Space subsystems

This is the parent guide for space hardware: satellite buses, spacecraft propulsion, power and solar arrays, sensors and payloads, communications and ground segment, in-space servicing and launch. A buyer arriving from aviation should reset one expectation immediately. There is no equivalent here of a type certificate on a subsystem. The licensing that does exist sits on the operation: Part 450 sets the requirements for obtaining and holding a licence to launch, reenter, or both, with the vehicle operator licence defining its own scope, payload review and safety review.⁵ A reaction wheel, a solar array or a radio is not licensed by anybody. So the buyer's checks move to three other places.

First, the export list the item sits on

The United States Munitions List enumerates spacecraft, including satellites and space vehicles, by capability: among them those specially designed to detect a nuclear detonation, those that autonomously detect and track moving ground, airborne, missile or space objects in real time, those conducting signals or measurement intelligence, and anti-satellite systems.¹ Where an item is not described there, the list itself points onward to the Commerce Control List.¹ The Bureau of Industry and Security publishes the Export Administration Regulations, tools for classifying an item, country guidance and the Consolidated Screening List.² Ask a supplier for the classification of the exact item, who made that determination, and on what basis. A subsystem that is controlled under one regime is a different programme from the same subsystem under the other: different licences, different foreign national access rules, different schedule.

Second, the parts inside it

Space hardware is bought on its parts grade and its radiation evidence, not on its enclosure. NASA publishes its technical standards openly through the NASA Technical Standards System, which is where the workmanship and process documents a supplier claims to work to can be read.³ For electronics, the NASA Electronic Parts and Packaging Program publishes technical knowledge and recommendations on parts, and hosts the Goddard radiation test database and its publication lookup.⁴ That is a real check a buyer can run. Ask which parts grade the bill of materials is built to, ask for the radiation test reports on the specific part types and lots, and ask what the single-event and total-dose environments were assumed to be for your orbit and mission length. Ask what changes if a part goes end of life mid-programme, because it will.

Third, the qualification campaign

Ask whether the unit you are buying is qualification hardware, protoflight or a flight unit built to a qualified design. Ask for the test matrix: random vibration, shock, thermal vacuum cycling, thermal balance, electromagnetic compatibility, and the levels each was run at. Ask what heritage means in the supplier's sentence. Heritage that means the same design, the same manufacturing line and the same parts lots is worth a great deal; heritage that means a family resemblance is worth a conversation.

Questions that sort suppliers

Ask for the export classification and its basis. Ask for the parts list grade, the radiation data and the derating policy. Ask for the qualification test report, not the summary slide. Ask what the lead time is for the longest-lead item in the bill of materials, and when it was last quoted.

The companies below are listed on public facts, each with its source linked.