Technology Readiness Levels for Space Qualified Components

Launching a product into space is more complex than bringing an Earth-bound product to market. Components in space must be able to withstand the challenges of the space environment, function reliably for their expected lifetime without maintenance, and support the weight and size limits of the launch.

In this environment, product designers turn to Qualified Parts for Space (QPS) that have already been designed, tested, and vetted for successful use in space applications. QPSs have reached the highest Technology Readiness Level (TRL) as defined by the National Aeronautics and Space Administration (NASA).

TRLs ranging from 1 to 9 reflect a product’s journey from concept to successful performance (Figure 1). TRLs 1 through 3 focus on a basic idea being developed into a proof-of-concept that demonstrates how the item would theoretically operate. From TRL 4 to TRL 6, parts are put through initial testing and simulation. TRLs 7 and 8 bring the concept to fruition with the real-world test of a prototype and final demonstration of the technology.

Figure 1: NASA TRLs denote a space-bound product’s journey from initial concept to proven performance. Only a part with a TRL of 9 can be considered a QPS when it is manufactured and tested according to accepted standards. (Image source: Cinch Connectivity Solutions)

Products that reach a TRL of 9 have demonstrated successful performance in real-world space applications. In addition to reaching this high TRL level, parts need to pass specific test regimens to be considered QPSs. The standards controlling these requirements vary by part type. For instance, QPS attenuators must be tested to MIL-DTL-3933, level T, and QPS electronic connectors are governed by NASA’s EEE-INST-002.

Understanding the specific challenges of space-based applications can help designers choose existing QPSs that will perform to their requirements, shorten the path between concept and deployment, and bring the product to market on time and on budget.

Overcoming outgassing

The ability to operate in a vacuum and over temperature extremes is one of the largest hurdles that space-based components have to overcome. Vacuums in medium Earth orbit (MEO), 1,234 to 22,234 miles from Earth, where Global Positioning System (GPS) satellites operate, average 1 mTorr to 1 µTorr. At the same time, components in these and other applications are subjected to temperatures as low as -270°C in shadow and up to +121°C in direct sunlight.

When exposed to vacuum and heat, non-metal parts may experience outgassing, a phenomenon in which gases trapped inside the material during manufacturing migrate to the surface. This migration can result in fractures within the material, weakening it. Released gases may also condense and freeze on other parts of components, causing damage like blurred optics and fouled sensors.

The severity of outgassing is measured by the total mass lost (TML) from a component when it is subjected to vacuum and heat, as expressed as a percentage of the original mass. Manufacturers also measure the percentage of collectable volatile condensable materials (CVCM), the amount of outgassed matter that condenses on a colder surface. Both tests are performed under the ASTM E595 protocol in which the sample is held at +125°C and at less than 5 x 10^-5 Torr for 24 hrs.

Most electronic components must pass outgassing tests to be designated QPS because they use non-metal insulation and shielding materials. This is the case for Cinch Dura-Con™ space-screened micro-D plugs and sockets (Figure 2) from Cinch Connectivity Solutions. The non-metals in Dura-Con connectors, the thermoset insulator around the pins and the ethylene tetrafluoroethylene (ETFE) wire insulation lose less than 1% of their total mass in testing and have less than 0.01% CVCM.

Figure 2: Dura-Con connectors use low-outgassing insulating materials to exceed NASA’s EEE-INST-002 standard for electronic connector selection for LEO applications. (Image source: Cinch Connectivity Solutions)

These nickel-plated connectors conform to the MIL-DTL-83513 for microminiature rectangular electrical connectors. They accommodate nine to 100 pin positions in footprints from 0.775" to 2.160" wide, by 0.298" to 0.384" tall.

Their design and low level of outgassing position them for applications in low Earth orbit (LEO) at up to 1,200 miles of altitude per NASA’s EEE-INST-002 standard for electronic connector selection. The Hubble Space Telescope, the International Space Station, and the constellations of microsatellites that make global telecommunication possible orbit in this zone.

The EEE-INST-002 standard also recognizes three levels of criticality for electronic connectors. Level 1 connectors are mission-critical, level 2 connectors require high reliability, and level 3 connectors are rated for standard reliability. Dura-Con connectors are screened to level 2.

Reducing radiation interference

In addition to the hazards of vacuum and temperature extremes, components in space also have to contend with increased levels of radiation. Without the protection of Earth’s atmosphere, these components encounter the full spectrum of ultraviolet (UV) radiation. Outside of LEO, gamma rays and other ionizing radiation are also of concern. Radiation can shorten the life of non-metal components, and it can degrade electromagnetic signals with radio frequency interference (RFI) and electromagnetic interference (EMI) in general.

Electrical connectors that combat this, like the Trompeter QPS electrical connectors from Cinch Connectivity Solutions, have robust RFI and EMI shielding, enabling them to meet the MIL-STD-1553B data bus specification.

They are also constructed mainly of metal, including gold-plated beryllium copper contacts and a nickel body. A low-outgassing polytetrafluoroethylene (PTFE) dielectric material achieves TMLs less than 1.0% and CVCMs less than 0.10%.

The space rated Trompeter series includes miniature connectors in two connection styles. TRB connectors are a bayonet-style lock (Figure 3), while TRT connectors attach with a screw thread (Figure 4). Each type comes in several designs to allow it to connect through bulk heads, at the end of cables, or via printed circuit boards (PCBs).

Figure 3: TRB space rated miniature bayonet connectors have excellent RFI and EMI shielding and low outgassing. (Image source: Cinch Connectivity Solutions)

Figure 4: TRT space rated miniature threaded connectors can attach through bulkheads, to cables, or by attachment to PCBs. (Image source: Cinch Connectivity Solutions)

TRS subminiature bayonet connectors (Figure 5) and TTS subminiature threaded connectors (Figure 6) share the robust signal transmission of their larger counterparts. Their smaller size allows for more efficient use of the limited space available on satellites and other orbital vehicles.

Subminiature parts also address another design difficulty of space applications: the cost of launching them into orbit. In 2025, the cost of launching a kilogram of mass into LEO was $3,000. While that is more than an order of magnitude less expensive than the $50,000/kg during the Space Shuttle era, it still puts weight at a premium. Subminiature QPS connectors can help reduce weight and save money.

Figure 5: TRS space rated subminiature bayonet connectors reduce launch weight and cost while maintaining excellent signal transmission performance. (Image source: Cinch Connectivity Solutions)

Figure 6: TTS space rated subminiature threaded connectors use low-outgassing insulating materials to exceed NASA’s EEE-INST-002 standard for electronic connector selection for LEO applications. (Image source: Cinch Connectivity Solutions)

The low outgassing, lightweight, and high-quality signal transmission of Trompeter connectors has led to their use in communications satellites in LEO, GPS satellites in MEO, and on Mars in NASA’s rovers.

Components built to launch and last

Cost considerations are not the only design challenges related to launching components into space. Parts must be able to endure the acceleration and vibration of launch as well as thermal shock, performing as well after these shocks as they did on a test stand.

The MIL-DTL-3933 standard sets out qualification and screening requirements for radio and microwave fixed attenuators, which reduce signals’ power without distorting their waveforms. The standard provides specific guidance, labeled level T.

QPS attenuators (Figure 7) are tested to and meet the MIL-DTL-3933 level T requirements, offering attenuation values from 0 dB to 20 dB with accuracies ranging from ±0.3 dB to ±0.7 dB. Constructed of stainless steel and beryllium copper with a PTFE dielectric and a fluoroelastomer gasket, they meet or exceed outgassing requirements.

Figure 7: QPS attenuators reduce the power of radio or microwave signals from 0 dB to 20 dB. They have been used on GPS satellites and interplanetary missions. (Image source: Cinch Connectivity Solutions)

These attenuators are available in three screening levels that reflect the attenuator’s end-use application. Level A checks all parts for attenuation performance before and after application of peak power and is for non-flight applications. Level B, the minimum pre-space-flight screening, adds launch stressors like thermal shock and vacuum conditioning to the evaluation and is used for parts on satellites entering LEO. Level C adds thermal cycling and vibration to the screening process and is recommended for any space-bound parts, including those headed to geostationary orbits (22,234 miles from Earth) and beyond.

Conclusion

QPS components that have achieved a TRL of 9 by performing successfully on previous space flight missions have proven to have a long, maintenance-free lifespan and can withstand extreme temperatures, shock, vibration, vacuum, and radiation. Manufacturers of QPSs have developed screening protocols that ensure that 100% of their space rated, space-bound parts are up to the challenges presented by operating in orbit or in deep space today and into the future.