decompression suit. It provided about 6 to 8 minutes of protection only, at an altitude of about 65,000 feet. Interestingly, the T-1 suit was tested in hypobaric chambers to simulated altitudes of about 106,000 feet, where it safely provided the emergency pressurisation needed for a quick descent to lower altitudes.
The S-2 suit, evolved from the T-1 suit in the 1953-54 period, was similar to the T-1, but lacked the anti-G system, had no chest bladder, and was intended principally for used by bomber (SAC) crews who did not need protection against the forces encountered in ACM type flight (but who also needed the emergency decompression protection afforded by the T-1). 12 standard sizes for bomber aircrew were produced. Historical records state that the S-2 suit was used routinely with the K-1 partial pressure helmet assembly.
The S-4 suit (1955) was a modified S-2 suit that incorporated no chest bladder or anti-G system, but featured an abdominal bladder (specifically for use by individuals who had weak inguinal rings). It was also used alternately by bomber crews, with the S-2.
The MC-1 series suits (next along the development trail and introduced about 1956) was a modified S-2 suit that added breathing bladders to chest and abdominal torso sections of the suit to reduce the work of breathing and that also featured smaller arm & shoulder capstan systems; it was the first capstan suit designed specifically to permit somewhat extended flight at higher altitudes and was produced in 12 standard sizes for both fighter and bomber crews. The MC-1 suit included specially designed pressure gloves, as well as what were termed "anti-pinch" bladders beneath the capstans (to reduce friction and prevent skin abrasion). Historical documentation again specifies that the MC-1 type suits were used with "either the K-1 or MB-5 helmets".
The MC-3 (1957) and MC-4 (1958) suits were designed to provide extended high altitude operation, and both included a full-torso bladder to reduce effort of breathing at altitude. The MC-3 had a horizontal shoulder zipper, sewn breaklines, no anti-G system, used height/weight sizing criteria, and was utilised in bomber and recon aircraft; it was also manufactured, in 12 standardised sizes, by David Clark Company. It is noted in documents that this suit was principally used with the MA-2 helmet assembly, for which the primary system contractor was ILC of Dover.
In 1958 the MC-3A was introduced, which was a modified MC-3 with vertical shoulder lacing and adjustable break lines. David Clark and Berger Brothers were the primary contracting manufacturers. The MA-2 helmet (ILC) was specified for use with the MC-3A partial pressure suit.
In late 1958/early 1959 the MC-4 capstan partial pressure suit was introduced, which featured vertical lacing, adjustable break lines, an anti-G bladder system. It was used with the MG-1 pressure gloves and MA-2 helmet assembly (ILC). Shortly thereafter, the final refinement, known as the MC-4A partial pressure capstan suit was introduced (principally for fighter operations use) and remained in use until about 1964. This suit was a modified MC-4 suit, incorporating height/weight fitment criteria for fighter cockpit requirements, and an anti-G suit assembly. It is specified in historical documentation again that the MC-3 and MC-4 series suits were used with both the MA-2 and MB-5 helmets, as well as with the MA-3 (Bill Jack) helmet. (Use of the MC-3 series and MC-4 series suits continued in operational use until about 1964, as noted above).
The early K-1 helmet (the so-called "split-shell" K-1) was used with both the T-1 and initially with the early S-2 suit. Later, the K-1 helmet was improved with the addition of a one-piece fiberglass shell that had anti-lift helmet constraint cable attachments externally located, bilaterally, on the helmet shell. The final K-1 shell had these attachment points moved internally, to the inner, lower rim of the improved one-piece green K-1 shell on both sides. The improved (single external fiberglass shell) K-1 was used most frequently with the later S-2 production suits.
Whereas the K-1 series helmets were used with the early suits (the T-1, S-2, and MC-1 suits), the MC-3 and MC-4 series suits used the newer, improved helmet designated the MA-2 assembly, for the most part, although it is noted that they were also used with the MB-5 helmet. The MA-2 external fiberglass shell was of one-piece construction (like the last K-1 shell), but was painted white. The MB-5 helmet assembly was quite similar to the K-1 helmet and was used mainly by SAC crews with the S-2, MC-1, and MC-3/MC-4 suits. By 1959 records indicate that the standard USAF capstan pressure suits in use were the MC-3 and MC-4 series suits, routinely used with the MA-2 helmet assembly and MB-5 helmet assemblies.
Among the distinctive differences notable between the T-1, S-2, and later suits were variant lacing patterns, necessitated by the functional intent and design parameters of the suits (i.e. pressure suit or pressure suit and anti-G system combinations). All of the mechanical or capstan partial pressure suits were uncomfortable, due to the fact that they had to be snug fitting even in the normal unpressurised mode. They were also warm and were usually worn over light cotton inner underwear. Further, they were intended as an undergarment to be worn beneath the external flight suit and any other outer protective clothing, such as anti-exposure suits. A special inner ventilation garment could be also be worn. A major departure from the capstan type partial pressure suit was the introduction of bladder type partial pressure suits in the early to mid-60s, such as the CSU-4/P series. These suits did not use capstan systems to achieve high-altitude protection. The principle in use in the CSU-4/P type  garment was due to be further developed in coming years into such systems as the TLSS project equipment. Successful experience with the CSU-4/P concept also resulted in the David Clark suits used in the Space Shuttle protective "Launch-Entry" suits, initially introduced in about 1987, which employed bladder type compression of the CSU-4/P principle in combination with a full-pressure helmet and an integrated anti-exposure overassembly to provide protection.
Today capstan or mechanical type partial pressure suits are no longer used actively by the US Air Force, although suits of this specific type are still in use by various foreign nations (examples are the former "Warsaw Pact Powers" and the People's Republic of China). They bear startling resemblance to the USAF capstan partial pressure suits of the 50s and early 60s (and were most likely copied directly from the American design). This is all general background information that may be helpful, for your purposes, to be aware of.
Coincidentally, after the late 1950s, SAC crews were no longer routinely required to wear partial pressure suits on operational missions due to the fact that low-altitude nuclear penetration was by that time the mandated nuclear mission profile, necessitated by the deployment of improved anti-aircraft missile systems throughout the Warsaw Pact nations that could easily strike down high flying bombers. Fighter pilots continued to wear the capstan partial pressure suits into the early 60s and for special missions (U-2 & TR-1), although gradually the highest altitude missions (strat recon, SR-71 type) were being by that time flown with the newer full pressure suits that had come into production in the early 60s. In view of the above historical documentation references, your MB-5 helmet and MC-4 suit could have been and probably were used together as a properly matched set and the time frame would likely have been in the late 1950s/early 60s. I hope this information has been useful and helpful to you in your museum display project.
Cheers, DocBoink

Message 3622, Jul 27, 2001
Hi, Got a question for the group, I'm trying to assemble a representitive example of a US partial Pressure suit for a museum display. I recently picked up a MC-4 suit, along with a MB-5 partial pressure helmet that I'd like to use as the suit is large enough for the manniquin I have available. I also have a K-1 along with a MC-1 suit that I know was issued together but it's too small for the manniquin. I'm familiar with the K-1, MC-1, C-1 bottle/reg assy as a "proper" combo, but I'm having trouble finding any info on timeframe/application on either the MC-4 suit or the MB-5 helmet. The helmet appears to be a K-1 with a different mike and comm plug ( the short hood, earphone assy's and green outer shell appear to be the same as a K-1, however, it has a M-55/AIC green mic with a U 93A/U plug on the comm wire and the fitting or strain relief on where the wire enters the helmet is different than on a K-1) I'm fairly sure that the helmet and suit were flown together as they came from a militaria dealer at a local Flea Market that had no other aviation stuff at all, let alone flight gear. Does anyone out there know the application of the MC-4 suit with a MB-5 helmet and about what year they would be used ? I also need to know if the early faceplate off my K-1 would be correct or do I need the later version, and what the proper bailout/suit pressurization bottle and reg assy is correct. I can't find any info one either of these items in any of the sources I have, I've seen references to the MC-4 suit, but nothing at all on the MB-5 version of the helmet. I'm assuming it may be a SAC issued version of the K-1 but I'm not sure ( I've read that "MB" designated gear was usually SAC issued, but I can't confirm that either) ANY help or info on this subject would be greatly appreciated.
Thank's John (Jetstuff)

Message 3571, Jul 24, 2001
Hi Wizzo, As far as I know the replica faceplates did not include details as fine as the actual demisting filigree, however, they certainly would fool anyone from a distance of more than 2 feet, from what I saw of them. I haven't seen "13 Days", although I'd like to, so I'll defer to someone who has seen it in the U-2 flightgear scene you mentioned.
Cheers, DocBoink

Message 3570, Jul 23, 2001
Last time I checked with Dennis, that faceplate he had posted didn't sell - I contacted him directly and he said the reserve had been $550. Lacking only the anti-fogging filament in the lens, I considered it worth every penny - just didn't have a spare K-1 for it to go on! If you really want it, he might still have it.
Maggot

Message 3566, Jul 23, 2001
Do the replicated faceplates have the electrical heating wire for the face shield? Another question: In the film, 13 Days, the U-2 suiting up in the MC-4 in chapter 26, would that be a real suit or a replica suit? To me, the lacing seemed a bit thicker than on the artifacts in my collection.
Wizzo

Message 3565, Jul 23, 2001
Downwind28, Another point to remember: Dennis Gilliam, the pressure-suit wizard, was able to fabricate faceplates for the K-1 and MA-2 helmets that were so authentic that they could nearly fool an expert. So, even if a faceplate doesn't materialise, there are ways to come up with these (rare) critical missing bits. Dennis auctioned off one of his fabricated faceplates on eBay a few months ago and I couldn't believe how accurately the fabricated faceplates appeared. I personally could not spot any differences between the real article and the replica. If he could do it once, he could certainly do it again (or show you how to do it yourself).
Good luck on the bidding. Cheers, DocBoink

Message 3564, Jul 23, 2001
Downwind28 - I wouldn't let the lack of a faceplate get in the way of bidding - the faceplates are rarer than hen's teeth to begin with - near as I can tell, everything else looks pretty decent on this item. If you can get it for $500 or less I would consider it a steal.
Maggot

Message 3083, Jun 22, 2001
I for one would love to see the photographs of that suit helmet (or the suit). I vaguely recall you mentioning this, but don't remember the image details. Sounds intriguing, however.
Cheers, DocBoink
----- Original Message -----
June 21, 2001
> A while back, A partial pressure suit helmet showed up on E-Bay. It had an oblong neck ring but was rather well made. I don't know if I still have pictures of this particular helmet, but I'll look.
> When I shopped this helmet around, the USAF pressure suit folks though
this helmet was designed by Dr. Lombard for Lockheed. I haven't received
official confirmation of this and I can't seem to find anything else on Dr.
Lombard.
> I do have a 1949 patent for a flight helmet. I'll have to check the name but it was Edwin ????. Diagram accompanying the patent loks very much like the H-1 with a bunch of snaps embedded on the sides(s) of the shell.
> Cheers, Steve

Message 2942, Jun 16, 2001
John, Thanks very much for sharing the most fascinating photographs of the MA-3. The MA-3 has always been for me one of the most interesting of the early (late 50s) pressure suit helmet developments. And who among us who grew up in that era could forget the indominatable "Colonel McCauley", who was regularly wearing his in that unforgettable, if a bit schmaltzy series. You are a luckily man indeed if your friend can find the matching suit for this rare item. It is well worth the wait, if you ask me, but I would be tempted to put a bit more pressure (no pun intended, but it certainly 'suits' the subject) on him to find it.
Cheers, DocBoink

Message 2901, Jun 13, 2001
Hi to group, The second set of Jpegs is of a Bill Jack MA-3 Pressure helmet. I got this right from the pilots son ( flew at Edwards in the late 1950's) The liner apparently turned to the same dust as the first helmet but the rest of it is in great shape. It's dated 2/58 and is serial # 68 The reference lines taped on the visor are kind of neat each one is identified by a tiny letter pencilled on. The owners son keeps promising me the matching suit if he can find it (swears it's in the attic, been waiting patiently for 3 years or so ....) I'll post some pic's of the early Toptex I have as soon as I get to photograph it.
John


MA-3 pressure helmet. © John 'Jetstuff' Spencer

Message 2880, Jun 12, 2001
Greetings to the Heresiarch of Uqbar, I am one who may know some answers to your questions. When "Men into Space" premiered, the spacesuit worn by Col McCauley was a USN Mark IV with MA-2/P harness. The subsequent episodes had the crews wearing helmets closer to the HGU-8/P, as shown in the attachment. So both Mk IV and HGU-8 types were seen. Our illustrious DocBoink can give you fine details about these helmets and suits used by Hollywood in their programs. Doc, could you provide the Heresiarch some info?
Gato

MA-3 pressure helmet © Gato

Message 2879, Jun 12, 2001
To anybody could know about: I'm in trouble trying to identify the MA-2 (made by ILC Dover) and HGU-8/P helmets, and the CSU-4/P partial pressure suit. If somebody has a good pic of any of them, I'll be glad. Am I wrong - or one of both hats was the costume issue often shown in some old scifi TV series like MEN INTO SPACE or THE OUTER LIMITS? Otherwise - how could be distinguished between pictures of an old Shuttle Launch/Entry Suit (LES) and the new Advanced Crew Escape Suit (ACES)?
Yours truly, The Rememberful Heresiarch of Uqbar

Message 2428, May 22, 2001
Downwind28, The USN Mk.IV was typically used in such 'spacious' aircraft as the F-4 Phantom II, the F8U Crusader, and similar types that had large enough crew spaces to allow use of the full pressure suit. It could be worn also in the A3J and RA-5 (Vigilante), but the A-4 Skyhawk ("Heinemann's hotrod") was just too cramped and confining to allow for comfortable use of such a bulky system.
I did not check the specific eBay item you referenced, but I do recall that a Mk.III was recently misidentified as a Mk.IV, so this may in fact be the one you refer to. Misidentification of Mk.III and Mk.IV helmets isn't that unusual among those who have less specific understanding of the differences between the two. You were therefore probably correct in your identification.
Cheers, DocBoink

Message 2419, May 21, 2001
Thanks for your quick response! What intrigues me is that the Mk IV is very close to the Mercury helmets - as close to an astronaut helmet one can possibly get without being a millionaire.
Downwind28

Message 2416, May 21, 2001
Hi Downwind28, Welcome to the group. The helmet you saw on ebay appeared to be an early Mark IV or a Mark III. The large neck ring and the shape of the visor, plus the old style regulator depict this. TAPKY (Ricardo ) on the group has a nice Mk IV helmet for sale.
Gato

Message 2412, May 21, 2001
To all: I am trying to educate myself a bit on MK-IV equipment. In a recent sale of a helmet described as a "MK-IV" on ebay (1141744831) I wrote to the seller that the piece looked more like a MK-III to me - but I never got a response. Was I right? In which aircraft was the MK-IV helmet typically used during the early sixties?
Regards, Downwind28