The NASA EEE-INST-002 provides instructions for choosing space connectors based on mission needs and requirements. Space connectors are utilized within the electronic equipment used in space applications, whether on a spacecraft or a satellite. To qualify for certain specific missions, the connectors must be tested and approved by NASA under EEE-INST-002 standards. Like all other components used in space, the connectors must also meet the stringent testing for outgassing (the release of trapped air) and residual magnetism to be suitable for use in space applications. These recommendations are laid out under NASA’s EEE-INST-002 guidelines for reliability.

NASA’s EEE-INST-002 has laid out three reliability levels of equipment that can be used for several space explorations. The term  “Level” is attached to each component. 

• Level 1 part has the highest performance & reliability while the Level 3 part has the lowest. The Level 1 part has the highest manufacturing control and testing as per military or DSCC (Defense Supply Center Columbus) specifications and low-risk parts for missions 5 years or longer. 
• Level 2 part has reduced manufacturing control and has been tested for space mission duration between 1-5 years. 
• Level 3 part has no guaranteed reliability controls in the manufacturing process and no standardized testing requirements for programs with a mission duration of less than 1 year and up to 2 years. The reliability of this part can vary significantly with each manufacturer, part type, and LDC due to unreported and frequent changes in design, construction, and materials and are more likely to fail than level 1 part.

Connectors used in Level 1 and Level 2 space flight applications are highly-reliable. Examples of Level 1 or 2 may include connectors with a hood “clamping” mechanism surrounding the female contact engagement that is typically used with circular military socket contacts or the reverse gender “bulged wire twist” pin used with microminiature (Micro-D) style connectors.

Connectors used in Level 3 applications should also employ similar contact systems as those approved for Levels 1 and 2. 

The following connectors are prohibited for Level 1 and Level 2 applications and are not recommended for Level 3 applications as well under the EEE-INST-002 standards. 

• Compact PCI connectors and 2 mm Hard Metric connectors, as well as other connector designs (e.g. Eurocard, VME) with flat bifurcated “tuning fork” type female contacts.
• Other connector contact systems have two points of contact engagement, or less, that do not utilize a military-style hood “clamping” mechanism to support female contact engagement tines. 
• Connectors with compliant pin “press fit” terminations to flight boards.
• MIL-DTL-55302/ 131 through 134 Eurocard type PWB connectors.
• MIL-DTL-55302/ 157 & 158 VME type PWB connectors.
• All MIL-C-28754 & MIL-A-28859 modular connectors and assemblies.
• All MIL-DTL-32234 blade and fork connectors.
• All DSCC drawing high-density blade and fork connectors.

Click here to learn more about NASA EEE-INST-001 Standard.