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A/P22S-3 full pressure helmet

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Just recently I was able to acquire a fine specimen of the A/P22S-3 full pressure helmet. This made me dig in to manuals and other resources to find more information on this helmet and set up. Sources are not all very clear on the (operational) use of this set. I hope the below text sheds some light on the use of this suit.


In 1959, the USAF adopted the US Navy Mk IV lightweight full pressure suit, designating it the A/P22S-3 full pressure suit. The Air Force was looking for a pressure suit that could be used by the ADC. Pilots where trained to fly a parabolic pattern to a very high altitude to intercept high flying enemy bombers or spy planes. At the top of this run, the air to air weapon would be released (sometimes even a nuclear example) and the ADC aircraft would lose engine power (engine stall) and sore down to earth, a restart was made at a lower altitude to head back home. During the training of this manoeuvre no aircraft were lost.


In 1962 the Air Force standardized to the A/P-22S-2, after some intensive testing (among others Project Cold Case). The -2 suit is essentially the same design, but is constructed of four layers instead of the two in the -3 version. In FY62, the USAF completed its evaluation of several new developmental items of pressure suit equipment. These items included the CSU-4/P partial pressure suit, as well as the A/P22S-2 and -3 full pressure suits. The utility of these suits of facilitating survival either at altitude or on land or water was the primary consideration. Meanwhile the CSU-4/P was designated alternate standard for use on the F-104 Starfighter. (The German Luftwaffe adopted the same suit named S-922 suit in orange or green.)


Until 1969 the suit appeared in manuals and reports, but must have been replaced by the -2 version years before. Known helmets were dated 1960 and 1961.


The operational use might have been wider spread then thought. Reports indicate use at 332 FIS at Thule Greenland (flying the F-102). The crew of this unit was sceptical of the survivability in cold water and after a long discussion, the BF Goodrich representative and an Air Force specialist, jumped in the ice cold water dressed in complete suits. One of them even climbed a small ice berg and both stayed in the water until the watching pilots left because they were getting cold.

Another unit at Harmon AB (also flying the F-102) had several complaints about the suit, resulting in a pilot refusing to wear it any longer. The main reason was the fitting of the suit, that left a lot to be desired. If this was caused by improper fitting by the PE specialist, or just the lack of suitable sizes, is not known.


Below an excerpt out of an USAF manual on the A/P22S-3. If anyone has more information on the operational use, please let me know.




Construction of the A/P 22S-3 Full Pressure Suit:


a. Purposes.

The purpose the A/P 22S-3 Full Pressure Suit is to protect the flyer from hypoxia under conditions that might be encountered in normal high altitude flight. The -3 suit also gives the flyer protection if there is an emergency situation; for example, an ejection or loss of cabin pressure. Breathing oxygen is provided by the suit assembly during normal flight with the cabin altitude at and below 35,000 feet. If cabin pressure is lost above 35,000 feet, breathing pressure is provided and also an internal suit pressure of 3.4 psi (barometric and suit pressure) absolute is maintained. If of ejection or loss of the aircraft's oxygen supply, the suit utilizes the emergency oxygen supply to provide the breathing pressure and the internal suit pressure.

b. Component Parts.

Torso, gloves, standard flying boots, and a helmet are the major components of the A/P 22S—3 Full Pressure Suit Assembly.


c. The Torso.

The torso is constructed of two layers:

(1) The outer layer is constructed of nylon to prevent excessive ballooning. The outer layer is called the restraint layer. The three major areas for the fitting adjustments are located on the restraint layer. These fit ting adjustments are the length adjusting straps, the lacings, and the restraint straps. Pockets are located on the restraint layer for pencils, a survival knife, and arctic exposure mittens. Access zippers are located in the neck area and the sock endings for ease of donning the suit. A gusset zipper is located completely around the mid-section of the restraint layer to allow donning of the neck ring. The entrance zipper is located diagonally on the front of the restraint layer. This zipper is a pressure sealing zipper.

(a) Other items located on the restraint layer are the controller, the altimeter, and the pressure relief valve. The controller initiates the pressurization of the suit assembly. The altimeter reads total pressure of the suit assembly in thousands of feet when the suit assembly is used at altitude. The pressure relief valve is set at a pressure range of 3.5 psi to 4.0 psi to prevent over-pressurization of the suit assembly.

(b ) The suit contains a ventilation system that starts with a hose located on the restraint layer. It leads to the inner layer of the suit. The ventilation system on the inner layer of the suit is made up of ducts leading to six areas. These areas are the two feet, the two hands, the buttocks, and the neck. From these extreme outer locations the ventilation air flows over the body and then through the controller to the outside of the suit.

(2) The inner layer of the suit torso is a bladder constructed of two different materials. The material for immobile areas of the suit is constructed of nylon impregnated with chloroprene. The purpose of the nylon is to restrict excessive ballooning of the suit. The purpose of the chloroprene is to retain the gas that pressurizes the suit. The material for the mobile areas of the suit is constructed of Helenca coated with neoprene. The purpose of the Helenca is for mobility in the suit. The purpose of the neoprene is to retain the gas that pressurizes the suit.


(a) The gloves are constructed of two layers. The outer layer is nylon with a leather palm. The inner layer is Helenca coated with neoprene. A restraint wire is located in the palm of the gloves to serve as a breaking point. There are also two restraint straps located on each glove. The gloves are attached to each arm of the torso by zippers. There are O-rings on each glove for sealing the gas inside the suit assembly.

(b ) Boots are part of the suit assembly to protect the feet and also to support the sock endings when the suit assembly is pressurized.


d. The Helmet.

The helmet is manufactured in two sizes. Each helmet has a different size neck ring and must be attached to a suit with the corresponding neck ring size. The helmet is attached to the torso by means of a disconnecting ring. There is an O-ring on the helmet that seals the gas pressure in the suit assembly. The helmet consists of the following parts:

(1) A regulator.

(2) A clear face piece.

(3) A face piece seal tube.

(4) A defogging tube.

(5) A face Seal.

(6) A wind-up knob assembly.

(7) A shaded visor.


(a) The regulator is located on the left rear of the helmet. An off and on switch is located on the regulator for its operation. A 70 psi oxygen line comes from the control ler to the regulator. The regulator has three functions. One function is to supply 70 psi of oxygen to the face piece seal tube to seal the clear face piece. There is a latch on the left side of the helmet that operates the clear face piece. A second function is to supply oxygen through the defogging tube to spray across the clear face piece to prevent fogging of the face piece. A third function of the regulator is to supply breathing oxygen through the defogging tube at about 1 to 1.5 inches H.O pressure above suit pressure and at 95 Liters per minute (lpm) flow.

(b ) There is an anti-suffocation feature located in the off and on switch of the regulator. If the flyer's oxygen supply is depleted, the clear face piece will remain sealed for 30 to 45 seconds to give the flyer a warning that his oxygen supply is gone. Then it will release in this 30 to 45 second period to prevent the flyer from suffocating in case of an ejection where the flyer has remained in the complete suit assembly and has become unconscious.

(c ) The helmet is divided in two pressurized sections by means of the sponge rubber face seal. The forward section is the breathing section and the rear section is part of the suit pressurized section. A wind up knob is located at the right rear of the helmet. This knob is part of an assembly. This assembly has straps attached to the face seal to give the flyer a good seal when the knob is rotated.

(d) The latch on the right side operates the shaded visor. The shade visor has two positions – completely up and completely down. The purpose of the visor is to prevent sun glare.


Sizing and Fitting of the A/P22S-3 Full Pressure Suit:


a. General Procedures.

There are four major procedures for fitting the A/P 22.S.–3 Full Pressure Suit. The selection of the torso, gloves, boots, and helmet is first. The donning procedure is second. After the suit is donned the fitting adjustments are taken up. Following the final fit of the suit, the suit assembly is pressurized to check for a good fit and for proper operation.

b. The Torso.

The suit torso is manufactured in 12 sizes. Expanded chest circumference and vertical trunk circumference are the two measurements to be taken for the proper selection of the suit. Expanded chest circumference indicates how large the suit shall be. Vertical truck circumference indicates whether the suit will be short or long.

c. The Gloves.

There are 7 sizes of gloves. The measurements that determine the glove selection are palm circumference and middle finger length.

d. Boots.

The boot should fit the person snugly. But they should not be tight enough to restrict blood circulation. The boot size should be at least 1/3 size longer than the street shoe size and the same width or wider.

e. Helmet.

The helmet comes in two sizes. The Smaller helmet should be tried on first. If the small helmet does not fit and the larger helmet is selected—then the suit with a large neck ring must be selected.

f. Donning.

Now that all of the components of the suit assembly are selected—the suit is ready to be donned. The suit should be completely unlaced. All of the length adjusting straps and restraint straps should be loosened. Then the suit is donned with sock endings first. The next step is to don the boots. The suit is carefully pulled up over the buttocks. The arms are inserted. When the person is pulling up the buttocks of the suit and inserting the arms, care should be taken not to damage the entrance zipper. Next the gusset zipper is completely opened. The neck ring can now be donned. After the neck ring is donned the gusset zipper is closed. The gloves are donned, and ventilation air is supplied to the suit.

g. Straps and Lacing Adjustments:

(1) At this point the straps and lacings are adjusted. The straps and lacings are adjusted in the following sequence, the length adjusting straps, the lacings, and the new restraint straps. The lacings and straps should be adjusted snugly, but not tightly enough to cause any restriction. Now the helmet is donned, and the complete assembly is ready to be checked.

(2) The final check out of the suit assembly is performed to check the fit and the operation of the assembly. This is done by pushing the press-to-test button on the controller. This supplies 2 to 2.5 psi pressure in the suit. At this point the fit and the operation of the –3 suit assembly can be checked.





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Extraordinary helmet and great information.


Thank you!


Some more images of this helmet:




(Boom microphone put back in place by now)




The helmet came with the same case bottom as used for the Mk.IV helmet cases.

Images show the original cases have the USAF logo where the Mk.IV has the navy wings, see image in the next post.




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See this image (source unknown) of a very nice series of HA gear.

Next to the MK.IV set is an A/P-22S-3 set and further down the line the A/P-22S-2 and an HGU-51/P ICDS set.


attachicon.gifHA sets.jpg




such a sight almost makes me feel sick... gulp!! What an incredible of a (private, maybe?) gem of museum... I would be super-happy if someday will be able to complete a mannequinn like the first from left-side - currently I've got the MC-1 suit and back parachute, so where is the problem? I need ONLY the partial-pressure helmet, its faceplate, the proper connectors/oxy. reducers, the pressure gloves, and the proper oxy. emergency bottle.


Maybe later, in some next life ah ah... Thanx very much!! Great topic and great pictures .


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...just noticed lately an interesting detail,

the said mannequinn at left side is wearing a typical Navy MA-2 harness of the very early pattern (full-torso w/ 'rocket-jet' fittings) thus the setup could represent a Navy test pilot being equipped with a C-1 partial pressure suit, sort of a USAF T-1 model having some modifications. If so, an even rarer subvariation.

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...just noticed lately an interesting detail,

the said mannequinn at left side is wearing a typical Navy MA-2 harness of the very early pattern (full-torso w/ 'rocket-jet' fittings) thus the setup could represent a Navy test pilot being equipped with a C-1 partial pressure suit, sort of a USAF T-1 model having some modifications. If so, an even rarer subvariation.


Could indeed be a C-1a suit, but the parts of the suit that could clearify that, are obscured...

Good observation on the harness!

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could be (but not sure, some details aren't visible) the proper multi-outlet connector for the MC-1 partial pressure suit, or at least it is similar. However if putting a strictly Navy item like the MA-2 torso harness on that mannequinn has been not an error (rather unlikely it was, given the quality and competence required for such a display of characters) that high-altitude flyer should wear the C-1, the only Navy partial pressure suit being specifically contracted by the service - as long as I'm aware.

Thus by logics it couldn't be a USAF/NACA MC-1 suit, and the terminal block is not MC-1's required (and a decidedly particular one) type.


More I cannot say - would be quite interesting to have a closer and best defined view.

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Some more on the topic of the A/P22S-3 suit, during march 1964, the USAF School of Aerospace Medicine, Aerospace Medical Division (AFSC) at Brooks AFB, studied an "Urine evacuating system for use in full-pressure suits"

This was done to prepare for manned space flight, several tests were conducted and all succesfull.

See this schematic for the systems way of working.






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Another study (Final Report Project ADC/73AD/62- 29 A/P22S-3 Suit Controller) dated january 1963, was done on the combination A/P22S-3 suit and B-5 parachute.

During another project, a fitting broke from the suit controller on a larger size suit by a parachute harness. The break stopped the flow of oxygen for breating and suit inflation.


A fix for this issue was proposed and consisted of adjusting the B-5 harness to a higher than average index number (making it wider/larger) when wearing an A/P22S-3 suit.

Furthermore, the suit controller was rotated clockwise by 60 degrees. (One mounting screw hole)


Testing was done by use in the pressure chamber, suspension and jump test, a simulator flight and two flights in a F-106B. All completed satisfactory.


Hard to see in this image, but it shows the controller on the front of the suit and the B-5 harness.






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