The various configurations of the connectors are intended for use as follows:

a. Series I connectors: General application within weapon system where a quick disconnect coupling system is required for blind mating or other mating problem areas. These connectors provide high-vibration characteristics and are suitable for severe wind and moisture problem (SWAMP) areas with proper connector accessories.

Class G, finish F: Provides a conductive shell for EMI considerations but with additional requirements for space grade applications.

Class H: Same as class Y, but with additional requirements for space grade applications.

Class T, finish F: Provides a conductive shell for EMI considerations.

Class Y: Applications where pressure must be maintained.

Classes R and U: Applications requiring high corrosion resistance.

b. Series II connectors: General application within weapon systems which are not subjected to high vibration or SWAMP areas. These connectors are not scoop-proof (see 6.1.1). Connectors are lightweight.

c. Series III connectors: General application within weapons systems and are suitable for blind mating areas. These connectors provide high-vibration characteristics at elevated temperature and are suitable for SWAMP areas with the proper connector accessories.

Class W: Provides a corrosion resistant, conductive shell.

Class F: Provides a conductive shell for EMI requirements.

Class K: Provides a stainless steel, firewall connector for engine applications.

Class L: Provides a stainless steel connector with conductive plating for enhanced EMI performance for general applications.

Class S: Provides a stainless steel, firewall connector with conductive plating for enhanced EMI performance.

Class Y: Applications where pressure must be maintained.

Class J: Provides a corrosion resistant, lightweight composite shell with conductivity equivalent to class W.

Class M: Provides a corrosion resistant, lightweight composite connector with conductive plating for EMI performance equivalent to class F.

Class N: Provides a hermetically sealed connector with conductive plating for enhanced EMI performance.

Class G: Same as class F but additional requirements for space grade applications.

Class H: Same as class Y but additional requirements for space grade applications.

Class R: Applications requiring high corrosion resistance (for metallic shells).

Classes

T, V, Z, AA, AB: Applications requiring alternatives to cadmium plating.

d. Series IV connectors: General application within weapons systems where a quick disconnect coupling system is required for blind mating or other mating problem areas. These connectors provide high-vibration characteristics and are suitable for SWAMP areas with the proper connector accessories.

Classes W, F, G, H, J, M, and Y: Same as series III.

Class R: Applications requiring high corrosion resistance.

Classes T, V, Z, AA, AB: Applications requiring alternatives to cadmium plating.

Class N: Provides a hermetically sealed connector with conductive plating for enhanced EMI performance.

e. Series I and II are intermateable with MIL-DTL-27599, series I and II, respectively

Application guidance and restrictions.

a. When evaluating connectors for use in new design systems and support equipment, users are advised to evaluate carefully for each application the relative merits of the long shell series I, III, IV, and short shell series II connectors. When considering use of the short shell series II connectors, the following areas must be evaluated:

(1) Series II connectors are vulnerable to pin contact bending from scooping, with contact size 22 being the most vulnerable.

(2) Use of series II connectors must be avoided in areas of blind mating.

(3) Receptacles must be located so as to minimize the amount of required cable bending. When using series II connectors with large cables which must be bent at right angles, the cables must have the right angle bend permanently established.

(4) Series II connector should not be used with heavy jacketed cable and excessive overhang moments, because of possible shell damage.

(5) Series II connectors should not be used in areas of rough handling such as experienced near engine removal, generators, support equipment, or portable equipment, etc.

(6) When mating series II connectors in areas of difficult visibility, care must be exercised to make sure that all bayonet pins are engaged by the coupling ring, since it is possible to engage only one bayonet pin and therefore only partially couple.

(7) When mating series II connectors in areas of difficult visibility, care must be exercised to make sure that connector plugs with pins are not coupled to receptacles with pins. This situation will result in the contacts touching.

b. When the use of series IV connectors is considered, the design of the coupling system should be evaluated. If the coupling mechanism between the coupling ring and the shell is not properly positioned prior to the mating operation, the coupling ring must be repositioned prior to mating.

c. Series I and II, class P connectors should not be used in Air Force new design applications, except when specifically approved by the procuring activity.

d. Application restrictions concerning the use of these connectors are set forth in MIL-STD-1353.

Additional application restrictions are listed below:

(1) Finish A, series I and II, is inactive for new design.

(2) Class E, series I and II wall mount and jam nut receptacles: Inactive for new design. For new design requiring wall mount or jam nut types, use class T.

(3) Class P, series I and II, (for potting): Inactive for new design for Air Force.

(4) Finish F, all environment resistant classes, series I and II: Finish F is not for Navy use. Finish F is inactive for new design for Air Force use.

(5) Class F, series III and IV: Class F is not for Navy use. Class F is inactive for new design for Air Force use. Since class G has the same finish as class F, Class G is not for Navy or Air Force use (see note below).

Note: Classes or surface treatments and finishes that are listed as "inactive for new design" are not for use in new design or equipment, but may continue to be used to support existing designs or equipment. Classes F and G are considered to be unsuitable for Navy and most Air Force applications due to the relatively low corrosion resistance of the electroless nickel surface finish.

e. Recommended panel cutout dimensions are shown on figure 11.

f. Compatibility of connectors should be addressed when intermating different classes and finishes. Galvanically incompatible classes and finishes should not be intermated together. When intermating classes with different performance requirements, the lower performance requirements of the two classes apply.

g. Composite class connectors should be considered for applications requiring increased corrosion resistance, increased durability, or decreased weight.

h. Box mount connectors are intended to be used on environmentally sealed boxes. If full wire sealing capability is needed, a wall mount or jam-nut mount connector should be used.

i. A summary of shell materials and finishes for each series is listed in table XX.

j. For environment resisting classes, wire sealing for size 8 shielded (twinax or coax) contacts for some insert arrangement, including 17-2, 19-18, 21-75, 25-7, 25-8, 25-20, 25-46 and 25-90, may be accomplished by the use of separate non-standardized sealing boots that are furnished with the connector (see 3.4.3.2.2) (note: some manufacturers' designs may accomplish wire sealing with a heat shrink sleeve, only; the majority of qualified connectors with insert arrangement 25-20 use a heat shrink sleeve with size 8 contacts ). If size 8 shielded contacts with sealing boots for the above-listed insert arrangements are replaced, it is recommended that the boots be retained for use with the new contacts. Insert arrangements 17-3, 19-19, 21-76, 25-9, 25-10, 25-21, 25-47 and 25-91, which use size 8 shielded contacts, require the use of a standardized sealing boot in accordance with MIL-DTL-38999/62.

k. Class T, series III and IV and finish T, series I and II, is required to be nonreflective. Finish W is required to be an olive drab color in accordance with SAE-AMS-QQ-P-416. Class Z is required to be black in accordance with ASTM B841 (see 3.3.6.4). These nonreflective finishes and colors may vary in color depending on the method of manufacture. This variance in color does not alter the performance capabilities of the finish.

l. Storage, cadmium plated connectors: See SAE-AMS-QQ-P-416 for packaging limitations for cadmium plated products. Users are advised that cadmium plated parts should not be packed in non-ventilated containers or in direct contact with wood or cardboard, especially under conditions of high humidity or moisture, due to a corrosive reaction that often occurs between the cadmium plating and organic acids (i.e. formic acid, butyric acid, etc.) which form under these conditions.

m. Composite connector plating: The plating on composite class J and M connectors is subject to minor chipping (i.e., chipped places in plating less than 1.02 mm (.040 in)). This minor chipping is considered a cosmetic issue. As long as the composite base material is intact in the exposed area of the chipped plating, the chip should not affect form, fit or function. Connector shell areas most often subject to minor chipping include the keys or keyways, the mounting flange edges, or the plug shell nose.

Note: The term stainless steel (SST in table XX) is used interchangeably with the term "corrosion resistant steel" in this specification.

Derating factors (see 6.4).

a. Environmental: Throughout this specification, test requirements attempt to simulate actual environmental conditions for applications in which the connectors are expected to be utilized. The application designer is encouraged to carefully compare the electrical, mechanical and environmental test requirements of this specification with the parameters of their application when considering their use in the application. As an example, for applications in which altitude is an environmental factor, in this specification, dielectric withstanding voltage strength decreases as the altitude is increased and air pressure decreases (see table III). MIL-STD-1353 and SAE-ARP1308 provide additional information on the selection and use of military standard and associated SAE standard electrical connectors.

b. Lowest performing members: Users and suppliers of connectors should be cognizant that the lowest performing member of a connector assembly may necessitate derating the performance characteristics of the connector. Lowest performing members may include standardized crimp contacts (both power contacts and multi-axial), shrink boots (also called shrink sleeves), and sealing boots (see MIL-DTL-38999/62). See 6.1.2.c for additional information on crimp contact issues, including standard socket contacts for series I, III and IV, SAE-AS39029/56.

c. Vibration at temperature and SAE-AS39029 contacts (see table XXI) versus MIL-DTL-38999:

Power contacts - For qualification, vibration requirements for AS39029/56 contacts are equivalent only to MIL-DTL-38999 series III, random vibration at ambient temperature. Contact qualification testing for listing product in accordance with AS39029/56 on QPL-39029 does not include all vibration requirements specified by MIL-DTL-38999 series III (see 4.5.23). AS39029/56 does not require random vibration at elevated temperatures or sine vibration. Connectors with insert arrangements specifying AS39029/56, the standard power socket contact, are not recommended for use in applications in which high temperature and high vibration are critical environmental factors. Where high vibration and temperature are concerns, recommend AS39029/121, an "expanded performance" socket contact that includes vibration at temperature testing equivalent to MIL-DTL-38999. (Note: Some qualified connector manufacturers are also qualified for AS39029/56. Qualified connector manufacturers that use their own qualified AS39029/56 contacts for MIL-DTL-38999 qualification and periodic requalification are required to conduct MIL-DTL-38999 vibration at high temperature. Therefore, their qualified AS39029/56 contacts are expected to meet all the requirements of MIL-DTL-38999).

Multi-axial contacts - Multi-axial SAE-AS39029 contacts designed for use with MIL-DTL-38999 connectors, including shielded, coax and twinax contacts, do not undergo qualification vibration testing at the maximum operating temperatures required for series III connectors. No standardized high vibration/high temperature multi-axial contact that meets MIL-DTL-38999 series III vibration at temperature requirement is currently available. Connectors with insert arrangements that include multi-axial contacts are not recommended for use in applications in which high temperature and high vibration are critical environmental factors.

d. The use of non-standardized accessories that potentially compromise or otherwise alter the environmental sealing between the mating connectors, including products that are intended for EMI sealing, are not for Navy or Air Force use. Army users should carefully review their requirements if they intend to use non-standardized accessories. Usage of EMI sealing devices is permitted in testing / laboratory situations that are unrelated to qualification and requalification testing.

Military unique statement.

This connector is military unique because it is a miniature, high density, bayonet, threaded, breach coupling, environment resisting, high shock, high vibration, high corrosion connector that uses crimp removable or fixed hermetic solder contacts. It is capable of operating at temperatures up to 200°C. It is also designed to withstand salt spray for a duration specified in table II. This connector is the most versatile and most preferred for military applications.