Sourcing Spacecraft and Satellite Hardware

Spacecraft parts in one paragraph

Spacecraft and satellite hardware is mostly low quantity, high value machining and electronics work where the part has to survive launch loads, then thermal cycling and vacuum for years with no chance of repair. That pushes three requirements onto suppliers that ordinary aerospace work rarely sees together: materials restricted to an approved list or covered by a usage agreement, contamination control including outgassing limits, and records complete enough to support a failure investigation long after delivery.

Typical hardware bought from suppliers

For alloy and temper details see aluminum alloys, titanium alloys and controlled expansion alloys.

Materials and processes: NASA-STD-6016 and the usage agreement

On NASA spacecraft work the baseline materials and processes requirement is NASA-STD-6016, Standard Materials and Processes Requirements for Spacecraft. Revision C was approved in September 2021, and NASA's standards site lists C with Change 1, approved November 2023, as the active version. Its scope covers materials and processes used to design, fabricate and test flight components on crewed, uncrewed, launch vehicle, lander and in-space systems. Many commercial and Space Force programs write their own M&P documents along the same lines.

The key mechanism is the material usage agreement. When a material or process is technically acceptable but does not meet the standard, the program documents the rationale in an MUA. Revision C also requires MUAs for hazardous fluid compatibility verification, points additive manufactured hardware to NASA-STD-6030, adds a composite NDE requirement and calls out CMH-17 Volume 6 for structural sandwich.

For a supplier this means:

• Do not substitute a material, form, temper, finish, adhesive, lubricant or marking ink without written approval, even if it is "equivalent."
• Expect the buyer to ask for the exact product name and lot of every consumable that stays on the part, including thread lockers, potting, conformal coat and marking materials.
• Processes such as heat treat, plating and anodize must be done to the specification named, by a processor the buyer accepts. See surface finishing and heat treatment.

Outgassing and contamination control

Materials that release volatiles in vacuum can redeposit on optics, radiators and solar cells. The standard screening test is ASTM E595: a sample is held at 125 C in vacuum for 24 hours and the total mass loss (TML) and collected volatile condensable material (CVCM) on a collector plate are measured. NASA's outgassing database describes its historical listing as materials meeting a maximum TML of 1.0 percent and a maximum CVCM of 0.10 percent. Where a material fails TML, water vapor regained (WVR) is sometimes used to show that the loss was mostly absorbed water.

Programs with sensitive optics often impose tighter limits or require bakeout of the assembly. A NASA Goddard paper also noted that E595 results ran consistently lower than other measurement methods, so treat E595 as a screen rather than a guarantee.

Practical supplier implications: avoid PVC wire and heat shrink, silicone lubricants and unapproved marking inks; clean machined parts of cutting fluid residue; and package parts so they are not contaminated in storage. Precision cleaning to an IEST-STD-CC1246 level is often called out for parts near optics or in propulsion systems. See precision and oxygen cleaning and engineering plastics for low outgassing polymers.

Environmental verification: GEVS and SMC-S-016

Two documents set most environmental test programs for spacecraft hardware in the United States.

• GSFC-STD-7000, the General Environmental Verification Standard (GEVS). Revision B was approved April 28, 2021 and is listed as active. It provides guidance for environmental verification of Goddard payloads, subsystems and components and a baseline for showing by test or analysis that hardware performs in its mission environments and that workmanship standards have been met. Many NASA and commercial programs reference it.
• SMC-S-016, Test Requirements for Launch, Upper-Stage and Space Vehicles. The 2014 edition is the baseline for many Space Force programs and continues the MIL-STD-1540 lineage. It emphasizes design verification and the detection of latent defects and defines qualification, protoqualification and acceptance strategies. An Aerospace Corporation tailoring report issued in 2020 is used with it on some space vehicle contracts.

A machinist rarely runs vibration or thermal vacuum, but the test campaign still shapes the part. Fastener preload, staking, thread locking and part flatness all show up in a vibration failure. Build the inspection plan around the features that matter in test: interface flatness, hole positions for mounting, thread quality and surface finish on thermal interfaces. See inspection and metrology.

Fracture control and NDE

NASA-STD-5019 sets fracture control requirements for spaceflight hardware. Parts are classified by whether their failure could cause a catastrophic hazard and whether they can be shown safe by low risk rationale, containment or analysis. Parts that are fracture critical need NDE to NASA-STD-5009, which defines NDE requirements where a quantitative probability of detection is required. NASA-STD-5009 excludes in-process NDE used only for process control and NDE of damage tolerant composites.

The practical impact on a supplier is that "penetrant inspect per ASTM E1417" on a drawing may not be enough for a fracture critical part. The buyer may require a special level of penetrant sensitivity, a qualified inspector certified to NAS 410, etched surfaces before penetrant, or a different method. Ask for the fracture classification on every flight structural part. See nondestructive testing.

Electronics and harness workmanship

Space electronics suppliers usually work to IPC J-STD-001 with its space hardware addendum, IPC/WHMA-A-620 with its space addendum for harnesses, and on NASA work the NASA-STD-8739 series, for example NASA-STD-8739.4 for crimping, interconnecting cables, harnesses and wiring. Where the addendum applies it generally takes precedence over the base standard. Revisions change, so cite the revision your contract invokes and confirm operators hold current IPC space addendum certification.

Parts selection is its own discipline. EEE parts on many programs must come from approved sources and meet program derating and screening rules, and counterfeit avoidance under AS5553 applies to electronic parts. If you are buying a populated board or harness, specify who procures the parts and what source restrictions apply.

Small satellites and CubeSats

CubeSat hardware follows the CubeSat Design Specification maintained by Cal Poly. Rev 14.1 requires low outgassing materials (TML at or below 1.0 percent and CVCM at or below 0.1 percent), says rails should have surface roughness below 1.6 micrometers, notes that 7075, 6061, 6082, 5005 and 5052 aluminum are typical for structures and rails, and requires hard anodize on aluminum surfaces that contact the dispenser rails to prevent cold welding. Test levels come from the launch provider. Those requirements are much lighter than a large satellite program, but the hard anodize and rail dimension requirements are frequent sources of rejected structures. More on university CubeSat work is on the research labs and universities page.

Export control

Spacecraft and related articles are USML Category XV. Many commercial satellite items moved to the Commerce Control List under the 9x515 entries during export control reform, but parts specially designed for certain spacecraft remain on the USML. The buyer classifies the item and its data. Drawings for controlled spacecraft hardware should never be sent through a public web form; see controlled programs.

What makes spacecraft parts hard

• Quantity of one, zero rework allowance. Many flight parts cannot be weld repaired, re-anodized or blended without an engineering disposition, so the first part has to be right.
• Thin, pocketed aluminum that moves. Lightweighted panels distort as material is removed. Stress relieved plate, balanced roughing and finish passes after unclamping are the usual answers.
• Hidden consumables. A marking ink, lubricant or tape that is not on the approved list can trigger an MUA or a rejection.
• Records that outlive the program. Expect to deliver material certs, process certs, inspection data and FAI to AS9102, often with AS9145 APQP elements for repeat production.

Request a quote for spacecraft hardware

For machined structures, housings and mechanism details, send the drawing through the quote form under CNC machining with the revision, the M&P document your program uses, fracture classification, finish and cleanliness callouts and any outgassing restrictions. We source from qualified suppliers, flow down your requirements, check the cert package against the purchase order and reply within one business day. See also the industries hub and launch vehicles.

Questions

Related

• Sourcing Launch Vehicle Hardware and Ground Support Equipment
• Sourcing Prototype and Experimental Hardware for Research Labs
• Engineering Plastics for Flight and Ground Hardware
• Nondestructive Testing for Aerospace Parts

Sources

• NASA-STD-6016 (NASA Technical Standards System)
• NASA-STD-6016C, approved September 30, 2021 (PDF)
• NASA Outgassing Database
• CAPLINQ: How outgassing in materials is tested (ASTM E595 conditions)
• NASA GSFC paper comparing ASTM E595 with other outgassing measurements (NTRS)
• CubeSat Design Specification Rev 14.1 (Cal Poly, hosted by NASA)
• GSFC-STD-7000B, General Environmental Verification Standard
• SMC-S-016 (2014), EverySpec listing
• Tailoring of SMC-S-016 (2014), DTIC
• NASA-STD-5009, NDE Requirements for Fracture Critical Metallic Components
• NASA SMA: Updates to NASA-STD-8739.4 crimping, cables, harnesses and wiring
• 22 CFR 121.1, United States Munitions List, Category XV