Which satellite components can use COTS parts?

First, distinguish a catalog subsystem from a consumer part

ESA describes a CubeSat ecosystem of commercially available subsystems with predefined interfaces. Buying an off-the-shelf satellite subsystem is not the same decision as installing an unmodified consumer electronics board.

A useful RFQ makes that distinction explicit: are you buying a discrete component, a board for adaptation, or an integrated subsystem? Ask what design, integration, and verification work remains with your team. A common form factor can simplify assembly without settling every electrical, software, or environmental question.

Sources: ESA — Technology CubeSats

Computing: consider recoverability, not just performance

NASA’s 2026 avionics overview describes combinations of commercial, radiation-tolerant, and radiation-hardened technologies. It also discusses mitigation approaches such as watchdogs, selective power cycling, and fault isolation. The architecture around a processor matters alongside the processor itself.

Our design-review suggestion is to separate high-performance processing from the functions that must remain available for recovery. Ask whether the system can detect a failure, restore service, and preserve a dependable command path. Redundant boards are not automatically independent if a shared dependency can disable both.

Sources: NASA — 2026 Small Spacecraft Technology: Avionics

Power: commercial options exist, but protection is not optional thinking

NASA’s power survey documents the use of both COTS and space-oriented technologies. It also notes differences in the protection and telemetry features available across power-management products. A catalog label alone does not establish whether an electrical power system fits a mission.

When comparing options, our recommended worksheet includes the required loads, operating modes, protection behavior, recovery assumptions, and evidence behind the offered configuration. Keep the purchasing decision separate from the engineering acceptance of a battery assembly or a power-distribution design.

Sources: NASA — 2026 Small Spacecraft Technology: Power

Mechanical and material choices deserve their own review

A bracket or harness may look simpler than a computer, but the material and assembly still matter. ESA’s materials laboratory highlights outgassing contamination and stresses associated with thermal cycling among the concerns it evaluates.

Do not turn “passive” into shorthand for “no review needed.” Ask what materials and processes are used, how the hardware is retained and connected, and what evidence applies to that exact assembly. In particular, consider nearby sensitive surfaces when reviewing adhesives, coatings, and other material choices.

Sources: ESA — Materials and Components Laboratory Testing

Use a failure-consequence map to prioritize the review

The following is a Fairwinds editorial triage tool, not a qualification matrix or permission to fly a particular product. The examples describe questions to ask; they do not assign a universal safety rating.

Build a shortlist that engineering can actually approve

For each candidate, record three decisions: why it is on the shortlist, which evidence is still missing, and who can accept the residual risk. If a substitution changes any of those answers, reopen the review rather than treating the new part as a procurement-only swap.

Our recommended order is simple: establish the function, compare the evidence, then compare the commercial offer. A low quote is useful only when the team understands the work and uncertainty that come with it.